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

Which of the following statements is/are true about spheroproteins?

P. Spheroproteins form adducts in water, unlike fibrous or membrane proteins. Q. The spherical structure is induced by the protein's tertiary structure. R. Globular proteins have a mechanism for protein folding, which is nucleation condensation model.

  1. Only P

  2. Only Q

  3. Only R

  4. Only P and Q

  5. Only P and R
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This option is correct because spherical structure is induced by the protein's tertiary structure.

Multiple choice

Which of the following statements is/are incorrect about acute-phase proteins?

A. The liver responds by producing a large number of acute-phase proteins. B. Positive acute-phase proteins serve similar physiological functions for the immune system. C. Negative acute-phase proteins decrease inflammation.

  1. Only A

  2. Only B

  3. Only C

  4. Only A and B

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

This option is correct. Positive acute-phase proteins serve different physiological functions for the immune system.

Multiple choice

NPK stands for

  1. nitrogen, protein, kinetic

  2. nitrogen, protein, potassium

  3. nitrogen, phosphorus, potassium

  4. nitrogen, phosphorus, kinetin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

NPK stands for Nitrogen (N), Phosphorous (P) and Potassium (K). 

Multiple choice

Phosphorus is a structural element in

  1. proteins

  2. carbohydrates

  3. DNA

  4. cytochrome
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Phosphorus is a fundamental component of the sugar-phosphate backbone in DNA and RNA. It is also found in ATP and phospholipids, but it is not a structural part of simple proteins or carbohydrates.

Multiple choice

Which one of the following is a protein?

  1. Ppsin

  2. Carotene

  3. Keratin

  4. Progesterone
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Keratin is a fibrous structural protein that makes up the outer layer of human skin, hair, and nails. Carotene is a pigment, progesterone is a steroid hormone, and "Ppsin" appears to be a typo for pepsin (which is also an enzyme/protein, but misspelled here).

Multiple choice

The protein part of an enzyme is called

  1. apoenzyme

  2. prosthetic group

  3. coenzyme

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

An apoenzyme is the protein component of an enzyme that is inactive until combined with a cofactor or coenzyme.

Multiple choice

Milk contains the protein:

  1. casein

  2. globulin

  3. albumin

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

Casein is the primary protein found in milk, accounting for about 80 percent of the total protein content.

Multiple choice

Serum albumin in human blood is:

  1. simple protein

  2. complex protein

  3. conjugated protein

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

Serum albumin is a simple protein because it consists only of amino acids without any non-protein prosthetic groups. Conjugated proteins require a non-protein component.

Multiple choice

Which of the following is a pair of zinc containing enzymes?

  1. Carboxypeptidase and ATPase

  2. Carbonic anhydrase and Phosphoglucomutase

  3. Carbonic anhydrase and Carboxypeptidase

  4. ATPase and Phosphoglucomutase

  5. Phosphoglucomutase and Carboxypeptidase
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Carboxypeptidase and carbonic anhydrase are zinc containing enzymes.

Multiple choice

Which of the following statements are false?

  1. All transferrins are lipoproteins.
  2. The transport of iron from storage sites in cellular ferritin or hemosiderin occurs via the serum-transport protein transferrin.
  3. Each transferrin binds only one iron atom.
  4. The protein coat of ferritin is a hollow sphere of 24 polypeptide chains.

Select the correct answer using codes given below:

  1. 1 and 2

  2. 1 and 3

  3. 1 and 4

  4. 2 and 3

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

All transferrins are glycoproteins. Although transferrins have a high molecular weight, they bind only two iron atoms.