Biology · Chemistry

Biomolecules and Enzymes

1,432 Questions

This topic focuses on biomolecules, specifically proteins, enzymes, and amino acids. It includes questions on enzyme structures, protein folding, and catalysis. These concepts are crucial for medical and biology competitive exams.

Enzyme catalysisProtein structuresAmino acid synthesisPolypeptide chainsBiomolecule properties

Biomolecules and Enzymes Questions

Multiple choice

The most abundant protein in the human body is ____.

  1. collagen

  2. haemoglobin

  3. keratin

  4. myoglobin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Collagen is the most abundant protein in the human body, making up about 30% of total protein content. It provides structural support to connective tissues like skin, bones, tendons, and ligaments. Haemoglobin is found only in red blood cells, keratin in hair and nails, and myoglobin in muscles.

Multiple choice

Which of the following statements is correct regarding enzymes?

  1. Induced fit theory of enzymes was given by Emil Fischer.

  2. Michaelis constant is the substrate concentration at which enzyme reaction proceeds at half the maximum velocity.

  3. Synthesis of enzymes is directed by tRNA.

  4. Enzymes exist in cells as solids.

  5. Zymogen is an enzyme.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Michaelis constant is the substrate concentration at which the reaction velocity is 50% of the Vmax.

Multiple choice

What is the full form of “GFP”?

  1. Green Fluorescent Protein

  2. Glow Fluorescent Protein

  3. Green Fibre Protein

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

GFP is Green Fluorescent Protein, a protein that exhibits green fluorescence when exposed to blue light。'Glow'和'Fibre'是不正确的科学术语扩展。

Multiple choice

Alpha Keratin is a protein present in

  1. skin

  2. eggs

  3. blood

  4. wool
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Alpha-keratin is a fibrous structural protein found in hard keratinized tissues like wool, hair, nails, horns, and the outer layer of skin. It is not present in eggs, blood, or as the primary component of skin.

Multiple choice

Transport proteins _______________.

  1. are invariably integral proteins

  2. are sometimes called permeases

  3. are highly specific often for a single compound or small groups of closely related compounds

  4. are often globular proteins

  5. all of the above
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

All the statements given above are correct.

Multiple choice

The cytoskeletal protein of microtubules is

  1. tubulin

  2. tubulin and actin

  3. actin and ankyrin

  4. myosin

  5. tropomyosin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Tubulin heterodimer is the structural subunit of microtubules, which are cytoskeletal elements that are essential for intracellular transport and cell division.

Multiple choice

Which of the following statements are FALSE?

  1. Synteny refers to local conservation of gene order.
  2. The helix content of a protein can be determined using circular dichromism spectroscopy.
  3. In zinc finger proteins, the amino acid residues that coordinate zinc are Cys and Met.
  4. The production of secondary metabolites in plant cell cultures is enhanced by the addition of elicitors.

  1. Only 1 and 2

  2. Only 1 and 3

  3. Only 2 and 3

  4. Only 2 and 4

  5. Only 3 and 4
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Yes, this is the correct answer, as both the statements are false. Synteny refers to gene duplication from a common ancestor. This is the condition in which two or more gene loci are present on the same chromosome. During evolution, rearrangements may cause the loss of synteny, or else it will be retained. Translocations can cause gain of synteny. In zinc finger proteins, the amino acid residues that coordinate zinc are Cys and His. Zinc fingers coordinate zinc ions with a combination of cysteine and histidine residues. They can be classified by the type and order of these zinc coordinating residues (e.g., Cys2His2, Cys4, and Cys6).

Multiple choice

Which of the following is/are essential amino acid(s)?

  1. Alanine and glycine

  2. Cysteine

  3. Leucine and isoleucine

  4. Proline and serine

  5. Asparagine and glutamine
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

These are essential amino acids. These are simple amino acids. These are non-essential acidamide amino acids.