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All questions of Sample Papers with Solutions for Class 9 Exam
The substance found in the cell wall of cork or bark that makes it impervious to water is- a)cutin
- b)lignin
- c)suberin
- d)lipids
Correct answer is option 'C'. Can you explain this answer?
The substance found in the cell wall of cork or bark that makes it impervious to water is
a)
cutin
b)
lignin
c)
suberin
d)
lipids
|
Aditi Sharma answered |
The cork is impervious to water due to suberin deposition in the cell wall of its cells. The walls of cork cells are heavily thickened with an organic substance, suberin. Suberin makes these cells impervious to water and gases.
A force of 5 N applied on mj produces an acceleration of 8 m/s2 and when applied on m2 produces an acceleration of 24 m/s2. When they are tied together, the acceleration will be- a)3 m/s2
- b)16 m/s2
- c)6 m/s2
- d)8 m/s2
Correct answer is option 'C'. Can you explain this answer?
A force of 5 N applied on mj produces an acceleration of 8 m/s2 and when applied on m2 produces an acceleration of 24 m/s2. When they are tied together, the acceleration will be
a)
3 m/s2
b)
16 m/s2
c)
6 m/s2
d)
8 m/s2
|
Swati Verma answered |
For the first body, F = m1a1
For second body, F = m2a2
Combined mass of both bodies, m1 + m2
For second body, F = m2a2
Combined mass of both bodies, m1 + m2
F = 5N, a = ?
F = ma
So, a = 6m/s2
The outermost layer of the human cheek cell is:- a)Cell wall
- b)Nuclear membrane
- c)Cytoplasm
- d)Plasma membrane
Correct answer is option 'D'. Can you explain this answer?
The outermost layer of the human cheek cell is:
a)
Cell wall
b)
Nuclear membrane
c)
Cytoplasm
d)
Plasma membrane
|
|
Aditi Sharma answered |
The human cheek cell is an animal cell with an outermost membrane as plasma membrane.
Match the following with correct response.
- a)1-C, 2-B, 3-D, 4-A
- b)1-B, 2-D. 3-A, 4-C
- c)1-D, 2-A, 3-C, 4-B
- d)1-A, 2-C, 3-B, 4-D
Correct answer is option 'B'. Can you explain this answer?
Match the following with correct response.
a)
1-C, 2-B, 3-D, 4-A
b)
1-B, 2-D. 3-A, 4-C
c)
1-D, 2-A, 3-C, 4-B
d)
1-A, 2-C, 3-B, 4-D
|
|
Aditi Sharma answered |
1- B In mixtures the components do not lose their properties.
2- D In a compound the constituent elements combine in fixed proportion by mass.
3 - A Elements are made up of same kind of atoms & elements can not be further broken down.
4 - C An atom is the smallest unit of matter that has the properties of an element.
2- D In a compound the constituent elements combine in fixed proportion by mass.
3 - A Elements are made up of same kind of atoms & elements can not be further broken down.
4 - C An atom is the smallest unit of matter that has the properties of an element.
When two substances A and B are powdered together in a pestle and mortar, a large amount of heat is evolved. As a result, a new substance C is formed. What is the nature of the new substance?
i. compound
ii. mixture
iii. element- a)Mixture
- b)Compound
- c)Element
- d)Both compound and mixture
Correct answer is option 'B'. Can you explain this answer?
When two substances A and B are powdered together in a pestle and mortar, a large amount of heat is evolved. As a result, a new substance C is formed. What is the nature of the new substance?
i. compound
ii. mixture
iii. element
i. compound
ii. mixture
iii. element
a)
Mixture
b)
Compound
c)
Element
d)
Both compound and mixture
|
Pratibha Patel answered |
Answer:
When two substances A and B are powdered together in a pestle and mortar, and a large amount of heat is evolved, it indicates a chemical reaction taking place. This reaction results in the formation of a new substance C. The nature of the new substance C can be determined by considering the properties and characteristics of mixtures, compounds, and elements.
Mixture:
A mixture is a combination of two or more substances that are physically mixed together and can be separated by physical means. In a mixture, the substances retain their individual properties and do not undergo any chemical change. However, in the given scenario, when substances A and B are powdered together, a chemical reaction occurs, indicating that a mixture is not formed.
Element:
An element is a pure substance that cannot be broken down into simpler substances by chemical means. Elements are made up of only one type of atom. In the given scenario, the fact that two substances A and B are combining and reacting with each other suggests that the new substance C is not an element.
Compound:
A compound is a pure substance composed of two or more elements that are chemically combined in a fixed ratio. Compounds have properties different from the elements that make them up, and they can only be separated into their constituent elements by chemical means. When substances A and B are powdered together, and a chemical reaction occurs, resulting in the formation of a new substance C, it indicates the formation of a compound. Therefore, the nature of the new substance C is a compound.
Conclusion:
Based on the given information, when substances A and B are powdered together in a pestle and mortar, and a large amount of heat is evolved, a new substance C is formed. The nature of the new substance C is a compound.
When two substances A and B are powdered together in a pestle and mortar, and a large amount of heat is evolved, it indicates a chemical reaction taking place. This reaction results in the formation of a new substance C. The nature of the new substance C can be determined by considering the properties and characteristics of mixtures, compounds, and elements.
Mixture:
A mixture is a combination of two or more substances that are physically mixed together and can be separated by physical means. In a mixture, the substances retain their individual properties and do not undergo any chemical change. However, in the given scenario, when substances A and B are powdered together, a chemical reaction occurs, indicating that a mixture is not formed.
Element:
An element is a pure substance that cannot be broken down into simpler substances by chemical means. Elements are made up of only one type of atom. In the given scenario, the fact that two substances A and B are combining and reacting with each other suggests that the new substance C is not an element.
Compound:
A compound is a pure substance composed of two or more elements that are chemically combined in a fixed ratio. Compounds have properties different from the elements that make them up, and they can only be separated into their constituent elements by chemical means. When substances A and B are powdered together, and a chemical reaction occurs, resulting in the formation of a new substance C, it indicates the formation of a compound. Therefore, the nature of the new substance C is a compound.
Conclusion:
Based on the given information, when substances A and B are powdered together in a pestle and mortar, and a large amount of heat is evolved, a new substance C is formed. The nature of the new substance C is a compound.
Read the text carefully and answer the questions:
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
Q. Which of the following is an example of solid sol?- a)Shaving cream
- b)Fog
- c)Coloured gemstone
- d)Milk
Correct answer is option 'C'. Can you explain this answer?
Read the text carefully and answer the questions:
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
Q. Which of the following is an example of solid sol?
a)
Shaving cream
b)
Fog
c)
Coloured gemstone
d)
Milk
|
Ascendry Ok answered |
Gemstone is solid and the question asked what is a *solid* sol
Assertion (A): Plasma membrane is selectively permeable.
Reason (R): Plasma membrane allows some molecules to pass through it more easily than others.- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true but R is not the correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'A'. Can you explain this answer?
Assertion (A): Plasma membrane is selectively permeable.
Reason (R): Plasma membrane allows some molecules to pass through it more easily than others.
Reason (R): Plasma membrane allows some molecules to pass through it more easily than others.
a)
Both A and R are true and R is the correct explanation of A.
b)
Both A and R are true but R is not the correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
Nandini Ahuja answered |
Assertion (A): Plasma membrane is selectively permeable.
Reason (R): Plasma membrane allows some molecules to pass through it more easily than others.
The correct answer is option 'A', i.e., Both A and R are true and R is the correct explanation of A.
Explanation:
The plasma membrane is a crucial component of all living cells. It encloses the cell's contents and acts as a barrier between the cell and its external environment. The selective permeability of the plasma membrane allows certain substances to pass through it more easily than others.
Plasma Membrane:
The plasma membrane is made up of a phospholipid bilayer with embedded proteins. The phospholipids have a hydrophilic head and hydrophobic tails. These phospholipids arrange themselves in a bilayer with the hydrophilic heads facing outward towards the aqueous environment and the hydrophobic tails facing inward, away from the water.
Function of Plasma Membrane:
The primary function of the plasma membrane is to regulate the movement of substances into and out of the cell. It is selectively permeable, meaning it allows certain molecules or ions to pass through while preventing others from crossing.
Selective Permeability:
The selective permeability of the plasma membrane is due to its structure and the presence of various proteins. The phospholipid bilayer acts as a barrier to the movement of polar and charged molecules, as they cannot easily pass through the hydrophobic interior. However, small non-polar molecules, such as oxygen and carbon dioxide, can pass through the plasma membrane easily through simple diffusion.
Mechanisms of Transport:
The plasma membrane employs different mechanisms to transport substances across it, including passive transport (simple diffusion, facilitated diffusion, and osmosis) and active transport (protein-mediated transport using energy).
Explanation of Assertion and Reason:
Assertion (A) states that the plasma membrane is selectively permeable, which means it allows some molecules to pass through more easily than others. This is supported by the fact that the phospholipid bilayer of the plasma membrane acts as a barrier to polar and charged molecules but allows the passage of small non-polar molecules.
Reason (R) correctly explains Assertion (A) by stating that the plasma membrane allows some molecules to pass through more easily than others. The selective permeability of the plasma membrane is essential for maintaining homeostasis within the cell and regulating the movement of substances in and out of the cell.
Therefore, both Assertion (A) and Reason (R) are true, and Reason (R) provides the correct explanation for Assertion (A).
Reason (R): Plasma membrane allows some molecules to pass through it more easily than others.
The correct answer is option 'A', i.e., Both A and R are true and R is the correct explanation of A.
Explanation:
The plasma membrane is a crucial component of all living cells. It encloses the cell's contents and acts as a barrier between the cell and its external environment. The selective permeability of the plasma membrane allows certain substances to pass through it more easily than others.
Plasma Membrane:
The plasma membrane is made up of a phospholipid bilayer with embedded proteins. The phospholipids have a hydrophilic head and hydrophobic tails. These phospholipids arrange themselves in a bilayer with the hydrophilic heads facing outward towards the aqueous environment and the hydrophobic tails facing inward, away from the water.
Function of Plasma Membrane:
The primary function of the plasma membrane is to regulate the movement of substances into and out of the cell. It is selectively permeable, meaning it allows certain molecules or ions to pass through while preventing others from crossing.
Selective Permeability:
The selective permeability of the plasma membrane is due to its structure and the presence of various proteins. The phospholipid bilayer acts as a barrier to the movement of polar and charged molecules, as they cannot easily pass through the hydrophobic interior. However, small non-polar molecules, such as oxygen and carbon dioxide, can pass through the plasma membrane easily through simple diffusion.
Mechanisms of Transport:
The plasma membrane employs different mechanisms to transport substances across it, including passive transport (simple diffusion, facilitated diffusion, and osmosis) and active transport (protein-mediated transport using energy).
Explanation of Assertion and Reason:
Assertion (A) states that the plasma membrane is selectively permeable, which means it allows some molecules to pass through more easily than others. This is supported by the fact that the phospholipid bilayer of the plasma membrane acts as a barrier to polar and charged molecules but allows the passage of small non-polar molecules.
Reason (R) correctly explains Assertion (A) by stating that the plasma membrane allows some molecules to pass through more easily than others. The selective permeability of the plasma membrane is essential for maintaining homeostasis within the cell and regulating the movement of substances in and out of the cell.
Therefore, both Assertion (A) and Reason (R) are true, and Reason (R) provides the correct explanation for Assertion (A).
Intercalated disc is present in _____.- a)Both Smooth muscle and Cardiac muscle
- b)Striated muscle
- c)Smooth muscle
- d)Cardiac muscle
Correct answer is option 'D'. Can you explain this answer?
Intercalated disc is present in _____.
a)
Both Smooth muscle and Cardiac muscle
b)
Striated muscle
c)
Smooth muscle
d)
Cardiac muscle
|
|
Swati Verma answered |
The heart of human beings is made up of cardiac muscles which are different from smooth and skeletal muscles. Inside the cardiac muscles are the intercalated discs which are known to join various adjacent cells together. There are a number of functions of intercalated discs. It is only when it functions properly that the heart can work effectively.
Internal forces are forces which bodies exert on each other when the bodies are part of the system is- a)false
- b)partially false
- c)partially true
- d)true
Correct answer is option 'D'. Can you explain this answer?
Internal forces are forces which bodies exert on each other when the bodies are part of the system is
a)
false
b)
partially false
c)
partially true
d)
true
|
Lavanya Menon answered |
Internal forces are those forces which are exerted on each other when the bodies are part of the system. The forces acting between the atoms of molecules that keep them together are an example of internal force.
Select the incorrect sentence- a)Cartilage is a form of connective tissue
- b)Tendons are non-fibrous tissue and fragile
- c)Two bones are connected with ligament
- d)Blood has matrix containing proteins, salts, and hormones
Correct answer is option 'B'. Can you explain this answer?
Select the incorrect sentence
a)
Cartilage is a form of connective tissue
b)
Tendons are non-fibrous tissue and fragile
c)
Two bones are connected with ligament
d)
Blood has matrix containing proteins, salts, and hormones
|
|
Aditi Sharma answered |
Tendons are white fibrous connective tissues having great strength and join skeletal muscles with bones.
If two objects move in a circular path of radii in the ratio of 1:3 and take some time to complete the circle, what is the ratio of their speeds?- a)1:3
- b)3:1
- c)r2/r1
- d)r1/r2
Correct answer is option 'A'. Can you explain this answer?
If two objects move in a circular path of radii in the ratio of 1:3 and take some time to complete the circle, what is the ratio of their speeds?
a)
1:3
b)
3:1
c)
r2/r1
d)
r1/r2
|
Fatima Sheikh answered |
Explanation:
- Given:
- Radii of the circular paths in the ratio of 1:3
- Time taken to complete the circle is the same for both objects
- Speed and Radius Relationship:
- The speed of an object moving in a circular path is directly proportional to the radius of the circle.
- Mathematically, speed ∝ radius
- Ratio of Speeds:
- Let the radii of the circles be r1 and r2, such that r2 = 3r1 (given ratio is 1:3)
- Let the speeds of the objects be v1 and v2
- From the speed-radius relationship, we have v1 ∝ r1 and v2 ∝ r2
- Therefore, v1/v2 = r1/r2
- Substituting r2 = 3r1, we get v1/v2 = r1/3r1 = 1/3
- So, the ratio of speeds of the two objects is 1:3
Therefore, the correct answer is option 'A' - 1:3.
- Given:
- Radii of the circular paths in the ratio of 1:3
- Time taken to complete the circle is the same for both objects
- Speed and Radius Relationship:
- The speed of an object moving in a circular path is directly proportional to the radius of the circle.
- Mathematically, speed ∝ radius
- Ratio of Speeds:
- Let the radii of the circles be r1 and r2, such that r2 = 3r1 (given ratio is 1:3)
- Let the speeds of the objects be v1 and v2
- From the speed-radius relationship, we have v1 ∝ r1 and v2 ∝ r2
- Therefore, v1/v2 = r1/r2
- Substituting r2 = 3r1, we get v1/v2 = r1/3r1 = 1/3
- So, the ratio of speeds of the two objects is 1:3
Therefore, the correct answer is option 'A' - 1:3.
Which will not give a stable solution even when stirred for sometimes?- a)Milk in water
- b)Common salt in water
- c)Egg albumin in water
- d)Sugar in water
Correct answer is option 'C'. Can you explain this answer?
Which will not give a stable solution even when stirred for sometimes?
a)
Milk in water
b)
Common salt in water
c)
Egg albumin in water
d)
Sugar in water
|
|
Swati Verma answered |
Egg albumin in water will not give a stable solution. The protein in egg albumin coagulated to form a lump in hot water.
To observe starch granules in potato under a microscope, freshly cut surface of potato placed on a slide. The stain that will show starch granules clearly is:- a)safranin
- b)iodine
- c)eosin
- d)methylene blue
Correct answer is option 'B'. Can you explain this answer?
To observe starch granules in potato under a microscope, freshly cut surface of potato placed on a slide. The stain that will show starch granules clearly is:
a)
safranin
b)
iodine
c)
eosin
d)
methylene blue
|
Hansa Sharma answered |
Place a slice of a potato on a paper towel at top of a paper plate and add a drop of the iodine solution to the potato slice. Note the color change. A change of color to blue-black or purple color suggests that starch is present. If there is no change in color, this suggests no starch is detectable.
70-80% of the volume of a mature plant cell is occupied by:- a)cytoplasm
- b)vacuole
- c)nucleus
- d)endoplasmic reticulum
Correct answer is option 'B'. Can you explain this answer?
70-80% of the volume of a mature plant cell is occupied by:
a)
cytoplasm
b)
vacuole
c)
nucleus
d)
endoplasmic reticulum
|
|
Aditi Sharma answered |
Vacuoles occupy a very large part of the cell volume in plants. Upton 95% of cellular volume can be occupied by them.
Assertion (A): When the displacement of a body is directly proportional to the square of the time. Then the body is moving with uniform acceleration.
Reason (R): The slope of velocity-time graph with time axis gives acceleration.- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true but R is not the correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'B'. Can you explain this answer?
Assertion (A): When the displacement of a body is directly proportional to the square of the time. Then the body is moving with uniform acceleration.
Reason (R): The slope of velocity-time graph with time axis gives acceleration.
Reason (R): The slope of velocity-time graph with time axis gives acceleration.
a)
Both A and R are true and R is the correct explanation of A.
b)
Both A and R are true but R is not the correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
|
Avinash Patel answered |
Explanation:
Assertion (A): When the displacement of a body is directly proportional to the square of the time. Then the body is moving with uniform acceleration.
Reason (R): The slope of velocity-time graph with time axis gives acceleration.
Conclusion:
Both A and R are true but R is not the correct explanation of A.
To determine the correctness of the assertion and the reason, let's analyze each statement separately:
Assertion (A): When the displacement of a body is directly proportional to the square of the time. Then the body is moving with uniform acceleration.
This statement implies that the displacement-time relationship is given by:
s ∝ t^2
If displacement is directly proportional to the square of time, it means that the body is undergoing uniform acceleration. This is because the equation of motion for an object moving with uniform acceleration is given by:
s = ut + (1/2)at^2
Since the displacement is directly proportional to the square of time, the coefficient of t^2 is (1/2)a, which means the acceleration is constant. Therefore, assertion (A) is true.
Reason (R): The slope of velocity-time graph with time axis gives acceleration.
The slope of a velocity-time graph represents the rate of change of velocity with respect to time, which is acceleration. This is derived from the definition of acceleration as the rate of change of velocity:
a = Δv / Δt
The slope of the velocity-time graph is given by:
slope = (change in velocity) / (change in time)
Therefore, the reason (R) is true.
Conclusion:
From the analysis of both the assertion and the reason, we can conclude that:
Both A and R are true but R is not the correct explanation of A.
The reason (R) is true and provides additional evidence for the validity of the assertion (A), but it does not directly explain why the body is moving with uniform acceleration when the displacement is proportional to the square of time.
Read the text carefully and answer the questions:
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Q. The cell organelle involved in forming complex sugars from simple sugars are:- a)golgi apparatus
- b)ribosomes
- c)endoplasmic reticulum
- d)plastids
Correct answer is option 'A'. Can you explain this answer?
Read the text carefully and answer the questions:
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Q. The cell organelle involved in forming complex sugars from simple sugars are:
a)
golgi apparatus
b)
ribosomes
c)
endoplasmic reticulum
d)
plastids
|
lavi kasana answered |
Golgi appartus is correct answer
The organelle which is absent in kidney cells is:- a)Centrioles
- b)Chloroplast
- c)Plasma membrane
- d)Mitochondria
Correct answer is option 'B'. Can you explain this answer?
The organelle which is absent in kidney cells is:
a)
Centrioles
b)
Chloroplast
c)
Plasma membrane
d)
Mitochondria
|
Geetika Shah answered |
Since kidney is a part of an animal cell so chloroplast is absent.
Take three test tubes A, B and C containing salt solution, egg albumin in water and suspension of sand in water. Filter the contents of A, B, C through filter paper and observe the residue and filtrate. Identify the correct statements.- a)Residue left and clear filtrate in all
- b)No residue and clear filtrate in all the test tubes
- c)Translucent filtrate in all
- d)A clear filtrate and no residue in A, translucent filtrate and no residue in B, solid particles as residue and clear filtrate in C
Correct answer is option 'D'. Can you explain this answer?
Take three test tubes A, B and C containing salt solution, egg albumin in water and suspension of sand in water. Filter the contents of A, B, C through filter paper and observe the residue and filtrate. Identify the correct statements.
a)
Residue left and clear filtrate in all
b)
No residue and clear filtrate in all the test tubes
c)
Translucent filtrate in all
d)
A clear filtrate and no residue in A, translucent filtrate and no residue in B, solid particles as residue and clear filtrate in C
|
|
Aditi Sharma answered |
A clear filtrate and no residue in A, translucent filtrate and no residue in B, solid particles as residue and clear filtrate in C.
Read the text carefully and answer the questions:
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Q. Which of the given are covered by a single membrane?- a)Plastid
- b)Lysosome
- c)Vacuole
- d)Mitochondria
Correct answer is option 'C'. Can you explain this answer?
Read the text carefully and answer the questions:
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Q. Which of the given are covered by a single membrane?
a)
Plastid
b)
Lysosome
c)
Vacuole
d)
Mitochondria
|
|
Swati Verma answered |
A lysosome is covered by a single membrane. Lysosomes are an essential cell organelle present inside the eukaryotic animal cells. Due to their function, they are also called as the “suicide bags” of the cell. Lysosomes are single membrane-bound organelles and the region inside the membrane is known as the lumen, which includes the hydrolytic enzymes and other cellular debris. The vital role of lysosomes is digestion and removal of waste. Cellular debris or foreign particles are pulled into the cell by the process of endocytosis. The process of endocytosis takes place when the cell membrane falls in on itself (invagination), creating a vacuole or a pouch near the external contents and then bringing those contents into the cell.
Vacuole is also a single membrane structure or organelle found in the cytoplasm with varying sizes. Whereas mitochondria given in the option is double membrane bound organelle.
Match the following with correct response:
- a)1-B, 2-D, 3-A, 4-C
- b)1-D, 2-A, 3-C, 4-B
- c)1-C, 2-B, 3-D, 4-A
- d)1-A, 2-C, 3-B, 4-D
Correct answer is option 'A'. Can you explain this answer?
Match the following with correct response:
a)
1-B, 2-D, 3-A, 4-C
b)
1-D, 2-A, 3-C, 4-B
c)
1-C, 2-B, 3-D, 4-A
d)
1-A, 2-C, 3-B, 4-D
|
Imk Pathshala answered |
Cells are enclosed by a plasma membrane composed of proteins and lipids. It separates the contents of the cell from the external environment. It permits entry of selective substances in the cell. It allows exit of selective substances from the cell.
Tonoplast is the membrane which bounds the chief vacuole of a plant cell. It is also known as the vacuolar membrane. It separates the vacuolar contents from the cytoplasm of the cell.
Stroma is the ground material of chloroplast. It is the part of a tissue or an organ that has a connective and structural role.
Each of the partial partitions in a mitochondrion formed by infolding of the inner membrane is known as Cristae.
Tonoplast is the membrane which bounds the chief vacuole of a plant cell. It is also known as the vacuolar membrane. It separates the vacuolar contents from the cytoplasm of the cell.
Stroma is the ground material of chloroplast. It is the part of a tissue or an organ that has a connective and structural role.
Each of the partial partitions in a mitochondrion formed by infolding of the inner membrane is known as Cristae.
Which of the following is an example of uniform motion?
A. The motion of the car in a busy road
B. The motion of a satellite around the planet
C. The motion of the moon around the earth
D. The motion of any particle on the arm of a clock.- a)A, B and D
- b)A, C and D
- c)All of these
- d)B, C, and D
Correct answer is option 'D'. Can you explain this answer?
Which of the following is an example of uniform motion?
A. The motion of the car in a busy road
B. The motion of a satellite around the planet
C. The motion of the moon around the earth
D. The motion of any particle on the arm of a clock.
A. The motion of the car in a busy road
B. The motion of a satellite around the planet
C. The motion of the moon around the earth
D. The motion of any particle on the arm of a clock.
a)
A, B and D
b)
A, C and D
c)
All of these
d)
B, C, and D
|
|
Geetika Shah answered |
Uniform motion is the kind of motion in which a body covers equal distances in equal intervals of time.
For example B, C, and D, the bodies cover equal distances in equal intervals of time.
For example B, C, and D, the bodies cover equal distances in equal intervals of time.
A mixture of iron filings and sulphur is heated in a hard boiling tube. Which of the following will be observed?- a)Iron will melt first
- b)Sulphur will melt first
- c)The mixture becomes red hot without melting
- d)Mixture sublimes
Correct answer is option 'B'. Can you explain this answer?
A mixture of iron filings and sulphur is heated in a hard boiling tube. Which of the following will be observed?
a)
Iron will melt first
b)
Sulphur will melt first
c)
The mixture becomes red hot without melting
d)
Mixture sublimes
|
|
Aditi Sharma answered |
When we start heating a mixture of iron filing and sulphur, the sulphur melts reacting exothermically (that is with the production of heat) with the iron filings to form the compound Iron (II) sulfide. The compound formed has properties that are different from both sulfur and iron. For instance, the compound does not have the magnetic properties of iron, and thus a magnet that could have easily separated iron nails and sulphur initially, will not be able to separate iron and sulphur from Iron (II) sulphide.
Assertion (A): Cell vomiting process occurs in cells to remove undigested substances, secrete hormones, enzymes, and transport various substances.
Reason (R): Cell vomiting is a process in which the waste materials from the cell are extruded through the plasma membrane by diffusing the vesicles containing materials needs to be taken out of the body.- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true but R is not the correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'A'. Can you explain this answer?
Assertion (A): Cell vomiting process occurs in cells to remove undigested substances, secrete hormones, enzymes, and transport various substances.
Reason (R): Cell vomiting is a process in which the waste materials from the cell are extruded through the plasma membrane by diffusing the vesicles containing materials needs to be taken out of the body.
Reason (R): Cell vomiting is a process in which the waste materials from the cell are extruded through the plasma membrane by diffusing the vesicles containing materials needs to be taken out of the body.
a)
Both A and R are true and R is the correct explanation of A.
b)
Both A and R are true but R is not the correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
Meera Rana answered |
Exocytosis or cell vomiting is a process in which the waste materials from the cell are extruded through the plasma membrane by diffusing the vesicles containing materials that need to be taken out of the body. This process occurs in cells to remove undigested substances, secrete hormones, enzymes, and transport various substances.
Read the text carefully and answer the questions:
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Q. Which cell organelle plays a crucial role in detoxifying many poisons and drugs in a cell?- a)Vacuoles
- b)Golgi apparatus
- c)Lysosomes
- d)Smooth endoplasmic reticulum
Correct answer is option 'D'. Can you explain this answer?
Read the text carefully and answer the questions:
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Cell organelles are enclosed by membranes. Cell organelles are the endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and plastids. The endoplasmic reticulum (ER) is a large network of membrane-bound tubes and sheets. It looks like long tubules or round or oblong bags. There are two types of ER rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER looks rough under a microscope because it has particles called ribosomes attached to its surface. The ribosomes, which are present in all active cells, are the sites of protein manufacture. The Golgi apparatus, first described by Camillo Golgi, consists of a system of membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
Q. Which cell organelle plays a crucial role in detoxifying many poisons and drugs in a cell?
a)
Vacuoles
b)
Golgi apparatus
c)
Lysosomes
d)
Smooth endoplasmic reticulum
|
Divya Sriram answered |
The Smooth Endoplasmic Reticulum (SER) plays a crucial role in detoxifying many poisons and drugs in the liver cells of vertebrates. So option D is correct.
Newton's First Law of Motion is also called as:-- a)Law of Action & Reaction
- b)Law of Momentum
- c)None of these
- d)Law of Inertia
Correct answer is option 'D'. Can you explain this answer?
Newton's First Law of Motion is also called as:-
a)
Law of Action & Reaction
b)
Law of Momentum
c)
None of these
d)
Law of Inertia
|
|
Swati Verma answered |
Newton's first law of motion is also referred to as the Law of Inertia. An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Complex tissue consists of:- a)Different types of cells carrying out the different function
- b)Different types of cells carrying out the same function
- c)Same types of cells having the same origin and carry the same function
- d)Different types of cells having the same origin and carry the same function.
Correct answer is option 'B'. Can you explain this answer?
Complex tissue consists of:
a)
Different types of cells carrying out the different function
b)
Different types of cells carrying out the same function
c)
Same types of cells having the same origin and carry the same function
d)
Different types of cells having the same origin and carry the same function.
|
Gayatri Sengupta answered |
Understanding Complex Tissue
Complex tissues are an essential part of plant structure, made up of various cell types that work together for specific functions.
Definition of Complex Tissue
- Complex tissue refers to a group of different types of cells that function collaboratively.
- It is typically found in plants and plays vital roles in growth, support, and transport of nutrients and water.
Option Analysis
- Option A: Different types of cells carrying out different functions
- This is incorrect because complex tissues are characterized by cells that work together towards a common function.
- Option B: Different types of cells carrying out the same function
- This is the correct answer. In complex tissues, various cell types cooperate to fulfill a unified purpose, such as in xylem or phloem, where different cells work together to transport water and nutrients.
- Option C: Same types of cells having the same origin and carry the same function
- This describes simple tissues, not complex tissues, as complex tissues consist of diverse cell types.
- Option D: Different types of cells having the same origin and carry the same function
- This is misleading; while the cells may have a common origin, they do not necessarily perform the same function, which is a defining trait of complex tissues.
Examples of Complex Tissue
- Xylem: Transports water and minerals from roots to leaves, composed of vessels, tracheids, fibers, and parenchyma.
- Phloem: Responsible for transporting nutrients, primarily sugars, composed of sieve tubes, companion cells, fibers, and parenchyma.
Conclusion
- Complex tissues are crucial for plant functioning, showcasing the collaboration of different cell types to achieve specific tasks efficiently. This intricate organization allows plants to thrive in diverse environments.
Complex tissues are an essential part of plant structure, made up of various cell types that work together for specific functions.
Definition of Complex Tissue
- Complex tissue refers to a group of different types of cells that function collaboratively.
- It is typically found in plants and plays vital roles in growth, support, and transport of nutrients and water.
Option Analysis
- Option A: Different types of cells carrying out different functions
- This is incorrect because complex tissues are characterized by cells that work together towards a common function.
- Option B: Different types of cells carrying out the same function
- This is the correct answer. In complex tissues, various cell types cooperate to fulfill a unified purpose, such as in xylem or phloem, where different cells work together to transport water and nutrients.
- Option C: Same types of cells having the same origin and carry the same function
- This describes simple tissues, not complex tissues, as complex tissues consist of diverse cell types.
- Option D: Different types of cells having the same origin and carry the same function
- This is misleading; while the cells may have a common origin, they do not necessarily perform the same function, which is a defining trait of complex tissues.
Examples of Complex Tissue
- Xylem: Transports water and minerals from roots to leaves, composed of vessels, tracheids, fibers, and parenchyma.
- Phloem: Responsible for transporting nutrients, primarily sugars, composed of sieve tubes, companion cells, fibers, and parenchyma.
Conclusion
- Complex tissues are crucial for plant functioning, showcasing the collaboration of different cell types to achieve specific tasks efficiently. This intricate organization allows plants to thrive in diverse environments.
The extra stain from the slide if present is removed by:- a)keeping slide under running water
- b)evaporation by heating
- c)soaking with filter paper
- d)drying stain under sunlight
Correct answer is option 'C'. Can you explain this answer?
The extra stain from the slide if present is removed by:
a)
keeping slide under running water
b)
evaporation by heating
c)
soaking with filter paper
d)
drying stain under sunlight
|
|
Bhargavi Saha answered |
Explanation:
When a slide is stained for microscopic examination, sometimes there may be an extra stain left behind on the slide. This extra stain can interfere with the observation and interpretation of the slide. To remove this extra stain, the slide can be soaked with filter paper.
Soaking with Filter Paper:
Soaking the slide with filter paper is an effective method to remove the extra stain. This process involves placing a piece of filter paper on the stained area of the slide and allowing it to absorb the excess stain. The filter paper acts as a wick, drawing the stain away from the slide surface.
Steps to remove the extra stain:
1. Take a clean filter paper and cut it into small pieces.
2. Place one piece of filter paper on the stained area of the slide.
3. Gently press the filter paper against the stain, allowing it to absorb the excess stain.
4. Remove the filter paper and examine the slide to see if the extra stain has been removed.
5. If necessary, repeat the process with a fresh piece of filter paper until the stain is completely removed.
Reasoning:
The extra stain is removed by soaking the slide with filter paper because the filter paper has a high absorbency. It can effectively absorb liquids, including stains, due to its porous nature. When the filter paper comes into contact with the extra stain, capillary action takes place, causing the stain to be drawn into the pores of the filter paper. This helps in removing the excess stain from the slide, leaving behind a clean surface for observation.
Soaking with filter paper is preferred over other options mentioned in the question because:
- Running water (option A) may not be sufficient to remove the extra stain completely, and it can also wash away the desired stain.
- Evaporation by heating (option B) may not be suitable as some stains can be heat-sensitive and may lose their color or structure when exposed to high temperatures.
- Drying the stain under sunlight (option D) may not be effective as sunlight alone may not have enough drying power to remove the stain.
In conclusion, soaking the slide with filter paper is the most appropriate method to remove the extra stain, ensuring a clear and accurate microscopic observation.
When a slide is stained for microscopic examination, sometimes there may be an extra stain left behind on the slide. This extra stain can interfere with the observation and interpretation of the slide. To remove this extra stain, the slide can be soaked with filter paper.
Soaking with Filter Paper:
Soaking the slide with filter paper is an effective method to remove the extra stain. This process involves placing a piece of filter paper on the stained area of the slide and allowing it to absorb the excess stain. The filter paper acts as a wick, drawing the stain away from the slide surface.
Steps to remove the extra stain:
1. Take a clean filter paper and cut it into small pieces.
2. Place one piece of filter paper on the stained area of the slide.
3. Gently press the filter paper against the stain, allowing it to absorb the excess stain.
4. Remove the filter paper and examine the slide to see if the extra stain has been removed.
5. If necessary, repeat the process with a fresh piece of filter paper until the stain is completely removed.
Reasoning:
The extra stain is removed by soaking the slide with filter paper because the filter paper has a high absorbency. It can effectively absorb liquids, including stains, due to its porous nature. When the filter paper comes into contact with the extra stain, capillary action takes place, causing the stain to be drawn into the pores of the filter paper. This helps in removing the excess stain from the slide, leaving behind a clean surface for observation.
Soaking with filter paper is preferred over other options mentioned in the question because:
- Running water (option A) may not be sufficient to remove the extra stain completely, and it can also wash away the desired stain.
- Evaporation by heating (option B) may not be suitable as some stains can be heat-sensitive and may lose their color or structure when exposed to high temperatures.
- Drying the stain under sunlight (option D) may not be effective as sunlight alone may not have enough drying power to remove the stain.
In conclusion, soaking the slide with filter paper is the most appropriate method to remove the extra stain, ensuring a clear and accurate microscopic observation.
Assertion (A): Most of plant tissues are dead.
Reason (R): Due to the sedentary existence of plants, dead cells provide mechanical strength more easily than live ones and need less maintenance.- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true but R is not the correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'A'. Can you explain this answer?
Assertion (A): Most of plant tissues are dead.
Reason (R): Due to the sedentary existence of plants, dead cells provide mechanical strength more easily than live ones and need less maintenance.
Reason (R): Due to the sedentary existence of plants, dead cells provide mechanical strength more easily than live ones and need less maintenance.
a)
Both A and R are true and R is the correct explanation of A.
b)
Both A and R are true but R is not the correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
Ashish Menon answered |
Assertion (A): Most of plant tissues are dead.
Plant tissues can be classified into two main types: living tissues and dead tissues. A significant portion of plant tissues, particularly in the context of structural support, consists of dead cells. Examples include:
- **Sclerenchyma:** This tissue provides strength and support. It is composed of dead cells with thickened walls, making it ideal for structural integrity.
- **Xylem:** Responsible for water transport, xylem vessels are formed from dead cells that create a hollow tube, allowing for efficient movement of water and nutrients.
Reason (R): Due to the sedentary existence of plants, dead cells provide mechanical strength more easily than live ones and need less maintenance.
The sedentary lifestyle of plants means they remain fixed in one location. As a result, they require tissues that provide stability and support. Dead cells fulfill this role effectively:
- **Mechanical Strength:** Dead cells, like those in sclerenchyma and xylem, have rigid structures that offer stronger support than living cells, which are often more flexible and can be prone to damage.
- **Less Maintenance:** Dead tissues do not require metabolic energy for maintenance, making them ideal for a plant's energy conservation.
Conclusion:
- **Both A and R are true and R is the correct explanation of A.**
- The assertion is accurate as a large proportion of plant tissues are indeed dead, primarily for structural purposes. The reason effectively explains why dead tissues are advantageous for plants, due to their need for mechanical strength and lower maintenance.
Thus, the correct answer is option 'A'.
Plant tissues can be classified into two main types: living tissues and dead tissues. A significant portion of plant tissues, particularly in the context of structural support, consists of dead cells. Examples include:
- **Sclerenchyma:** This tissue provides strength and support. It is composed of dead cells with thickened walls, making it ideal for structural integrity.
- **Xylem:** Responsible for water transport, xylem vessels are formed from dead cells that create a hollow tube, allowing for efficient movement of water and nutrients.
Reason (R): Due to the sedentary existence of plants, dead cells provide mechanical strength more easily than live ones and need less maintenance.
The sedentary lifestyle of plants means they remain fixed in one location. As a result, they require tissues that provide stability and support. Dead cells fulfill this role effectively:
- **Mechanical Strength:** Dead cells, like those in sclerenchyma and xylem, have rigid structures that offer stronger support than living cells, which are often more flexible and can be prone to damage.
- **Less Maintenance:** Dead tissues do not require metabolic energy for maintenance, making them ideal for a plant's energy conservation.
Conclusion:
- **Both A and R are true and R is the correct explanation of A.**
- The assertion is accurate as a large proportion of plant tissues are indeed dead, primarily for structural purposes. The reason effectively explains why dead tissues are advantageous for plants, due to their need for mechanical strength and lower maintenance.
Thus, the correct answer is option 'A'.
Match the following with the correct response:
- a)(a) - (i), (b) - (iii), (c) - (ii), (d) - (iv)
- b)(a) - (iv), (b) - (i), (c) - (iii), (d) - (ii)
- c)(a) - (iii), (b) - (ii), (c) - (iv), (d) - (i)
- d)(a) - (ii), (b) - (iv), (c) - (i), (d) - (iii)
Correct answer is option 'B'. Can you explain this answer?
Match the following with the correct response:
a)
(a) - (i), (b) - (iii), (c) - (ii), (d) - (iv)
b)
(a) - (iv), (b) - (i), (c) - (iii), (d) - (ii)
c)
(a) - (iii), (b) - (ii), (c) - (iv), (d) - (i)
d)
(a) - (ii), (b) - (iv), (c) - (i), (d) - (iii)
|
|
Aditi Sharma answered |
- In a prokaryotic cell, the nuclear region is poorly defined due to the absence of a nuclear membrane. Such an undefined nuclear region containing only nucleic acids is called a nucleoid,
- On the other hand, organisms with cells having a nuclear membrane are called eukaryotes. Eukaryotic cells are considered complete cells.
- Viruses are the link between the living and the non-living because they lack membranes and do not show any characteristics of life until they enter the body of a host,
- Peroxisomes are small, membrane-enclosed organelles that contain enzymes involved in a variety of metabolic reactions. They help in the removal of toxic substances from the cell. They are surrounded by only a single membrane.
Which of the following components are seen in a slide of human cheek cell when observed under a microscope?- a)Cell wall, cytoplasm, nucleus
- b)Cell membrane, protoplasm, nucleus
- c)Cell membrane, cytoplasm, nucleus
- d)Cell wall, protoplasm, nucleus
Correct answer is option 'C'. Can you explain this answer?
Which of the following components are seen in a slide of human cheek cell when observed under a microscope?
a)
Cell wall, cytoplasm, nucleus
b)
Cell membrane, protoplasm, nucleus
c)
Cell membrane, cytoplasm, nucleus
d)
Cell wall, protoplasm, nucleus
|
|
Swati Verma answered |
The cells do not have a cell wall. However, each cell has a thin cell membrane. A large vacuole is present at the center of each cell and is surrounded by the cytoplasm. A lightly stained cytoplasm is observed in each cell. A deeply stained nucleus is observed at the center of each cell.
The cell walls of collenehyma tissues are unevenly thickened due to- a)Both cellulose and pectin
- b)Pectin
- c)Lignin
- d)Cellulose
Correct answer is option 'A'. Can you explain this answer?
The cell walls of collenehyma tissues are unevenly thickened due to
a)
Both cellulose and pectin
b)
Pectin
c)
Lignin
d)
Cellulose
|
|
Swati Verma answered |
The collenchyma is the typical supporting tissue of the primary plant body and growing plant parts, though it is kept with unaltered structure and function even in outgrown organs like stems, petioles, laminae or roots. The walls of collenchyma cells are strengthened by the deposit of cellulose and the coating with pectin. These strengthenings are often restricted to single parts or edges of the cell.
Which of the is true for displacement?
A. It cannot be zero.
B. Its magnitude is greater than the distance travelled by the object.
C. It’s the shortest distance between initial & final position.
D. It is a vector quantity.- a)A, B and C are correct
- b)A and B are correct
- c)All of these
- d)C and D are correct
Correct answer is option 'D'. Can you explain this answer?
Which of the is true for displacement?
A. It cannot be zero.
B. Its magnitude is greater than the distance travelled by the object.
C. It’s the shortest distance between initial & final position.
D. It is a vector quantity.
A. It cannot be zero.
B. Its magnitude is greater than the distance travelled by the object.
C. It’s the shortest distance between initial & final position.
D. It is a vector quantity.
a)
A, B and C are correct
b)
A and B are correct
c)
All of these
d)
C and D are correct
|
|
Amrutha Mukherjee answered |
Can be negative.D. It is always equal to the distance travelled by the object.
The ratio of speed to the magnitude of velocity when the body is moving in one direction is- a)equal to one
- b)greater than or equal to one
- c)less than one
- d)greater than one
Correct answer is option 'A'. Can you explain this answer?
The ratio of speed to the magnitude of velocity when the body is moving in one direction is
a)
equal to one
b)
greater than or equal to one
c)
less than one
d)
greater than one
|
|
Radha Iyer answered |
Explanation:
When an object is moving in one direction, the speed and velocity of the object have the same magnitude but different directions. The ratio of speed to the magnitude of velocity can be calculated as follows:
1. Speed is defined as the distance traveled per unit of time, and it is a scalar quantity. It only takes into account the magnitude of the displacement.
2. Velocity, on the other hand, is defined as the rate of change of displacement over time, and it is a vector quantity. It takes into account both the magnitude and direction of displacement.
3. Since the object is moving in one direction, the magnitude of the velocity will be equal to the speed.
4. Therefore, the ratio of speed to the magnitude of velocity will be equal to 1, since the magnitudes are the same.
5. In other words, the speed and magnitude of velocity will have the same numerical value.
Answer: A. Equal to one
When an object is moving in one direction, the speed and velocity of the object have the same magnitude but different directions. The ratio of speed to the magnitude of velocity can be calculated as follows:
1. Speed is defined as the distance traveled per unit of time, and it is a scalar quantity. It only takes into account the magnitude of the displacement.
2. Velocity, on the other hand, is defined as the rate of change of displacement over time, and it is a vector quantity. It takes into account both the magnitude and direction of displacement.
3. Since the object is moving in one direction, the magnitude of the velocity will be equal to the speed.
4. Therefore, the ratio of speed to the magnitude of velocity will be equal to 1, since the magnitudes are the same.
5. In other words, the speed and magnitude of velocity will have the same numerical value.
Answer: A. Equal to one
Match the following with the correct response:
- a)(a) - (i), (b) - (iii),(c) (h), (c0 - (iv)
- b)(a) - (ii), (b) - (iv),(c) - (i), (d) - (iii)
- c)(a) - (iii), (b) - (ii).(c) - (iv), (d) - (i)
- d)(a) - (iv), (b) - (i),(c) - (iii), (d) - (ii)
Correct answer is option 'D'. Can you explain this answer?
Match the following with the correct response:
a)
(a) - (i), (b) - (iii),(c) (h), (c0 - (iv)
b)
(a) - (ii), (b) - (iv),(c) - (i), (d) - (iii)
c)
(a) - (iii), (b) - (ii).(c) - (iv), (d) - (i)
d)
(a) - (iv), (b) - (i),(c) - (iii), (d) - (ii)
|
|
Swati Verma answered |
i. Friction is the force that makes it difficult for one object to slide along the surface of another.
ii. The limiting friction is the frictional force just sufficient to move the object.
iii. Sliding friction refers to the resistance created by two objects sliding against each other.
iv. Rolling friction refers to the resistance created by an object rolling across a surface.
ii. The limiting friction is the frictional force just sufficient to move the object.
iii. Sliding friction refers to the resistance created by two objects sliding against each other.
iv. Rolling friction refers to the resistance created by an object rolling across a surface.
Find the incorrect statement about Newton’s law of action and reaction. Action and reaction:- a)are equal in magnitude
- b)act on the same bodies
- c)act simultaneously
- d)are different in direction
Correct answer is option 'B'. Can you explain this answer?
Find the incorrect statement about Newton’s law of action and reaction. Action and reaction:
a)
are equal in magnitude
b)
act on the same bodies
c)
act simultaneously
d)
are different in direction
|
Janhavi Ahuja answered |
Understanding Newton's Law of Action and Reaction
Newton’s third law states that for every action, there is an equal and opposite reaction. This principle is foundational in physics and can be broken down into several key points.
Key Characteristics of Action and Reaction
- Equal Magnitude: Action and reaction forces are equal in size. This means that if Object A exerts a force of 10 N on Object B, then Object B exerts a force of 10 N back on Object A.
- Opposite Direction: Action and reaction forces act in opposite directions. If Object A pushes to the right, Object B is pushed to the left with the same force.
- Simultaneous Action: These forces occur at the same time. When one object exerts a force, the other immediately responds with an equal and opposite force.
Why Option B is Incorrect
- Act on Different Bodies: The most crucial point is that action and reaction forces act on different bodies. For example, when a person jumps off a boat, the action of the person pushing down on the boat results in the reaction of the boat pushing up on the person. These forces are equal but act on different entities (the person and the boat), which is why option B is incorrect.
Conclusion
Newton's law of action and reaction highlights the interconnectedness of forces and their effects on different objects. Understanding this principle is essential for grasping fundamental concepts in physics and mechanics.
Newton’s third law states that for every action, there is an equal and opposite reaction. This principle is foundational in physics and can be broken down into several key points.
Key Characteristics of Action and Reaction
- Equal Magnitude: Action and reaction forces are equal in size. This means that if Object A exerts a force of 10 N on Object B, then Object B exerts a force of 10 N back on Object A.
- Opposite Direction: Action and reaction forces act in opposite directions. If Object A pushes to the right, Object B is pushed to the left with the same force.
- Simultaneous Action: These forces occur at the same time. When one object exerts a force, the other immediately responds with an equal and opposite force.
Why Option B is Incorrect
- Act on Different Bodies: The most crucial point is that action and reaction forces act on different bodies. For example, when a person jumps off a boat, the action of the person pushing down on the boat results in the reaction of the boat pushing up on the person. These forces are equal but act on different entities (the person and the boat), which is why option B is incorrect.
Conclusion
Newton's law of action and reaction highlights the interconnectedness of forces and their effects on different objects. Understanding this principle is essential for grasping fundamental concepts in physics and mechanics.
Lignified or thickened cell wall is a characteristic feature of- a)phloem
- b)xylem
- c)parenchyma
- d)collenchyma
Correct answer is option 'B'. Can you explain this answer?
Lignified or thickened cell wall is a characteristic feature of
a)
phloem
b)
xylem
c)
parenchyma
d)
collenchyma
|
|
Swati Verma answered |
The xylem is one of the conductive tissues in plants. It is a complex tissue composed of many types of cells. The main function of xylem is to conduct water and minerals from roots to leaves. The secondary xylem also provides mechanical support due to the presence of a thick lignified cell wall.
Which of the following lacks nucleus?- a)WBC
- b)Nerve cell
- c)Muscle cell
- d)RBC
Correct answer is option 'D'. Can you explain this answer?
Which of the following lacks nucleus?
a)
WBC
b)
Nerve cell
c)
Muscle cell
d)
RBC
|
|
Swati Verma answered |
RBC is called as red blood corpuscles. Red Blood Cells in mammals anucleate when mature i.e. they do not contain a nucleus. This is so that the cell has maximum space for haemoglobin.
A student by mistake mixed iron filings and sulphur powder. He wanted to separate them from each other. The method you would advise him to use it to dissolve the mixture in- a)carbon disulphide
- b)kerosene
- c)cold water
- d)boiling water
Correct answer is option 'A'. Can you explain this answer?
A student by mistake mixed iron filings and sulphur powder. He wanted to separate them from each other. The method you would advise him to use it to dissolve the mixture in
a)
carbon disulphide
b)
kerosene
c)
cold water
d)
boiling water
|
|
Swati Verma answered |
Addition of carbon disulphide to a mixture containing iron filings and sulphur powder leads to the formation of a clear yellow solution when sulphur powder dissolves in carbon disulphide, on gentle shaking. Iron fillings being insoluble settle in the bottom. These can be separated by filtration. When the solution is allowed to evaporate, the powder of solid sulphur is obtained.
Assertion (A): When astronauts throw something in space, that object would continue moving in the same direction and with the same speed.
Reason (R): The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true but R is not the correct explanation of A.
- c)A is true but R is false.
- d)A is false but R is true.
Correct answer is option 'B'. Can you explain this answer?
Assertion (A): When astronauts throw something in space, that object would continue moving in the same direction and with the same speed.
Reason (R): The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.
Reason (R): The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.
a)
Both A and R are true and R is the correct explanation of A.
b)
Both A and R are true but R is not the correct explanation of A.
c)
A is true but R is false.
d)
A is false but R is true.
|
|
Yashasvi Reddy answered |
**Assertion (A):** When astronauts throw something in space, that object would continue moving in the same direction and with the same speed.
**Reason (R):** The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.
The correct answer is option 'B' - Both A and R are true but R is not the correct explanation of A.
Explanation:
**Astronauts throwing something in space:**
When astronauts throw something in space, the object will continue moving in the same direction and with the same speed unless acted upon by an external force. This is due to the absence of significant forces such as air resistance or friction in space.
**Acceleration and Net Applied Force:**
The acceleration of an object is directly related to the magnitude of the net applied force and inversely related to the mass of the object. This relationship is described by Newton's second law of motion, which states that the acceleration of an object is equal to the net force acting on it divided by its mass (a = F/m).
In space, when an astronaut throws an object, they apply a force to it. According to Newton's third law of motion, the object exerts an equal and opposite force on the astronaut. As a result, the object accelerates in the direction of the force applied by the astronaut.
**Explanation of the Reason (R):**
The Reason (R) correctly states that the acceleration of an object is directly related to the magnitude of the force and inversely related to the mass of the object. However, it does not provide a direct explanation for why the object would continue moving in the same direction and with the same speed after being thrown in space.
**Conclusion:**
In conclusion, both the Assertion (A) and the Reason (R) are true. However, the Reason (R) does not provide a correct explanation for the Assertion (A). When astronauts throw something in space, the object will continue moving in the same direction and with the same speed due to the absence of significant external forces like air resistance or friction.
**Reason (R):** The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.
The correct answer is option 'B' - Both A and R are true but R is not the correct explanation of A.
Explanation:
**Astronauts throwing something in space:**
When astronauts throw something in space, the object will continue moving in the same direction and with the same speed unless acted upon by an external force. This is due to the absence of significant forces such as air resistance or friction in space.
**Acceleration and Net Applied Force:**
The acceleration of an object is directly related to the magnitude of the net applied force and inversely related to the mass of the object. This relationship is described by Newton's second law of motion, which states that the acceleration of an object is equal to the net force acting on it divided by its mass (a = F/m).
In space, when an astronaut throws an object, they apply a force to it. According to Newton's third law of motion, the object exerts an equal and opposite force on the astronaut. As a result, the object accelerates in the direction of the force applied by the astronaut.
**Explanation of the Reason (R):**
The Reason (R) correctly states that the acceleration of an object is directly related to the magnitude of the force and inversely related to the mass of the object. However, it does not provide a direct explanation for why the object would continue moving in the same direction and with the same speed after being thrown in space.
**Conclusion:**
In conclusion, both the Assertion (A) and the Reason (R) are true. However, the Reason (R) does not provide a correct explanation for the Assertion (A). When astronauts throw something in space, the object will continue moving in the same direction and with the same speed due to the absence of significant external forces like air resistance or friction.
Equation of motion can be used for a body having:- a)uniform acceleration
- b)non-uniform acceleration
- c)uniform motion
- d)non-uniform motion
Correct answer is option 'A'. Can you explain this answer?
Equation of motion can be used for a body having:
a)
uniform acceleration
b)
non-uniform acceleration
c)
uniform motion
d)
non-uniform motion
|
|
Aditi Sharma answered |
Relation among velocity, distance, time, and acceleration is called equations of motion. There are three equations of motion. Equation of motion can be used for a body having uniform acceleration.
Complete the sentence. Friction always ____________ - a)works in direction of motion
- b)opposes the direction of motion
- c)both of these
- d)none of these
Correct answer is option 'B'. Can you explain this answer?
Complete the sentence. Friction always ____________
a)
works in direction of motion
b)
opposes the direction of motion
c)
both of these
d)
none of these
|
|
Imk Pathshala answered |
- Friction always opposes the motion.
- Friction is a force that acts in the opposite direction to the movement of an object.
- It resists the relative motion between two surfaces in contact.
- This opposing force can slow down or stop objects in motion.
- While friction can be useful (e.g., providing traction for walking), its fundamental nature is to resist motion between surfaces.
- Friction is a force that acts in the opposite direction to the movement of an object.
- It resists the relative motion between two surfaces in contact.
- This opposing force can slow down or stop objects in motion.
- While friction can be useful (e.g., providing traction for walking), its fundamental nature is to resist motion between surfaces.
Which of the following options is a colloidal solution that exhibits the Tyndall effect?- a)Tinture iodine
- b)Egg white
- c)Milk
- d)Starch solution
Correct answer is option 'C'. Can you explain this answer?
Which of the following options is a colloidal solution that exhibits the Tyndall effect?
a)
Tinture iodine
b)
Egg white
c)
Milk
d)
Starch solution
|
|
Imk Pathshala answered |
The Tyndall effect is observed when light is scattered by particles in a colloidal solution. It is not seen in true solutions.
- Milk, egg white, and starch solution are examples of colloids. They can scatter light, showing the Tyndall effect. Among these, milk is a well-known colloidal solution that exhibits the Tyndall effect.
- Tincture iodine is a true solution and does not exhibit this effect, as its particles are too small to scatter light.
Conversion of solid directly into its vapour form is called:- a)evaporation
- b)vaporisation
- c)distillation
- d)sublimation
Correct answer is option 'D'. Can you explain this answer?
Conversion of solid directly into its vapour form is called:
a)
evaporation
b)
vaporisation
c)
distillation
d)
sublimation
|
|
Swati Verma answered |
Sublimation is the phase transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase.
Branched involuntary muscles fibres are found in- a)ureters
- b)limbs
- c)heart
- d)tongue
Correct answer is option 'C'. Can you explain this answer?
Branched involuntary muscles fibres are found in
a)
ureters
b)
limbs
c)
heart
d)
tongue
|
|
Swati Verma answered |
Involuntary muscles are found in walls of hollow tubular organs like an alimentary canal, ducts of glands, urogenital ducts, and blood vessels except the heart. They show slow contractions but remain contracted for a long period of time.
Read the text carefully and answer the questions:
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
Q. Which of the following is not the property of colloid?- a)Colloids are big enough to scatter a beam of light passing through it.
- b)A colloid is a heterogeneous mixture.
- c)Size of particles of a colloid is too small
- d)A colloid is very unstable
Correct answer is option 'D'. Can you explain this answer?
Read the text carefully and answer the questions:
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
Q. Which of the following is not the property of colloid?
a)
Colloids are big enough to scatter a beam of light passing through it.
b)
A colloid is a heterogeneous mixture.
c)
Size of particles of a colloid is too small
d)
A colloid is very unstable
|
Let's Tute answered |
- Colloids are stable mixtures, unlike suspensions, which can separate over time.
- They are heterogeneous at a microscopic level but appear homogeneous to the naked eye.
- Colloid particles are small enough to remain suspended and do not settle down.
- The particles are big enough to scatter light, showing the Tyndall effect.
A particle covers equal distances in equal intervals of time. It is said to be- a)Moving with constant speed
- b)Moving with constant acceleration
- c)Moving with variable acceleration
- d)At rest
Correct answer is option 'A'. Can you explain this answer?
A particle covers equal distances in equal intervals of time. It is said to be
a)
Moving with constant speed
b)
Moving with constant acceleration
c)
Moving with variable acceleration
d)
At rest
|
|
Swati Verma answered |
If a body covers equal distance in equal intervals of time then it is said to be moving at a uniform speed. Mathematically speed is defined as v = S/t , where v is the speed of the object, S is the distance covered and t is the time taken.
Read the text carefully and answer the questions:
In the velocity-time graph of an object that moves under uniform acceleration as the initial velocity of the object is u (at point A) and then it increases to v (at point B) in time t. The velocity changes at a uniform rate a.
Q. A car is moving along a straight road with uniform velocity. It is shown in the graph.- a)
- b)
- c)
- d)
Correct answer is option 'A'. Can you explain this answer?
Read the text carefully and answer the questions:
In the velocity-time graph of an object that moves under uniform acceleration as the initial velocity of the object is u (at point A) and then it increases to v (at point B) in time t. The velocity changes at a uniform rate a.
In the velocity-time graph of an object that moves under uniform acceleration as the initial velocity of the object is u (at point A) and then it increases to v (at point B) in time t. The velocity changes at a uniform rate a.
Q. A car is moving along a straight road with uniform velocity. It is shown in the graph.
a)
b)
c)
d)
|
EduRev Class 9 answered |
In the velocity-time graph of an object moving with uniform acceleration:
The car's movement is characterised by:
- Uniform Velocity: The car maintains a constant speed along a straight road.
- Graph Representation: The graph shows a horizontal line, indicating no change in velocity over time.
- No Acceleration: Since the velocity is constant, there is no acceleration involved.
This is shown in option A of the provided graphs.
Which of the following plant tissues do not possess living protoplasm at maturity?- a)Collenehyma
- b)Trachea
- c)Epidermis
- d)Sclerenchyma
Correct answer is option 'D'. Can you explain this answer?
Which of the following plant tissues do not possess living protoplasm at maturity?
a)
Collenehyma
b)
Trachea
c)
Epidermis
d)
Sclerenchyma
|
|
Aditi Sharma answered |
Sclerenchyma is permanent tissue present in different parts of plants. They are thick-walled and do not possess living protoplasm at maturity because these are dead.
Read the text carefully and answer the questions:
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
Q. A mixture of sulphur and carbon disulphide is:- a)Homogeneous and does not show Tyndall effect
- b)Heterogeneous and does not show Tyndall effect
- c)Heterogeneous and shows Tyndall effect
- d)Homogeneous and shows Tyndall effect
Correct answer is option 'A'. Can you explain this answer?
Read the text carefully and answer the questions:
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
A suspension is a heterogeneous mixture in which the solute particles do not dissolve but remain suspended throughout the bulk of the medium. Particles of a suspension are visible to the naked eye. The particles of a suspension scatter a beam of light passing through it and make its path visible. Due to the relatively smaller size of particles, as compared to that of a suspension, the mixture appears to be homogeneous. The scattering of a beam of light is called the Tyndall effect. The components of a colloidal solution are the dispersed phase and the dispersion medium. The solute-like component or the dispersed particles in a colloid form the dispersed phase, and the component in which the dispersed phase is suspended is known as the dispersing medium.
Q. A mixture of sulphur and carbon disulphide is:
a)
Homogeneous and does not show Tyndall effect
b)
Heterogeneous and does not show Tyndall effect
c)
Heterogeneous and shows Tyndall effect
d)
Homogeneous and shows Tyndall effect
|
|
Imk Pathshala answered |
- A mixture of sulphur and carbon disulphide is homogeneous.
- In a homogeneous mixture, the components are evenly distributed and appear as a single phase.
- This mixture does not show the Tyndall effect because the particles are too small to scatter light.
The correct statement about the object moving along a straight path with an accelerated motion is
A. Its velocity keeps changing
B. Its speed keeps changing
C. A force is always acting on it
D. Its mass keeps on changing- a)B, C and D
- b)A, B and C
- c)A, B and D
- d)All of these
Correct answer is option 'B'. Can you explain this answer?
The correct statement about the object moving along a straight path with an accelerated motion is
A. Its velocity keeps changing
B. Its speed keeps changing
C. A force is always acting on it
D. Its mass keeps on changing
A. Its velocity keeps changing
B. Its speed keeps changing
C. A force is always acting on it
D. Its mass keeps on changing
a)
B, C and D
b)
A, B and C
c)
A, B and D
d)
All of these
|
|
Aditi Sharma answered |
The object moving along a straight path with an accelerated motion has changing velocity, speed and mass.
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