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All questions of Cell Structure for Grade 12 Exam
Which cell organelle is present in both prokaryotic and eukaryotic cells?
- a)Mitochondria
- b)Endoplasmic reticulum
- c)Nucleus
- d)Ribosomes
Correct answer is option 'D'. Can you explain this answer?
Which cell organelle is present in both prokaryotic and eukaryotic cells?
a)
Mitochondria
b)
Endoplasmic reticulum
c)
Nucleus
d)
Ribosomes
|
Hansa Sharma answered |
- Prokaryotes and eukaryotes are the two different types of cells.
- Eukaryotic cells contain membrane-bound organelles, such as the nucleus, endoplasmic reticulum, mitochondria while prokaryotic cells do not but the ribosome is the only organelle that can be seen in both prokaryotic and eukaryotic cells.
- Prokaryotic and eukaryotic ribosomes perform the same functions that is protein synthesis, however, eukaryotic ribosomes are much larger than prokaryotic ones.
Which one of the following cell organelles is enclosed by a single membrane ? [2016]- a)Mitochondria
- b)Chloroplasts
- c)Lysosomes
- d)Nuclei
Correct answer is option 'C'. Can you explain this answer?
Which one of the following cell organelles is enclosed by a single membrane ? [2016]
a)
Mitochondria
b)
Chloroplasts
c)
Lysosomes
d)
Nuclei
|
Sushant Goyal answered |
(c) Double Membrane bound Organelles: Mitochondria, Chloroplasts, Endoplasmic Reticulum, Golgi Body, and Nucleus. Single Membrane bound Organelles: Lysosomes, Peroxisomes, and Vacuoles. Organelles lacking any membrane: Ribosomes, Centrioles, Nucleolus.
The largest subunit of prokaryotic ribosomes is- a)40S
- b)60S
- c)30S
- d)50S
Correct answer is 'D'. Can you explain this answer?
The largest subunit of prokaryotic ribosomes is
a)
40S
b)
60S
c)
30S
d)
50S
|
Shreya Gupta answered |
50S, roughly equivalent to the 60S ribosomal subunit in eukaryotic cells, is the larger subunit of the 70S ribosome of prokaryotes. The 50S subunit is primarily composed of proteins but also contains single-stranded RNA known as ribosomal RNA (rRNA).
Which of the following is a prokaryote?- a)Bacteria
- b)Amoeba
- c)Chlamydomonas
- d)Spirogyra
Correct answer is option 'A'. Can you explain this answer?
Which of the following is a prokaryote?
a)
Bacteria
b)
Amoeba
c)
Chlamydomonas
d)
Spirogyra
|
|
Hansa Sharma answered |
Prokaryotic cells are cells that do not have a true nucleus or most other cell organelles. Organisms that have prokaryotic cells are unicellular and called prokaryotes. Bacteria and archaea are prokaryotes.
Glycocalyx is associated with ___________
- a)Nucleosome
- b)Nucleus
- c)Plasma membrane
- d)Nucleolus
Correct answer is option 'C'. Can you explain this answer?
Glycocalyx is associated with ___________
a)
Nucleosome
b)
Nucleus
c)
Plasma membrane
d)
Nucleolus
|
Preeti Iyer answered |
The glycocalyx is a thick outer covering of the plasma membrane. It is composed of strands of sugars and proteins bound together. The result is a thick, sticky layer that helps cells stay put in environments with lots of physical stress.
Each question consists of two statements, namely, Assertion (A) and Reason (R).Assertion (A): Prokaryotic cells have no membrane-bound organelles.
Reason (R): The cytoplasm of prokaryotic cells does not show a streaming movement.For selecting the correct answer, use the following code:- a)Both assertion and reason are correct and the reason is the correct explanation for assertion
- b)Assertion is correct but the reason is incorrect.
- c)Both assertion and reason are correct but the reason is not the correct explanation for the assertion.
- d)Both assertion and reason are incorrect.
Correct answer is option 'A'. Can you explain this answer?
Each question consists of two statements, namely, Assertion (A) and Reason (R).
Assertion (A): Prokaryotic cells have no membrane-bound organelles.
Reason (R): The cytoplasm of prokaryotic cells does not show a streaming movement.
Reason (R): The cytoplasm of prokaryotic cells does not show a streaming movement.
For selecting the correct answer, use the following code:
a)
Both assertion and reason are correct and the reason is the correct explanation for assertion
b)
Assertion is correct but the reason is incorrect.
c)
Both assertion and reason are correct but the reason is not the correct explanation for the assertion.
d)
Both assertion and reason are incorrect.
|
|
Prasenjit Chavan answered |
Explanation:
• Prokaryotic cells, which are found in bacteria and archaea, lack the membrane-bound organelles that are present in eukaryotic cells. These organelles include the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes.
• The cytoplasm of prokaryotic cells does not show a streaming movement, which is a characteristic of eukaryotic cells. In eukaryotic cells, the cytoplasmic streaming is driven by motor proteins that move along actin filaments and microtubules.
• The absence of membrane-bound organelles in prokaryotic cells is related to their small size and simpler structure. They are able to carry out all their necessary functions within the cytoplasm without the need for specialized compartments.
• The lack of cytoplasmic streaming in prokaryotic cells is also related to their small size, as diffusion is sufficient for most of their metabolic processes.
Assertion (A): Prokaryotic cells have no membrane-bound organelles.
Reason (R): The cytoplasm of prokaryotic cells does not show a streaming movement.
The correct answer is option 'A'. Both the assertion and reason are correct, and the reason is the correct explanation for the assertion.
• Prokaryotic cells, which are found in bacteria and archaea, lack the membrane-bound organelles that are present in eukaryotic cells. These organelles include the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes.
• The cytoplasm of prokaryotic cells does not show a streaming movement, which is a characteristic of eukaryotic cells. In eukaryotic cells, the cytoplasmic streaming is driven by motor proteins that move along actin filaments and microtubules.
• The absence of membrane-bound organelles in prokaryotic cells is related to their small size and simpler structure. They are able to carry out all their necessary functions within the cytoplasm without the need for specialized compartments.
• The lack of cytoplasmic streaming in prokaryotic cells is also related to their small size, as diffusion is sufficient for most of their metabolic processes.
Assertion (A): Prokaryotic cells have no membrane-bound organelles.
Reason (R): The cytoplasm of prokaryotic cells does not show a streaming movement.
The correct answer is option 'A'. Both the assertion and reason are correct, and the reason is the correct explanation for the assertion.
Which is common in plant and animal cells- a)Mitochondria
- b)Plastids
- c)Centrioles
- d)Central vacuoles
Correct answer is option 'A'. Can you explain this answer?
Which is common in plant and animal cells
a)
Mitochondria
b)
Plastids
c)
Centrioles
d)
Central vacuoles
|
Ashwini Khanna answered |
Mitochondria are present in both plant as well as animal cells. Plastids and central vacuoles are present in plant cells and centrioles are present in only animal cells.
The process of movement of few ions or molecules across the membrane against a concentration gradient from lower to higher concentration, it is called
a) Diffusionb)Passive transportc)Active transportd) OsmosisCorrect answer is option 'C'. Can you explain this answer?
|
Vijay Bansal answered |
Passive transport, also known as passive diffusion, is a process by which an ion or molecule passes through a cell wall via a concentration gradient, or from an area of high concentration to an area of low concentration. It’s like moving from the train to the platform of a subway station, or stepping out of a crowded room. Basically, passive transport gives an ion or molecule “room to breathe.”
Which structures perform the function of mitochondria in bacteria? [2014]- a)Nucleoid
- b)Ribosomes
- c)Cell wall
- d)Mesosomes
Correct answer is option 'D'. Can you explain this answer?
Which structures perform the function of mitochondria in bacteria? [2014]
a)
Nucleoid
b)
Ribosomes
c)
Cell wall
d)
Mesosomes
|
Ayush Sengupta answered |
(d) In some bacteria (e.g., Bacillus subtilis) the plasma membrane form certain invaginations or in foldings called mesosomes in the cytoplasm. The mesosomes have various functions, viz., respiratory, secretory etc.
Can you explain the answer of this question below:Organisms which lack mitosis division and use binary fission method for cell division are known as
- A:
prokaryotes
- B:
eukaryotes
- C:
yeast
- D:
fungi
The answer is a.
Organisms which lack mitosis division and use binary fission method for cell division are known as
prokaryotes
eukaryotes
yeast
fungi
|
Neha Joshi answered |
- As in prokaryotes, centrioles are absent.
- Centrioles play an important part in mitosis during spindle fibre formation. so mitosis is not seen in them, thus they use binary fission.
Cell organelles with single membrane is- a)Lysosomes
- b)Chloroplast
- c)Plastids
- d)Mitochondria
Correct answer is option 'A'. Can you explain this answer?
Cell organelles with single membrane is
a)
Lysosomes
b)
Chloroplast
c)
Plastids
d)
Mitochondria
|
Ishaan Menon answered |
Lysosomes are single membrane structures containing enzymes for digestion of all types of macromolecules.
Can you explain the answer of this question below:Maximum enzymes are found in:-
- A:
Lysosomes
- B:
Mitochondria
- C:
Nucleus
- D:
E.R.
The answer is b.
Maximum enzymes are found in:-
Lysosomes
Mitochondria
Nucleus
E.R.
|
Navya Sengupta answered |
Mitochondria is the site for aerobic respiration in cell and produces energy in the form of ATP. For the formation of energy different pathways like electron transport chain, kreb's cycle are involved and operated by the different enzymes. Thus, the maximum number of enzymes are found in mitochondria.
Select the correct matching in the following pairs: [2015 RS]- a)Smooth ER – Synthesis of lipids
- b)Rough ER – Synthesis of glycogen
- c)Rough ER – Oxidation of fatty acids
- d)Smooth ER – Oxidation of phospholipids
Correct answer is option 'A'. Can you explain this answer?
Select the correct matching in the following pairs: [2015 RS]
a)
Smooth ER – Synthesis of lipids
b)
Rough ER – Synthesis of glycogen
c)
Rough ER – Oxidation of fatty acids
d)
Smooth ER – Oxidation of phospholipids
|
Pallabi Reddy answered |
(a) Lipid synthesis takes place in smooth endoplasmic reticulum.
Which of the following are not membranebound? [2015 RS]- a)Ribosomes
- b)Lysosomes
- c)Mesosomes
- d)Vacuoles
Correct answer is option 'A'. Can you explain this answer?
Which of the following are not membranebound? [2015 RS]
a)
Ribosomes
b)
Lysosomes
c)
Mesosomes
d)
Vacuoles
|
Mrinalini Bajaj answered |
(a) Ribosomes are not membrance-bound cell organelle.
Who was the first to explain that cells divide?
- a)Schwann
- b)Robert Brown
- c)Rudolf Virchow
- d)Anton von LeeuwenHoek
Correct answer is option 'C'. Can you explain this answer?
Who was the first to explain that cells divide?
a)
Schwann
b)
Robert Brown
c)
Rudolf Virchow
d)
Anton von LeeuwenHoek
|
Mahesh Saini answered |
Rudolf Virchow(1855) first explained that cells divided and new cells are formed .
Nuclear membrane is absent in- a)Nostoc
- b)Penicillium
- c)Volvox
- d)Agaricus
Correct answer is option 'A'. Can you explain this answer?
Nuclear membrane is absent in
a)
Nostoc
b)
Penicillium
c)
Volvox
d)
Agaricus
|
Rohit Shah answered |
Nostoc, genus of blue-green algae with cells arranged in beadlike chains that are grouped together in a gelatinous mass. Ranging from microscopic to walnut-sized, masses of Nostoc may be found on soil and floating in quiet water. Reproduction is by fragmentation. A special thick-walled cell (akinete) has the ability to withstand desiccation for long periods of time. After 70 years of dry storage, the akinete of one species germinates into a filament when moistened. Like most blue-green algae, Nostoc contains two pigments, blue phycocyanin and red phycoerythrin, as well as chlorophyll, and has the ability to fix nitrogen in specialized cells called heterocysts. A terrestrial species has been used as a supplementary food source in Asia.
Read the given statements and select the correct option.
Statement 1: The cisternae in Golgi complex have cis face and trans face.
Statement 2: The cis face is also called forming face and trans face is also called maturing face.- a)Both statements 1 and 2 are correct and statement 2 is the correct explanation of statement 1.
- b)Both statements 1 and 2 are correct but statement 2 is not the correct explanation of statement 1.
- c)Statement 1 is correct and statement 2 is incorrect.
- d)Both statements 1 and 2 are incorrect.
Correct answer is option 'B'. Can you explain this answer?
Read the given statements and select the correct option.
Statement 1: The cisternae in Golgi complex have cis face and trans face.
Statement 2: The cis face is also called forming face and trans face is also called maturing face.
Statement 1: The cisternae in Golgi complex have cis face and trans face.
Statement 2: The cis face is also called forming face and trans face is also called maturing face.
a)
Both statements 1 and 2 are correct and statement 2 is the correct explanation of statement 1.
b)
Both statements 1 and 2 are correct but statement 2 is not the correct explanation of statement 1.
c)
Statement 1 is correct and statement 2 is incorrect.
d)
Both statements 1 and 2 are incorrect.
|
|
Mayank Gupta answered |
Explanation:
Statement 1: The cisternae in Golgi complex have cis face and trans face.
The Golgi complex is an organelle found in eukaryotic cells that plays a key role in the processing and sorting of proteins and lipids. It consists of a series of flattened membrane-bound sacs called cisternae. These cisternae have two distinct faces - the cis face and the trans face.
Statement 2: The cis face is also called the forming face and the trans face is also called the maturing face.
The cis face of the Golgi complex is the side that is closest to the endoplasmic reticulum (ER), where newly synthesized proteins and lipids enter the Golgi. It is involved in receiving and sorting proteins and lipids from the ER. The cis face is also referred to as the forming face because it is where the Golgi complex receives and forms vesicles containing these proteins and lipids.
The trans face of the Golgi complex is the side that is farthest from the ER. It is involved in packaging proteins and lipids into vesicles that will be transported to their final destinations. The trans face is also referred to as the maturing face because it is where the Golgi complex modifies and matures these proteins and lipids before they are packaged into vesicles.
Conclusion:
Both statements 1 and 2 are correct, but statement 2 is not the correct explanation of statement 1. The cis face and trans face of the Golgi complex are indeed referred to as the forming face and maturing face, respectively, but these terms do not explain the function or location of the two faces. The cis face is where the Golgi complex receives and forms vesicles, while the trans face is where it packages and matures proteins and lipids. Therefore, the correct option is B.
Statement 1: The cisternae in Golgi complex have cis face and trans face.
The Golgi complex is an organelle found in eukaryotic cells that plays a key role in the processing and sorting of proteins and lipids. It consists of a series of flattened membrane-bound sacs called cisternae. These cisternae have two distinct faces - the cis face and the trans face.
Statement 2: The cis face is also called the forming face and the trans face is also called the maturing face.
The cis face of the Golgi complex is the side that is closest to the endoplasmic reticulum (ER), where newly synthesized proteins and lipids enter the Golgi. It is involved in receiving and sorting proteins and lipids from the ER. The cis face is also referred to as the forming face because it is where the Golgi complex receives and forms vesicles containing these proteins and lipids.
The trans face of the Golgi complex is the side that is farthest from the ER. It is involved in packaging proteins and lipids into vesicles that will be transported to their final destinations. The trans face is also referred to as the maturing face because it is where the Golgi complex modifies and matures these proteins and lipids before they are packaged into vesicles.
Conclusion:
Both statements 1 and 2 are correct, but statement 2 is not the correct explanation of statement 1. The cis face and trans face of the Golgi complex are indeed referred to as the forming face and maturing face, respectively, but these terms do not explain the function or location of the two faces. The cis face is where the Golgi complex receives and forms vesicles, while the trans face is where it packages and matures proteins and lipids. Therefore, the correct option is B.
When the centromere is situated in the middle of two equal arms of chromosomes, the chromosome is referred as: (2021)- a)Sub-metacentric
- b)Acrocentric
- c)Metacentric
- d)Telocentric
Correct answer is option 'C'. Can you explain this answer?
When the centromere is situated in the middle of two equal arms of chromosomes, the chromosome is referred as: (2021)
a)
Sub-metacentric
b)
Acrocentric
c)
Metacentric
d)
Telocentric
|
Mira Joshi answered |
The metacentric chromosome has middle centromere forming two equal arms of the chromosome.
Which cell organelle secretes zymogen granules :-a)Lysosomesb)Smooth E. R.c)Golgibodyd)SphaerosomesCorrect answer is option 'B'. Can you explain this answer?
|
|
Vijay Bansal answered |
The Golgi apparatus is a system of membranous cisternae and vesicles arranged in stacks near the nucleus. Secretory vesicles or granules usually contain specific substances synthesized by cells that are exported to the extracellular medium. They include zymogen granules, mucous droplets, and mast cell granules.
Rough E.R. mainly responsible for:-- a)Protein synthesis
- b)Cell wall formation
- c)Lipid synthesis
- d)Cholesterol synthesis
Correct answer is option 'A'. Can you explain this answer?
Rough E.R. mainly responsible for:-
a)
Protein synthesis
b)
Cell wall formation
c)
Lipid synthesis
d)
Cholesterol synthesis
|
|
Neha Joshi answered |
Rough endoplasmic reticulum carry ribosomes on their surface. The ribosomes present on rough endoplasmic reticulum synthesize secretory proteins. The proteins required for internal use of cell are synthesized on cytoplasmic ribosomes.
The chlorophyll pigment is readily soluble in:-- a)Water
- b)Acids
- c)Alkalies
- d)Acetone
Correct answer is option 'D'. Can you explain this answer?
The chlorophyll pigment is readily soluble in:-
a)
Water
b)
Acids
c)
Alkalies
d)
Acetone
|
|
Rajesh Gupta answered |
The chlorophyll pigment is readily soluble in acetone. Chlorophylls possess a phytyl chain which is bound to a porphyrin ring system. The possession of the phytyl side chain, which is esterified to the carboxyl group of the ring, gives the chlorophylls their lipid character. Moreover, chlorophylls are fat-soluble compounds that can be extracted from water-containing living plant tissue by organic solvents such as acetone, methanol, or ethanol, which can take up water.
Cellular organelles with membranes are : [2015 RS]- a)chormosomes, ribosomes and endoplasmic reticulum
- b)endoplasmic reticulum, ribosomes and nuclei
- c)lysosomes, Golgi apparatus and mitochondria
- d)nuclei, ribosomes and mitochondria
Correct answer is option 'C'. Can you explain this answer?
Cellular organelles with membranes are : [2015 RS]
a)
chormosomes, ribosomes and endoplasmic reticulum
b)
endoplasmic reticulum, ribosomes and nuclei
c)
lysosomes, Golgi apparatus and mitochondria
d)
nuclei, ribosomes and mitochondria
|
Sonal Kulkarni answered |
(c) Lysosomes, golgi apparatus and mitochondria are the cell organelles which have membranes.
Smallest free living organism are- a)PPLOs
- b)Bacteria
- c)Viroids
- d)Virus
Correct answer is option 'A'. Can you explain this answer?
Smallest free living organism are
a)
PPLOs
b)
Bacteria
c)
Viroids
d)
Virus
|
|
Rohan Singh answered |
Pelagibacter ubique is one of the smallest known free-living bacterium with a length of 0.37-0.89 μm and an average cell diameter of 0.12-0.20 μm. They also have the smallest free-living bacterium genome; 1.8Mbp, 1354 protein genes, 35 RNA genes.
A single unit membrane surrounds the organelle:- a)Chloroplast
- b)Nucleus
- c)Lysosome
- d)Microsome
Correct answer is option 'C'. Can you explain this answer?
A single unit membrane surrounds the organelle:
a)
Chloroplast
b)
Nucleus
c)
Lysosome
d)
Microsome
|
|
Pooja Mehta answered |
Single membrane-bound: Some organelles are bounded by a single membrane. For example, vacuole, lysosome, Golgi Apparatus, Endoplasmic Reticulum etc. They are present only in a eukaryotic cell.
The prokaryotic cells are characterised by- a)Presence of a distinct chromosome
- b)Absence of chromatin material
- c)Absence of a nuclear membrane
- d)Presence of a distinct nuclear membrane
Correct answer is option 'C'. Can you explain this answer?
The prokaryotic cells are characterised by
a)
Presence of a distinct chromosome
b)
Absence of chromatin material
c)
Absence of a nuclear membrane
d)
Presence of a distinct nuclear membrane
|
|
Vijay Bansal answered |
Prokaryotes lack an organized nucleus and other membrane-bound organelles. Prokaryotic DNA is found in a central part of the cell called the nucleoid. The cell wall of a prokaryote acts as an extra layer of protection, helps maintain cell shape, and prevents dehydration.prokaryotic cells are those that do not have a membrane-bound nucleus. In fact "pro-karyotic" is Greek for "before nucleus". Besides bacteria, the cyanobacteria (blue-green algae) are a major group of prokaryotes.
Eukaryotic cells are different from prokaryotic cells in having:
- a)
True nucleus
- b)Mitochondria in mesosome form
- c)Only smooth endoplasmic reticulum
- d)70S ribosomes
Correct answer is option 'A'. Can you explain this answer?
Eukaryotic cells are different from prokaryotic cells in having:
a)
True nucleus
b)
Mitochondria in mesosome form
c)
Only smooth endoplasmic reticulum
d)
70S ribosomes
|
Anjali Iyer answered |
Correct option is A)
- Eukaryotic cells have a true nucleus whereas prokaryotic cells have a primitive nucleus.
- The true nucleus of eukaryotes is a double membrane-covered protoplasmic body that contains hereditary information.
- A true nucleus is made up of five parts- nuclear envelope, nucleoplasm, nuclear matrix, chromatin, and nucleolus.
- The primitive nucleus of a prokaryote is also called as nucleoid as it lacks these parts. It is comprised of only the genetic material. So, option A is correct.
Protoplasm found inside the nucleus is known as- a)Amyloplast
- b)Nucleoplasm
- c)cytoplasm
- d)Elaioplast
Correct answer is option 'B'. Can you explain this answer?
Protoplasm found inside the nucleus is known as
a)
Amyloplast
b)
Nucleoplasm
c)
cytoplasm
d)
Elaioplast
|
|
Nandini Patel answered |
Protoplasm is the living content of a cell that is surrounded by a plasma membrane. It is a general term for the cytoplasm. Protoplasm is composed of a mixture of small molecules such as ions, amino acids, monosaccharides and water, and macromolecules such as nucleic acids, proteins, lipids and polysaccharides.Similar to the cytoplasm of a cell, the nucleus contains 'nucleoplasm' (nucleus sap) or karyoplasm. The nucleoplasm is one of the types of protoplasm, and it is enveloped by the nuclear membrane or nuclear envelope. The nucleoplasm includes the chromosomes and nucleoli.
The rod shaped bacteria is called as- a)Bacillus
- b)Vibrio
- c)Spiral
- d)Spherical
Correct answer is option 'A'. Can you explain this answer?
The rod shaped bacteria is called as
a)
Bacillus
b)
Vibrio
c)
Spiral
d)
Spherical
|
Dipanjan Chawla answered |
The shapes of bacteria are bacillus (rod like), coccus (spherical), vibrio (comma shaped) and spirillum (spiral).
The structure of plasma membrane fluid mosaic model is proposed by- a)Gram
- b)Singer and Nicolson
- c)Schwann and Schleiden
- d)Robert brown
Correct answer is option 'B'. Can you explain this answer?
The structure of plasma membrane fluid mosaic model is proposed by
a)
Gram
b)
Singer and Nicolson
c)
Schwann and Schleiden
d)
Robert brown
|
|
Rajeev Saxena answered |
An improved model of the structure of cell membrane was proposed by S.J. Singer and G.L. Nicolson (1972) widely accepted as fluid mosaic model.CORRECT OPTION IS B.
Phospholipid synthetase enzyme occur in :-- a)RER
- b)SER
- c)Golgibody
- d)Glyoxysome
Correct answer is option 'B'. Can you explain this answer?
Phospholipid synthetase enzyme occur in :-
a)
RER
b)
SER
c)
Golgibody
d)
Glyoxysome
|
|
Pooja Mehta answered |
There are two forms of this enzyme; one is found in the outer mitochondrial membrane, while the other is found in the endoplasmic reticulum. ... This occurs primarily in the endoplasmic reticulum. Phosphatidic acid can be used in the synthesis of several phospholipids by two different mechanisms.
Lysosomes are produced by- a)Leucoplast
- b)Golgi bodies
- c)Mitochondria
- d)Endoplasmic reticulum
Correct answer is option 'B'. Can you explain this answer?
Lysosomes are produced by
a)
Leucoplast
b)
Golgi bodies
c)
Mitochondria
d)
Endoplasmic reticulum
|
Rohan Unni answered |
These are membrane bound vesicular structures formed by the process of packaging in the Golgi apparatus.
Who first saw and described a live cell?- a)T. Schwann
- b)R. Virchow
- c)A.V. Leeuwenhoek
- d)M. Schleiden
Correct answer is option 'C'. Can you explain this answer?
Who first saw and described a live cell?
a)
T. Schwann
b)
R. Virchow
c)
A.V. Leeuwenhoek
d)
M. Schleiden
|
Deepak Joshi answered |
Anton Von Leeuwenhoek first saw and described a live cell.
Chlorophyll in chloroplasts is located in- a)Pyrenoid
- b)Both grana and stroma
- c)Grana
- d)Stroma
Correct answer is option 'C'. Can you explain this answer?
Chlorophyll in chloroplasts is located in
a)
Pyrenoid
b)
Both grana and stroma
c)
Grana
d)
Stroma
|
|
Raghav Bansal answered |
Correct Answer :- c
Explanation : Chloroplasts are structurally made up of two components- thylakoids (internal membrane structures) and stroma. Some of the thylakoid membranes are stacked one above the other and are called as grana. The grana contain light trapping pigment chlorophyll and are thus the site of light reaction.
Which of the following cell organelles store hydrolytic enzymes?- a)Chloroplasts
- b)Centrioles
- c)Chromoplasts
- d)Lysosomes
Correct answer is option 'D'. Can you explain this answer?
Which of the following cell organelles store hydrolytic enzymes?
a)
Chloroplasts
b)
Centrioles
c)
Chromoplasts
d)
Lysosomes
|
|
Hitakshi Tamta G answered |
Lysosomes are spherical bodies, or vacuoles that are enclosed by a single membrane (membrane- bound organelles). It contains different hydrolytic enzymes, such as proteases, lipases, and nucleases that are capable of breaking down all types of biological polymers (e.g., proteins, nucleic acids, carbohydrates, and lipids) that enter the cell or are no longer useful to the cell. So, the correct answer is 'Lysosome'.
Carbohydrates, the most abundant biomolecules on Earth, are produced by- a)Viruses, fungi and bacteria
- b)Fungi, algae and green plant cells
- c)Some bacteria, algae and green plant cells
- d)All bacteria, fungi and algae
Correct answer is option 'C'. Can you explain this answer?
Carbohydrates, the most abundant biomolecules on Earth, are produced by
a)
Viruses, fungi and bacteria
b)
Fungi, algae and green plant cells
c)
Some bacteria, algae and green plant cells
d)
All bacteria, fungi and algae
|
Rocky Handsome answered |
Carbohydrates are organic compounds synthesized in the chlorophyll containing cells of some bacteria,-algae and green plant cells, during photosynthesis. Certain photoautotrophic bacteria eg. Green sulphur bacteria and purple sulphur bacteria contain pigments like chlorobium chlorophyll and bacteriochlorophyll respectively that helps them in photosynthesis. During photosynthesis carbon dioxide is reduced into carbohydrates by water and oxygen is liberated.
so option C ) is correct
( . __ .)
How much percent of vacuoles occupy the volume of the cell in plant cells?- a)80%
- b)90%
- c)50%
- d)70%
Correct answer is option 'B'. Can you explain this answer?
How much percent of vacuoles occupy the volume of the cell in plant cells?
a)
80%
b)
90%
c)
50%
d)
70%
|
Arya Nair answered |
In plant cells the vacuoles can occupy up to 90 per cent of the volume of the cell.
Cristae are associated with which of the following?- a)Endoplasmic reticulum
- b)Mitochondria
- c)Protoplasm
- d)Cytoplasm
Correct answer is option 'B'. Can you explain this answer?
Cristae are associated with which of the following?
a)
Endoplasmic reticulum
b)
Mitochondria
c)
Protoplasm
d)
Cytoplasm
|
|
Stuti Sen answered |
**Mitochondria and Cristae**
The correct answer is option B: Mitochondria. Cristae are indeed associated with mitochondria.
**Explanation**
Mitochondria are double-membrane-bound organelles found in most eukaryotic cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of adenosine triphosphate (ATP), which is used as a source of chemical energy.
One important feature of mitochondria is their inner membrane, which is highly folded to form structures called cristae. Cristae are invaginations or inward folds of the inner mitochondrial membrane. These folds increase the surface area of the inner membrane, allowing for more space where ATP synthesis can occur.
**Function of Cristae**
The presence of cristae in mitochondria is crucial for their function. The inner membrane of the mitochondria contains the electron transport chain (ETC) complexes, which play a key role in generating ATP through aerobic respiration. The ETC complexes are responsible for transferring electrons from electron donors to electron acceptors, creating a proton gradient across the inner mitochondrial membrane. This proton gradient is then used to drive the synthesis of ATP.
The highly folded structure of cristae increases the surface area available for the ETC complexes and ATP synthase, which are embedded in the inner membrane. This allows for more efficient ATP production, as there is a higher concentration of these proteins in the cristae. The increased surface area also allows for more efficient electron transfer and proton pumping, further enhancing ATP synthesis.
**Summary**
Cristae are associated with mitochondria. They are invaginations or inward folds of the inner mitochondrial membrane. The presence of cristae increases the surface area of the inner membrane, allowing for more efficient ATP synthesis through the electron transport chain and ATP synthase.
The correct answer is option B: Mitochondria. Cristae are indeed associated with mitochondria.
**Explanation**
Mitochondria are double-membrane-bound organelles found in most eukaryotic cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of adenosine triphosphate (ATP), which is used as a source of chemical energy.
One important feature of mitochondria is their inner membrane, which is highly folded to form structures called cristae. Cristae are invaginations or inward folds of the inner mitochondrial membrane. These folds increase the surface area of the inner membrane, allowing for more space where ATP synthesis can occur.
**Function of Cristae**
The presence of cristae in mitochondria is crucial for their function. The inner membrane of the mitochondria contains the electron transport chain (ETC) complexes, which play a key role in generating ATP through aerobic respiration. The ETC complexes are responsible for transferring electrons from electron donors to electron acceptors, creating a proton gradient across the inner mitochondrial membrane. This proton gradient is then used to drive the synthesis of ATP.
The highly folded structure of cristae increases the surface area available for the ETC complexes and ATP synthase, which are embedded in the inner membrane. This allows for more efficient ATP production, as there is a higher concentration of these proteins in the cristae. The increased surface area also allows for more efficient electron transfer and proton pumping, further enhancing ATP synthesis.
**Summary**
Cristae are associated with mitochondria. They are invaginations or inward folds of the inner mitochondrial membrane. The presence of cristae increases the surface area of the inner membrane, allowing for more efficient ATP synthesis through the electron transport chain and ATP synthase.
Chromatin is made up of :–- a)Nucleoprotein
- b)Nucleoside
- c)Pentose sugar
- d)Nitrogenous base
Correct answer is option 'A'. Can you explain this answer?
Chromatin is made up of :–
a)
Nucleoprotein
b)
Nucleoside
c)
Pentose sugar
d)
Nitrogenous base
|
|
Satakshi Kumari answered |
In eukaryotes , there is a set of positively charged , basic proteins called history. Histones are organized to form a unit of eight molecules called Histones octamer. The negativity charged, DNA is wrapped around the positively charged histone octamer to form a structure called nucleosome . Nucleosome constitute the repeating unit of a structure in nucleus called chromatin.
Mitochondrial DNA is :-- a)Naked
- b)Circular
- c)Double stranded
- d)All the above
Correct answer is option 'D'. Can you explain this answer?
Mitochondrial DNA is :-
a)
Naked
b)
Circular
c)
Double stranded
d)
All the above
|
|
Vijay Bansal answered |
This genetic material is known as mitochondrial DNA or mtDNA. In humans, mitochondrial DNA spans about 16,500 DNA building blocks (base pairs), representing a small fraction of the total DNA in cells. Mitochondrial DNA contains 37 genes, all of which are essential for normal mitochondrial function.
Which one is present nearest to plasmamembrane?- a)Secondary wall
- b)Tonoplast
- c)Middle lamella
- d)Primary wall
Correct answer is option 'A'. Can you explain this answer?
Which one is present nearest to plasmamembrane?
a)
Secondary wall
b)
Tonoplast
c)
Middle lamella
d)
Primary wall
|
Rajesh Datta answered |
The cell wall of a young plant cell, the primary wallis capable of growth, which gradually diminishes as the cell matures and the secondary wall is formed on the inner (towards membrane) side of the cell.
Animal cell do not possess- a)Centriole
- b)Plamsodesmata
- c)Ribosomes
- d)Plasmalemma
Correct answer is option 'B'. Can you explain this answer?
Animal cell do not possess
a)
Centriole
b)
Plamsodesmata
c)
Ribosomes
d)
Plasmalemma
|
Prisha Singh answered |
Animal cell do not possess plasmodesmata but it contain ribosomes, centriole andplamalemma. Plasmodesmata is the connection between two plant cells.
Small particles projecting from the inner membrane and cristae of mitochondria are- a)Oxysomes
- b)Microsomes
- c)Informosomes
- d)Myeloid bodies
Correct answer is option 'A'. Can you explain this answer?
Small particles projecting from the inner membrane and cristae of mitochondria are
a)
Oxysomes
b)
Microsomes
c)
Informosomes
d)
Myeloid bodies
|
C.k Singh answered |
Oxysomes are the structure present in the inner surface of mitochondra.it is also known as f0-f1particle or Atp synthese.oxysomes play an important role in formation energy for the functioning of the cell.oxysome help in the electron transport i.e oxidation and reduction rxn in respiration.
Which is the important site of formation of glycoproteins and glycolipids in eukaryotic cells? (2020)- a)Golgi bodies
- b)Polysomes
- c)Endoplasmic reticulum
- d)Peroxisomes
Correct answer is option 'A'. Can you explain this answer?
Which is the important site of formation of glycoproteins and glycolipids in eukaryotic cells? (2020)
a)
Golgi bodies
b)
Polysomes
c)
Endoplasmic reticulum
d)
Peroxisomes
|
|
Mira Joshi answered |
Proteins and lipids are formed in the endoplasmic reticulum and some of them are modified to form glycoproteins and glycolipids in the Golgi apparatus.
Cytoskeleton is made of- a)Phosphoglycerides
- b)Micro tubules
- c)Proteinaceousfilaments
- d)Hemicellulose
Correct answer is option 'C'. Can you explain this answer?
Cytoskeleton is made of
a)
Phosphoglycerides
b)
Micro tubules
c)
Proteinaceousfilaments
d)
Hemicellulose
|
|
Rajeev Saxena answered |
Proteinaceous filaments
The cytoplasm of all eukaryotic cells is crisscrossed by a network of protein fibres that support the shape of the cell and anchor organelles to fixed locations. It is a dynamic system with three types of fibres-actin filaments, microtubule and intermediate filaments.
Elaioplasts belongs to- a)Chloroplast
- b)Leucoplast
- c)Amyloplast
- d)Chromoplast
Correct answer is option 'B'. Can you explain this answer?
Elaioplasts belongs to
a)
Chloroplast
b)
Leucoplast
c)
Amyloplast
d)
Chromoplast
|
Arpita Tiwari answered |
The leucoplasts are the colourless plastids of varied shapes and sizes with stored nutrients. Leucoplast includes: a) Amyloplasts storing carbohydrates. b) Elaioplastsstoring oils and fats and c) Aleuroplasts storing proteins.
Lipid molecules of plasma membrane occur- a)Parallel
- b)In series
- c)Scattered
- d)Alternately
Correct answer is option 'A'. Can you explain this answer?
Lipid molecules of plasma membrane occur
a)
Parallel
b)
In series
c)
Scattered
d)
Alternately
|
Muskaan Basak answered |
The lipid molecules of plasma membrane occurs parallel to each other in plasma membrane of the cell.
Many cells function properly and divide mitotically even though they do not have- a)Plasma membrane
- b)Cytoskeleton
- c)Plastids
- d)Mitochondria
Correct answer is option 'C'. Can you explain this answer?
Many cells function properly and divide mitotically even though they do not have
a)
Plasma membrane
b)
Cytoskeleton
c)
Plastids
d)
Mitochondria
|
Prakhar Maheshwari answered |
Plastids have no role in mitotic division of a cell. They are only responsible for colors.
Eg;
Animal cells do not have plastids yet they can divide.
Which one of the following has its own DNA?- a)Mitochondria
- b)Dictyosome
- c)Lysosome
- d)Peroxisome
Correct answer is option 'A'. Can you explain this answer?
Which one of the following has its own DNA?
a)
Mitochondria
b)
Dictyosome
c)
Lysosome
d)
Peroxisome
|
Gaurav Kumar answered |
In mitochondria, the inner membrane space is filled with a matrix which contains dense granules along with ribosomes and mitochondrial DNA. The mitochondrial DNA is circular in nature. There number varies from 2-6. Besides DNA, a mitochondrion has RNA and its ribosomes also. Thus, a complete protein synthesizing machinery is present in mitochondria, which suggests the semi-autonomous nature of mitochondria. Dictyosome, lysosome and peroxisome do not have their own DNA.
Which ion holds the ribosomal subunits together- a)Ca+2
- b)Mn+2
- c)Mg+2
- d)Na+
Correct answer is option 'C'. Can you explain this answer?
Which ion holds the ribosomal subunits together
a)
Ca+2
b)
Mn+2
c)
Mg+2
d)
Na+
|
|
Hansa Sharma answered |
Owing to its abundance and highest charge density among all biological ions, magnesium is most suitable for neutralizing the negative charge density of RNA nucleotide backbone. Ribosomal subunits associate to form complete ribosome in presence of Mg ion.
Mitochondria are site of respiration first reported by Kingsbury and supported by Hogeboom.Mitochondria are related with the oxidation of :- a)Carbohydrates
- b)Fats
- c)Proteins
- d)All the above
Correct answer is option 'D'. Can you explain this answer?
Mitochondria are site of respiration first reported by Kingsbury and supported by Hogeboom.Mitochondria are related with the oxidation of :
a)
Carbohydrates
b)
Fats
c)
Proteins
d)
All the above
|
Om Desai answered |
Mitochondria are eukaryotic cell organelles. Mitochondria synthesize ATP through the process of aerobic respiration. Hence, mitochondria are called powerhouse of the cell. Carbohydrates are the most common fuel used to derive energy in aerobic respiration. When carbohydrates are in short supply, fats and proteins can also be used in aerobic respiration as reduced substrates. Thus, the correct answer is option D.
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