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All questions of Biological Molecules for A Level Exam
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Which is true about enzymes?a)All enzymes are proteins.b)All proteins are enzymes.c)All enzymes are not proteins.d)All enzymes are vitamins.Correct answer is option 'C'. Can you explain this answer?
|
Gaurav Kumar answered |
Enzymes are known to catalyze more than 5,000 biochemical reaction types. Most enzymes are proteins, although a few are catalytic RNA molecules. The latter are called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures.
Cellulose is made up of- a)Fructose
- b)Glucose
- c)Sucrose
- d)Ribose
Correct answer is option 'B'. Can you explain this answer?
Cellulose is made up of
a)
Fructose
b)
Glucose
c)
Sucrose
d)
Ribose
|
|
Ayush Chauhan answered |
Cellulose is a third polymer made from beta glucose molecules and the polymer molecules are straight cellulose serves a very different purpose in nature to starch and glycogen it make up the cell walls in plant cell.
The bacterial cell wall is formed of- a)Cellulose
- b)Hemicellulose
- c)Peptidoglycan
- d)Glycogen
Correct answer is option 'C'. Can you explain this answer?
The bacterial cell wall is formed of
a)
Cellulose
b)
Hemicellulose
c)
Peptidoglycan
d)
Glycogen
|
Pooja Shah answered |
Bacterial cell walls are made of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids. Bacterial cell walls are different from the cell walls of plants and fungi which are made of cellulose and chitin, respectively.
The number of amino acids found in proteins are- a)20
- b)21
- c)18
- d)16
Correct answer is option 'A'. Can you explain this answer?
The number of amino acids found in proteins are
a)
20
b)
21
c)
18
d)
16
|
Rohan Singh answered |
Proteinogenic amino acids are amino acids that are incorporated biosynthetically into proteins during translation. ... Throughout known life, there are 22 genetically encoded (proteinogenic) amino acids, 20 in the standard genetic code and an additional 2 that can be incorporated by special translation mechanisms.
The most abundant mineral of the animal body is- a)Potassium
- b)Sodium
- c)Calcium
- d)Iron
Correct answer is option 'C'. Can you explain this answer?
The most abundant mineral of the animal body is
a)
Potassium
b)
Sodium
c)
Calcium
d)
Iron
|
Hansa Sharma answered |
Calcium is the most abundant mineral in our body. It is essential for the development and maintenance of strong bones and teeth, where about 99% of the body's calcium is found. Calcium also helps the heart, nerves, muscles, and other body systems work properly.
Therefore, the correct answer is option C.
The most abundant organic molecule present on earth is- a)Protein
- b)Lipid
- c)Steroids
- d)Cellulose
Correct answer is option 'D'. Can you explain this answer?
The most abundant organic molecule present on earth is
a)
Protein
b)
Lipid
c)
Steroids
d)
Cellulose
|
Raghavendra Datta answered |
The most abundant organic molecule present on earth is cellulose.
What is Cellulose?
Cellulose is a complex carbohydrate that is found in the cell walls of plants. It is composed of repeating units of glucose molecules that are linked together to form long chains. These chains are then arranged in a way that gives cellulose its characteristic strength and rigidity.
Why is Cellulose Abundant on Earth?
Cellulose is abundant on earth for several reasons:
1. It is found in the cell walls of plants - Plants are the most abundant form of life on earth, and cellulose is a major component of their cell walls. This means that there is a huge amount of cellulose present on earth.
2. It is resistant to degradation - Unlike other organic molecules, cellulose is highly resistant to degradation by enzymes and other biological processes. This means that it can persist in the environment for a long time, contributing to its abundance.
3. It is a major component of biomass - Cellulose is a major component of the biomass of plants. When plants die and decompose, the cellulose in their cell walls is broken down into smaller molecules that can be used by other organisms. This means that there is a constant supply of cellulose being produced and broken down on earth.
Conclusion:
In conclusion, cellulose is the most abundant organic molecule present on earth due to its presence in the cell walls of plants, its resistance to degradation, and its role as a major component of biomass.
What is Cellulose?
Cellulose is a complex carbohydrate that is found in the cell walls of plants. It is composed of repeating units of glucose molecules that are linked together to form long chains. These chains are then arranged in a way that gives cellulose its characteristic strength and rigidity.
Why is Cellulose Abundant on Earth?
Cellulose is abundant on earth for several reasons:
1. It is found in the cell walls of plants - Plants are the most abundant form of life on earth, and cellulose is a major component of their cell walls. This means that there is a huge amount of cellulose present on earth.
2. It is resistant to degradation - Unlike other organic molecules, cellulose is highly resistant to degradation by enzymes and other biological processes. This means that it can persist in the environment for a long time, contributing to its abundance.
3. It is a major component of biomass - Cellulose is a major component of the biomass of plants. When plants die and decompose, the cellulose in their cell walls is broken down into smaller molecules that can be used by other organisms. This means that there is a constant supply of cellulose being produced and broken down on earth.
Conclusion:
In conclusion, cellulose is the most abundant organic molecule present on earth due to its presence in the cell walls of plants, its resistance to degradation, and its role as a major component of biomass.
Ester linkages occur in- a)Proteins
- b)Lipids
- c)Nucleic acids
- d)Carbohydrates
Correct answer is option 'B'. Can you explain this answer?
Ester linkages occur in
a)
Proteins
b)
Lipids
c)
Nucleic acids
d)
Carbohydrates
|
Anjali Iyer answered |
Lipids are actually triglycerides. A triglyceride consists of glycerol and fatty acids which are held together by ester linkages.
The oils have- a)High melting point
- b)Low melting point
- c)Optimum melting point
- d)No melting point
Correct answer is option 'B'. Can you explain this answer?
The oils have
a)
High melting point
b)
Low melting point
c)
Optimum melting point
d)
No melting point
|
|
Geetika Shah answered |
Oils have lower melting point (e.g., gingely oil) and hence remain as oil in winters.
An ester bond is present between- a)Amino acids
- b)Nucleoside
- c)Nucleotide
- d)Monosaccharides
Correct answer is option 'C'. Can you explain this answer?
An ester bond is present between
a)
Amino acids
b)
Nucleoside
c)
Nucleotide
d)
Monosaccharides
|
Syed Hussain answered |
Phosphodiester bond definition. A bondbetween a two sugar groups and a phosphate group; such bonds form the sugar-phosphate-sugar backbone of DNA and RNA. A diester bond (between phosphoric acid and two sugar molecules) linking two nucleotides together to form the nucleotide polymers DNA and RNA.
A homopolymer has only one type of building block called a monomer repeated ‘n’ number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers made of amino acids. While a nucleic acid like DNA or RNA is made of only 4 types of nucleotide monomers, proteins are made of- a)20 types of monomers
- b)3 types of monomers
- c)40 types of monomers
- d)Only one type of monomer
Correct answer is option 'A'. Can you explain this answer?
A homopolymer has only one type of building block called a monomer repeated ‘n’ number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers made of amino acids. While a nucleic acid like DNA or RNA is made of only 4 types of nucleotide monomers, proteins are made of
a)
20 types of monomers
b)
3 types of monomers
c)
40 types of monomers
d)
Only one type of monomer
|
Syed Hussain answered |
In living systems, like our own bodies, these larger molecules include carbohydrates, lipids, nucleic acids and proteins. The monomers of these organic groups are: Carbohydrates - monosaccharides. Lipids - glycerol and fatty acids
A nucleoside differs from a nucleotide in not having a- a)Phosphate group
- b)Glucose
- c)Sugar
- d)Nitrogen base
Correct answer is option 'A'. Can you explain this answer?
A nucleoside differs from a nucleotide in not having a
a)
Phosphate group
b)
Glucose
c)
Sugar
d)
Nitrogen base
|
Aliya Agrawal answered |
Phosphate group...
because nucleoside = sugar + nitrogen base...
while nucleotides = sugar + nitrogen base + phosphate group.....
because nucleoside = sugar + nitrogen base...
while nucleotides = sugar + nitrogen base + phosphate group.....
Double hydrogen bond occurs in DNA between- a)Adenine and guanine
- b)Thymine and cytosine
- c)Adenine and thymine
- d)Uracil and thymine
Correct answer is option 'C'. Can you explain this answer?
Double hydrogen bond occurs in DNA between
a)
Adenine and guanine
b)
Thymine and cytosine
c)
Adenine and thymine
d)
Uracil and thymine
|
|
Gaurav Kumar answered |
The complementary base pairs of guanine with cytosine and adenine with thymine connect to one another using hydrogen bonds. In addition to holding the DNA strands together, the hydrogen bonding between the complementary bases also sequester the bases in the interior of the double helix. Since, the option of Guanine and Cytosine is not provided. Hence, the correct option is Option C.
A segment of DNA has 120 adenine and 120 cytosine bases. The total number of nucleotides present in the segment is- a)480
- b)240
- c)60
- d)120
Correct answer is option 'A'. Can you explain this answer?
A segment of DNA has 120 adenine and 120 cytosine bases. The total number of nucleotides present in the segment is
a)
480
b)
240
c)
60
d)
120
|
|
Pooja Shah answered |
According to Chargaff’s rule, the amount of adenine is always equal to that of thymine and the amount of guanine is always equal to that of cytosine.
A = T(120), G = C(120)
The total number of nucleotides would be 120 × 4 = 480.
Which is a reducing sugar?- a)Cellulose
- b)Maltose
- c)Starch
- d)Sucrose
Correct answer is option 'B'. Can you explain this answer?
Which is a reducing sugar?
a)
Cellulose
b)
Maltose
c)
Starch
d)
Sucrose
|
|
Prem Darade answered |
The sugar that is capable of acting as a reducing sugar because it has free aldehyde group or a free ketone group ...
When we homogenise any tissue in an acid, the acid-soluble pool represents- a)Mitochondria
- b)Nucleus
- c)Cell membrane
- d)Cytoplasm
Correct answer is option 'D'. Can you explain this answer?
When we homogenise any tissue in an acid, the acid-soluble pool represents
a)
Mitochondria
b)
Nucleus
c)
Cell membrane
d)
Cytoplasm
|
|
Rohit Shah answered |
When we homogenise any tissue in an acid, the acid soluble pool represents cytoplasm.
The enzyme which cuts DNA is- a)DNA polymerase
- b)DNA ligase
- c)Restriction endonucleases
- d)DNA lyase
Correct answer is option 'C'. Can you explain this answer?
The enzyme which cuts DNA is
a)
DNA polymerase
b)
DNA ligase
c)
Restriction endonucleases
d)
DNA lyase
|
|
Baby Ghosh answered |
Restriction Endonucleases are enzyme which scan DNA molecules for a particular nucleotide sequence. These are called Recognition Sequences.Once the Endonuclease finds this sequence it halts ans cuts the strand.Thus,the correct option is "C".
Enzyme amylase belongs to- a)Hydrolases
- b)Transferases
- c)Isomerases
- d)Oxidoreductases
Correct answer is option 'A'. Can you explain this answer?
Enzyme amylase belongs to
a)
Hydrolases
b)
Transferases
c)
Isomerases
d)
Oxidoreductases
|
|
Ragini Shukla answered |
Hydrolase are the enzyme which breaks down the large molecules into smaller ones with the help of hydrogen and hydroxyl groups of water molecule this phenomena is known as hydrolysis. Amylase is the enzyme produced by the salivary gland and helps in breaking down the starch into glucose. Amylase catalysis the hydrolysis of starch into sugar (glucose).
Amylase is also found in germinating seeds.
Amylase is also found in germinating seeds.
The enzyme found functional in lysosome is- a)Acid phosphataseLyases
- b)Lyases
- c)Oxidoreductase
- d)Basic phosphatase
Correct answer is option 'B'. Can you explain this answer?
The enzyme found functional in lysosome is
a)
Acid phosphatase
Lyases
b)
Lyases
c)
Oxidoreductase
d)
Basic phosphatase
|
Vijay Bansal answered |
A lysosome is a membrane-bound organelle found in nearly all animal cells. They are spherical vesicles that contain hydrolytic enzymes that can break down many kinds of biomolecules.
The plant cell wall are made up of- a)Cellulose
- b)Starch
- c)Glycogen Bacteria
- d)Inulin
Correct answer is option 'A'. Can you explain this answer?
The plant cell wall are made up of
a)
Cellulose
b)
Starch
c)
Glycogen Bacteria
d)
Inulin
|
Srishti Sen answered |
Plant cell walls are made of cellulose. Paper made from plant pulp is cellulose.
DNA nucleotides are attached by
- a)Hydrogen bond
- b)Covalent bond
- c)Van der Waals bond
- d)Electrovalent bond
Correct answer is option 'A'. Can you explain this answer?
DNA nucleotides are attached by
a)
Hydrogen bond
b)
Covalent bond
c)
Van der Waals bond
d)
Electrovalent bond
|
|
Gopikas S answered |
Explanation: DNA nucleotides are attached by the Hydrogen bond. A nucleotide is the basic unit of polynucleotide chain of DNA (deoxyribonucleic acid) or RNA (Ribonucleic acid).
The nitrogenous bases are found in the strand's inward direction. The nitrogenous bases of the two antiparallel strands form hydrogen bonds, resulting in the formation of two helical strands.
The nitrogenous bases used in DNA (double-stranded helical structure) are adenine (A), cytosine (C), guanine (G), and thymine (T).
Adenine is joined to thymine with two hydrogen bonds, whereas guanine is joined to cytosine by three hydrogen bonds.
Thus, DNA nucleotides are attached by Hydrogen bond.
Enormous diversity of protein molecules is due to- a)R groups of amino acids
- b)Sequence of amino acids
- c)Peptide bonds
- d)Amino groups of amino acids
Correct answer is option 'B'. Can you explain this answer?
Enormous diversity of protein molecules is due to
a)
R groups of amino acids
b)
Sequence of amino acids
c)
Peptide bonds
d)
Amino groups of amino acids
|
|
Rajat Kapoor answered |
The third is tertiary; this is the folding of the secondary structures into the final 3D structure of a protein. Amino acids have properties that guide this; some interact easily with water (hydrophilic) and these orient themselves on the outside of a protein, while others don't interact well with water (hydrophobic) and will try to get themselves on the inside of the folded structure where they will be protected. Hydrophobicity/philicity is the major driving force in protein folding but other bonds will also be formed between amino acids like S-S linkages, other ionic bonds and HYDROGEN BONDS (tons of these are made). These smaller interactions generally stabilize the protein and keep it folded in the most ideal conformation possible.
Which of the following carbohydrates is not a disaccharide?- a)Lactose
- b)Maltose
- c)Sucrose
- d)Galactose
Correct answer is option 'D'. Can you explain this answer?
Which of the following carbohydrates is not a disaccharide?
a)
Lactose
b)
Maltose
c)
Sucrose
d)
Galactose
|
|
Gaurav Kumar answered |
Galactose is a monosaccharide. When combined with glucose (monosaccharide), through a condensation reaction, the result is the disaccharide lactose. The hydrolysis of lactose to glucose and galactose is catalyzed by the enzymes lactase and β-galactosidase.
Chemical formula: C6H12O6
Solubility in water: 650 g/L (20 °C)
Chemical formula: C6H12O6
Solubility in water: 650 g/L (20 °C)
The nucleotide chemical components are- a)Heterocyclic compounds, sugar and phosphate
- b)Sugar and Phosphate
- c)Heterocyclic compounds and sugar
- d)Phosphate and heterocyclic compounds
Correct answer is option 'A'. Can you explain this answer?
The nucleotide chemical components are
a)
Heterocyclic compounds, sugar and phosphate
b)
Sugar and Phosphate
c)
Heterocyclic compounds and sugar
d)
Phosphate and heterocyclic compounds
|
Akshat Chavan answered |
The nucleotide has three chemically distinct components. One is a heterocyclic compound, the second is a monosaccharide and the third a phosphoric acid or phosphate.
Which enzyme is concerned with the transfer of electrons?
- a)Dehydrogenase
- b)Transaminase
- c)Hydrolase
- d) Desmolase
Correct answer is option 'A'. Can you explain this answer?
Which enzyme is concerned with the transfer of electrons?
a)
Dehydrogenase
b)
Transaminase
c)
Hydrolase
d)
Desmolase
|
|
Leelu Bhai answered |
Transaminase are the enzymes concerned with transfer of atoms or group of atoms or electrons.. so, option B is correct not A
Proteins perform many physiological functions. For example, some function as enzymes. Which one of the following represents an additional function which some proteins discharge?- a)Antibiotics
- b)Pigments making colours of flowers
- c)Hormones
- d)Pigments conferring colour to skin
Correct answer is option 'C'. Can you explain this answer?
Proteins perform many physiological functions. For example, some function as enzymes. Which one of the following represents an additional function which some proteins discharge?
a)
Antibiotics
b)
Pigments making colours of flowers
c)
Hormones
d)
Pigments conferring colour to skin
|
|
Anjali Iyer answered |
Proteins perform many physiological functions. For example, some proteins function as enzymes. Hormones represents an additional function that some proteins discharge (like insulin).
Fehling’s solution is used for the detection of- a)Fats
- b)Starch
- c)Glucose
- d)All carbohydrates
Correct answer is option 'C'. Can you explain this answer?
Fehling’s solution is used for the detection of
a)
Fats
b)
Starch
c)
Glucose
d)
All carbohydrates
|
Athira Mukherjee answered |
Fehling is a chemical reagent used to test for the presence of aldehyde functional groups. It consists of two separate solutions, Fehling's A and Fehling's B, which are mixed together before use. When an aldehyde is added to Fehling's solution and heated, a red precipitate of copper(I) oxide is formed, indicating the presence of the aldehyde. Fehling's reagent is commonly used in organic chemistry laboratories to identify and distinguish aldehydes from other types of compounds.
Which is the most abundant chemical for the living organisms?- a)Lipids
- b)Proteins
- c)Ions
- d)Water
Correct answer is option 'D'. Can you explain this answer?
Which is the most abundant chemical for the living organisms?
a)
Lipids
b)
Proteins
c)
Ions
d)
Water
|
Anand Jain answered |
Water is the most abundant chemical for the living organisms.
DNA differs from RNA in having- a)Thymine but no uracil
- b)Uracil but no thymine
- c)Thymine but no cytosine
- d)Cytosine but no guanine
Correct answer is option 'A'. Can you explain this answer?
DNA differs from RNA in having
a)
Thymine but no uracil
b)
Uracil but no thymine
c)
Thymine but no cytosine
d)
Cytosine but no guanine
|
Om Desai answered |
Uracil is energetically less expensive to produce than thymine, which may account for its use in RNA. In DNA, however, uracil is readily produced by chemical degradation of cytosine, so having thymine as the normal base makes detection and repair of such incipient mutations more efficient.
Which of the following is not a conjugated protein?- a)Peptone
- b)Glycoprotein
- c)Chromoprotein
- d)Lipoprotein
Correct answer is option 'A'. Can you explain this answer?
Which of the following is not a conjugated protein?
a)
Peptone
b)
Glycoprotein
c)
Chromoprotein
d)
Lipoprotein
|
Nandini Patel answered |
A conjugated protein is a protein that functions in interaction with other (non-polypeptide) chemical groups attached by covalent bonding or weak interactions. Many proteins contain only amino acids and no other chemical groups, and they are called simple proteins.
In yeast, during fermentation the glycolysis pathway leads to- a)Production of glucose
- b)Production of oxygen
- c)Production of pyruvic acid
- d)Production of ethanol
Correct answer is option 'D'. Can you explain this answer?
In yeast, during fermentation the glycolysis pathway leads to
a)
Production of glucose
b)
Production of oxygen
c)
Production of pyruvic acid
d)
Production of ethanol
|
Jatin Chakraborty answered |
In yeast, during fermentation, the same pathway leads to the production of ethanol(alcohol).
Which of the following is not obtained on hydrolysis of nucleic acid?- a)Purine
- b)Phosphoric acid
- c)Pyrimidine
- d)Pentose sugar
Correct answer is option 'B'. Can you explain this answer?
Which of the following is not obtained on hydrolysis of nucleic acid?
a)
Purine
b)
Phosphoric acid
c)
Pyrimidine
d)
Pentose sugar
|
Ruchi Chopra answered |
Hydrolysis of nucleic acid (DNA and RNA) produces pentose sugar (ribose or deoxyribose) purine and pyrimidine. Phosphoric acid is not released on hydrolysis of DNA or RNA.
The energy currency of cell is—- a)GDP
- b)ATP
- c)ADP
- d)NAD
Correct answer is option 'B'. Can you explain this answer?
The energy currency of cell is—
a)
GDP
b)
ATP
c)
ADP
d)
NAD
|
|
Rohan Singh answered |
When the ATP converts to ADP, the ATP is said to be spent. he molecule is used like a battery within cells and allows the consumption of one of its phosphorous molecules.The energy currency used by all cells from bacteria to man is adenosine triphosphate (ATP).
Which one is not a denaturing factor for protein?- a)High energy radiation
- b)High pressure
- c)Drastic change in pH
- d)High temperature
Correct answer is option 'B'. Can you explain this answer?
Which one is not a denaturing factor for protein?
a)
High energy radiation
b)
High pressure
c)
Drastic change in pH
d)
High temperature
|
Prasenjit Pillai answered |
Protein molecules get denatured due to high temperature, very high or low pH and high energy radiation but there is no effect due to high pressure.
A peptide bond is formed by the process of- a)Amination
- b)Rehydration
- c)Deamination
- d)Dehydration
Correct answer is option 'D'. Can you explain this answer?
A peptide bond is formed by the process of
a)
Amination
b)
Rehydration
c)
Deamination
d)
Dehydration
|
|
Preeti Iyer answered |
A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O). This is a dehydration synthesis reaction (also known as a condensation reaction), and usually occurs between amino acids.
In a DNA molecule, two strands are held by- a)Nitrogen bonds
- b)Phosphate bonds
- c)Carbon bonds
- d)Hydrogen bonds
Correct answer is option 'D'. Can you explain this answer?
In a DNA molecule, two strands are held by
a)
Nitrogen bonds
b)
Phosphate bonds
c)
Carbon bonds
d)
Hydrogen bonds
|
|
Pooja Mehta answered |
By hydrogen bonds between the two bases. Basically, the bases are ‘polar’, meaning they have slight differences in electrical charge at certain points. This allows them to attract one another like a balloon sticking to your hair.
Hydrogen bonds are weaker than the covalent bonds that hold the rest of the molecule together, making them easier to break and re-form.
A polysaccharide present as storehouse of energy of plant tissues- a)Chitin
- b)Starch
- c)Hemi cellulose
- d)Cellulose
Correct answer is option 'B'. Can you explain this answer?
A polysaccharide present as storehouse of energy of plant tissues
a)
Chitin
b)
Starch
c)
Hemi cellulose
d)
Cellulose
|
Jyoti Kapoor answered |
Polysaccharide
A polysaccharide is a large molecule made of many smaller monosaccharides. Monosaccharides are simple sugars, like glucose. Special enzymes bind these small monomers together creating large sugar polymers, or polysaccharides. A polysaccharide is also called a glycan. A polysaccharide can be a homopolysaccharide, in which all the monosaccharides are the same, or a heteropolysaccharide in which the monosaccharides vary. Depending on which monosaccharides are connected, and which carbons in the monosaccharides connects, polysaccharides take on a variety of forms. A molecule with a straight chain of monosaccharides is called a linear polysaccharide, while a chain that has arms and turns is known as a branched polysaccharide.
. __________ is a globular protein of 6 kDa consisting of 51 amino acids arranged in 2 polypeptide chains held together by a disulphide bridge- a)Fibrinogen
- b)Keratin
- c)Insulin
- d)Glucagon
Correct answer is option 'C'. Can you explain this answer?
. __________ is a globular protein of 6 kDa consisting of 51 amino acids arranged in 2 polypeptide chains held together by a disulphide bridge
a)
Fibrinogen
b)
Keratin
c)
Insulin
d)
Glucagon
|
|
Pooja Mehta answered |
Human insulin is a peptide hormone composed of 51 ammo acids and has a molecular weight of 5805 Da.(∼6 Kda). In this molecule, there are two polypeptide chains (A and B) held together by disulphide bridge.
One turn of the DNA double helix spans a distance of- a)3.4 nm
- b)4.26 nm
- c)4.56 nm
- d)2.46 nm
Correct answer is option 'A'. Can you explain this answer?
One turn of the DNA double helix spans a distance of
a)
3.4 nm
b)
4.26 nm
c)
4.56 nm
d)
2.46 nm
|
|
Suresh Kumar answered |
Refer biomolecules chapter in Ncert .Its mentioned in that chapter...
Which one of the following pairs of nitrogenous bases of nucleic acids is wrongly matched with the category mentioned against it?- a)Adenine, Thymine – Purines
- b)Uracil, Cytosine – Pyrimidines
- c)Guanine, Adenine – Purines
- d)Thymine, Uracil – Pyrimidines
Correct answer is option 'A'. Can you explain this answer?
Which one of the following pairs of nitrogenous bases of nucleic acids is wrongly matched with the category mentioned against it?
a)
Adenine, Thymine – Purines
b)
Uracil, Cytosine – Pyrimidines
c)
Guanine, Adenine – Purines
d)
Thymine, Uracil – Pyrimidines
|
Aastha Kulshreshtha answered |
Answer= a
As,
•purines= Adenine and Guanine.
•pyrimidine= Cytosine, Uracil and Thymine.
therefore the wrongly matched pair would be A.
As,
•purines= Adenine and Guanine.
•pyrimidine= Cytosine, Uracil and Thymine.
therefore the wrongly matched pair would be A.
An immediate source of cellular energy is- a)Pyruvic acid
- b)NADH
- c)Glucose
- d)ATP
Correct answer is option 'D'. Can you explain this answer?
An immediate source of cellular energy is
a)
Pyruvic acid
b)
NADH
c)
Glucose
d)
ATP
|
|
Supriya Senapati answered |
Because during cellular respiration, Glucose undergoes oxidation through various enzymatic machinery to produce energy which is stored as the ATP( energy currency of cell ) , ATP is further utilized by the different cell for their activities.
Which one of the following is fibrous protein?- a)Collagen
- b)Ribozymes
- c)Haemoglobin
- d)Hemicellulose
Correct answer is option 'A'. Can you explain this answer?
Which one of the following is fibrous protein?
a)
Collagen
b)
Ribozymes
c)
Haemoglobin
d)
Hemicellulose
|
Shanaya Rane answered |
Collagen is a fibrous protein. It is the main structural protein in the extracellular space in thevarious connective tissues. It is the most abundant protein in mammals.
The part of enzyme bound to the protein part by a covalent bond is called- a)Holoenzyme
- b)Cofactor
- c)Prosthetic group
- d)Apoenzyme
Correct answer is option 'C'. Can you explain this answer?
The part of enzyme bound to the protein part by a covalent bond is called
a)
Holoenzyme
b)
Cofactor
c)
Prosthetic group
d)
Apoenzyme
|
Palak Sharma answered |
According to ncert the part which is attach with protein part with covalent bond is metal ion which is a cofactor
An organic substance bound to an enzyme and essential for its activity is called- a)Isoenzyme
- b)Coenzyme
- c)Holoenzyme
- d)Apoenzyme
Correct answer is option 'B'. Can you explain this answer?
An organic substance bound to an enzyme and essential for its activity is called
a)
Isoenzyme
b)
Coenzyme
c)
Holoenzyme
d)
Apoenzyme
|
|
Rohan Singh answered |
Coenzyme is an organic nonprotein molecule that associates with an enzyme molecule in catalsying biochemical reactions. It usually participates in the substrate-enzyme interaction by donating or accepting certain chemical groups. Holoenzyme is a complex comprising of enzyme molecule and its cofactor. The enzyme is catalytically active in this state. Apoenzyme is an inactive enzyme that must associate with a specific cofactor molecule in order to function. Isoenzyme or isozyme is one of the several forms of an enzyme that catalyse the same reaction but differ from each other in such properties as substrate affinity and maximum rates of enzyme-substrate reaction.
Which of the following nitrogenous base produces nucleoside only with ribose sugar?- a)Thymine
- b)Guanine
- c)Uracil
- d)Adenine
Correct answer is option 'C'. Can you explain this answer?
Which of the following nitrogenous base produces nucleoside only with ribose sugar?
a)
Thymine
b)
Guanine
c)
Uracil
d)
Adenine
|
Ruchi Chakraborty answered |
Uracil nitrogenous base is produces nucleoside only with ribose sugar. This nucleoside is present only inside the RNA and absent in DNA.
Lipids that are found in the cell membrane are- a)Triglycerides
- b)Simple lipids
- c)Diglycerides
- d)Phospholipids
Correct answer is option 'D'. Can you explain this answer?
Lipids that are found in the cell membrane are
a)
Triglycerides
b)
Simple lipids
c)
Diglycerides
d)
Phospholipids
|
Aniket Chawla answered |
Some lipids have phosphorous and a phosphorylated organic compound in them. These are phospholipids. They are found in cell membrane.
The amino acids are linked together serially by- a)Peptide bonds
- b)Hydrogen bonds
- c)Covalent bonds
- d)Ionic bonds
Correct answer is option 'A'. Can you explain this answer?
The amino acids are linked together serially by
a)
Peptide bonds
b)
Hydrogen bonds
c)
Covalent bonds
d)
Ionic bonds
|
Prashanth Dasgupta answered |
The amino acids are linked together one after the other by peptide bonds. This bond is formed between NH3 of one amino acids with carboxyl end of another amino acids to release water.
Enzymes with slightly different molecular structure but performing identical activity are- a)Isoenzymes
- b)Apoenzymes
- c)Holoenzyme
- d)Coenzymes
Correct answer is option 'A'. Can you explain this answer?
Enzymes with slightly different molecular structure but performing identical activity are
a)
Isoenzymes
b)
Apoenzymes
c)
Holoenzyme
d)
Coenzymes
|
|
Mira Tiwari answered |
Enzymes with slightly different molecular structure but performing identical activity are called isoenzymes.
Explanation:
Enzymes are biological catalysts that facilitate and speed up biochemical reactions in living organisms. They are usually proteins with a specific three-dimensional structure that allows them to bind to specific substrates and convert them into products. However, enzymes can also have slightly different molecular structures while performing the same catalytic activity. These enzymes are called isoenzymes.
Definition of Isoenzymes:
Isoenzymes, also known as isozymes, are enzymes that catalyze the same chemical reaction but have slightly different amino acid sequences or molecular structures. They are encoded by different genes but perform identical functions in the same organism or different tissues. Isoenzymes are often found in multiple forms and can be distinguished from each other through various methods such as electrophoresis or immunoassay.
Reasons for Different Molecular Structures:
1. Genetic Differences: Isoenzymes are encoded by different genes, which can result in variations in the amino acid sequence and overall structure of the enzyme.
2. Post-translational Modifications: Isoenzymes may undergo different post-translational modifications, such as phosphorylation or glycosylation, which can alter their structure and function.
3. Tissue-Specific Expression: Different tissues within an organism may require slightly different versions of an enzyme to perform the same activity optimally. These tissue-specific isoenzymes may have distinct molecular structures.
Importance of Isoenzymes:
1. Diagnostic Tool: Isoenzymes can be used as diagnostic markers for certain diseases or conditions. For example, the measurement of different forms of creatine kinase isoenzymes can help diagnose heart attacks.
2. Tissue-Specific Function: Isoenzymes may have different kinetic properties or substrate specificities, allowing them to perform specialized functions in specific tissues.
3. Evolutionary Adaptation: Isoenzymes can evolve to perform similar functions under different conditions or in different organisms, allowing for adaptation and survival in diverse environments.
In conclusion, isoenzymes refer to enzymes with slightly different molecular structures but identical catalytic activities. They play important roles in various biological processes and have diagnostic and evolutionary significance.
Explanation:
Enzymes are biological catalysts that facilitate and speed up biochemical reactions in living organisms. They are usually proteins with a specific three-dimensional structure that allows them to bind to specific substrates and convert them into products. However, enzymes can also have slightly different molecular structures while performing the same catalytic activity. These enzymes are called isoenzymes.
Definition of Isoenzymes:
Isoenzymes, also known as isozymes, are enzymes that catalyze the same chemical reaction but have slightly different amino acid sequences or molecular structures. They are encoded by different genes but perform identical functions in the same organism or different tissues. Isoenzymes are often found in multiple forms and can be distinguished from each other through various methods such as electrophoresis or immunoassay.
Reasons for Different Molecular Structures:
1. Genetic Differences: Isoenzymes are encoded by different genes, which can result in variations in the amino acid sequence and overall structure of the enzyme.
2. Post-translational Modifications: Isoenzymes may undergo different post-translational modifications, such as phosphorylation or glycosylation, which can alter their structure and function.
3. Tissue-Specific Expression: Different tissues within an organism may require slightly different versions of an enzyme to perform the same activity optimally. These tissue-specific isoenzymes may have distinct molecular structures.
Importance of Isoenzymes:
1. Diagnostic Tool: Isoenzymes can be used as diagnostic markers for certain diseases or conditions. For example, the measurement of different forms of creatine kinase isoenzymes can help diagnose heart attacks.
2. Tissue-Specific Function: Isoenzymes may have different kinetic properties or substrate specificities, allowing them to perform specialized functions in specific tissues.
3. Evolutionary Adaptation: Isoenzymes can evolve to perform similar functions under different conditions or in different organisms, allowing for adaptation and survival in diverse environments.
In conclusion, isoenzymes refer to enzymes with slightly different molecular structures but identical catalytic activities. They play important roles in various biological processes and have diagnostic and evolutionary significance.
Metal ions required for functioning of enzyme is- a)Holoenzyme
- b)Co-enzyme
- c)Prosthetic group
- d)Co-factor
Correct answer is option 'D'. Can you explain this answer?
Metal ions required for functioning of enzyme is
a)
Holoenzyme
b)
Co-enzyme
c)
Prosthetic group
d)
Co-factor
|
Prerna Chauhan answered |
Co-factor: Metal ions required for functioning of enzyme
Metal ions play a crucial role in the functioning of enzymes by serving as essential co-factors. These metal ions are required for the enzyme to catalyze specific reactions efficiently.
In the context of metal ions as co-factors, they are necessary for the proper functioning of many enzymes. Without these metal ions, the enzyme may not be able to perform its catalytic function effectively. Therefore, metal ions are crucial for the activity of certain enzymes and are classified as co-factors in enzyme catalysis.
Metal ions play a crucial role in the functioning of enzymes by serving as essential co-factors. These metal ions are required for the enzyme to catalyze specific reactions efficiently.
- Holoenzyme: The complete, catalytically active form of an enzyme is known as a holoenzyme. It consists of both the protein component (apoenzyme) and the necessary co-factor, such as a metal ion.
- Co-enzyme: While co-enzymes are organic molecules that assist enzymes in their function, metal ions specifically serve as inorganic co-factors. They help in stabilizing the enzyme's structure and facilitating the catalytic reaction.
- Prosthetic group: Metal ions can also be tightly bound to the enzyme as a prosthetic group, essential for its activity. These ions are not easily dissociated from the enzyme during its catalytic cycle.
In the context of metal ions as co-factors, they are necessary for the proper functioning of many enzymes. Without these metal ions, the enzyme may not be able to perform its catalytic function effectively. Therefore, metal ions are crucial for the activity of certain enzymes and are classified as co-factors in enzyme catalysis.
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