Explore topic-wise MCQs in Biochemistry.

This section includes 59 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following presents antigenic peptide to T-cells in order to initiate an adaptive immune response?

A. Plasma cell
B. Dendrite cell
C. Neutrophil
D. Epithelial cell
Answer» B. Dendrite cell
2.

Which of the following bonds are not involved in tertiary type of protein structure?

A. Disulfide bond
B. Hydrogen bonding
C. Salt bridges
D. Hydrophilic interactions
Answer» E.
3.

Which of the following is a function of Macrophages?

A. Ingest large particles and cells by phagocytes
B. Produce and secrete antibodies
C. Interact with infected host cells through receptors on T-cell surface
D. Interact with macrophages and secrete cytokines
Answer» B. Produce and secrete antibodies
4.

Which of the following is a function of B lymphocytes?

A. Ingest large particles and cells by phagocytes
B. Produce and secrete antibodies
C. Interact with infected host cells through receptors on T-cell surface
D. Interact with macrophages and secrete cytokines
Answer» C. Interact with infected host cells through receptors on T-cell surface
5.

In the binding of oxygen to myoglobin, the relationship between the concentration of oxygen and the fraction of binding sites occupied can best be described as ___________

A. Hyperbolic
B. Linear with a negative slope
C. Linear with a positive slope
D. Parabolic
Answer» B. Linear with a negative slope
6.

Myoglobin binding of O₂ depends on ___________

A. Hemoglobin concentration
B. O₂ concentration and affinity of myoglobin for O₂
C. Ka
D. Kd
Answer» C. Ka
7.

IgG consists of ____________

A. A light chain and two heavy chains joined by a disulfide bond
B. Two light chains and a heavy chain joined by a disulfide bond
C. Two light chains and two heavy chains joined by a disulfide bond
D. Two light chains and two heavy chains joined by hydrogen bond
Answer» D. Two light chains and two heavy chains joined by hydrogen bond
8.

Process of folding does not depend on ____________

A. Concentration of salts
B. pH
C. Solute
D. Solvent
Answer» D. Solvent
9.

Which of the following is a function of chaperone protein?

A. It degrades proteins that have folded improperly
B. It provide a template for how the proteins should fold
C. It rescues proteins that have folded improperly and allows them to refold properly
D. It degrades proteins that have folded properly
Answer» D. It degrades proteins that have folded properly
10.

Fibroin is rich in ________

A. Alanine and Glycine
B. Alanine
C. Glycine
D. Pro
Answer» B. Alanine
11.

Which of the following are chaperons in E.coli?

A. Hsp70
B. Hsp40
C. DnaA
D. DnaK and DnaJ
Answer» E.
12.

Which of the following is a component of mitochondria?

A. Ribonuclease
B. Lysozyme
C. Cytochrome c
D. Myoglobin
Answer» D. Myoglobin
13.

Which of the following cannot denature a protein?

A. Iodoacetic acid
B. SDS detergent
C. Urea
D. Heating to 90°C
Answer» B. SDS detergent
14.

Which of the following contractile protein of skeletal muscle involve in ATPase activity?

A. Troponin
B. Myosin
C. Tubulin
D. Tropomyosin
Answer» C. Tubulin
15.

Which of the following serves as bactericidal agent?

A. Ribonuclease
B. Lysozyme
C. Cytochrome c
D. Myoglobin
Answer» C. Cytochrome c
16.

Which of the following forces is favorable for protein folding?

A. Hydrophobic interactions
B. Hydrogen bonding
C. Vander Waals forces
D. Ionic bonding
Answer» B. Hydrogen bonding
17.

The cross bridges involved in muscle contraction are located on the __________

A. Myosin myofilaments
B. Actin myofilaments
C. Tropomyosin
D. Dystrophin
Answer» B. Actin myofilaments
18.

Protein A will fold into its native state only when protein B is also present in the solution. However, protein B can fold itself into native confirmation without the presence of protein A. Which of the following is true?

A. Protein B serves as precursor for protein A
B. Protein B serves as molecular chaperon for protein A
C. Protein B serves as ligand for protein A
D. Protein B serves as structural motif for protein A
Answer» C. Protein B serves as ligand for protein A
19.

Which of the following enzyme is secreted by the pancreas?

A. Ribonuclease
B. Lysozyme
C. Cytochrome c
D. Myoglobin
Answer» B. Lysozyme
20.

The most abundant immunoglobulin is ____________

A. IgA
B. IgE
C. IgG
D. IgM
Answer» D. IgM
21.

Which of the following is abundantly found in collagen?

A. Glycine
B. Serine
C. Alanine
D. Tryptophan
Answer» B. Serine
22.

Which of the following is false about fibrous protein?

A. It is in rod or wire like shape
B. Keratin and collagen are the best examples
C. Hemoglobin is the best example
D. It provides structural support for cells and tissues
Answer» D. It provides structural support for cells and tissues
23.

Which of the following is not the function of helper T cells is ____________

A. Produce soluble signaling proteins called cytokines, which include the interleukins
B. They help activate cytotoxic T cells to kill infected target cells
C. They help activate B cells to secrete antibodies and macrophages to destroy ingested microbes
D. They recognize and bind extracellular ligands
Answer» E.
24.

The primary antibody of exocrine secretions is ____________

A. IgA
B. IgE
C. IgG
D. IgM
Answer» B. IgE
25.

His⁹³ is also called ________

A. His F8
B. His F7
C. His F6
D. His F5
Answer» B. His F7
26.

Which of the following is not a feature of secondary immune respone to an antigen when compared to the first immune response to the same antigen?

A. Antibody is generated without T-cell help
B. Antibody is generated fast
C. Antibody produced has greater affinity for the antigen
D. Much antibody is produced
Answer» B. Antibody is generated fast
27.

Which of the following about spontaneous folding is false?

A. It involves the initial formation of highly compact structure
B. It involves initial formation of a local secondary structure
C. It is essentially a random process
D. It may be defective in some human diseases
Answer» D. It may be defective in some human diseases
28.

Myoglobin and the subunits of hemoglobin have ___________

A. Very different primary and tertiary structures
B. Very similar primary and tertiary structures
C. Very similar primary structures, but different tertiary structures
D. Very similar tertiary structures, but different primary structures
Answer» E.
29.

Which of the following does not possess a quaternary structure?

A. Myoglobin
B. Lactate dehydrogenase
C. Immunoglobin M
D. Creatine Phospho Kinase
Answer» B. Lactate dehydrogenase
30.

Contractile protein of a muscle is __________

A. Troponin
B. Myosin
C. Tubulin
D. Tropomyosin
Answer» C. Tubulin
31.

Light band has which of the following filament protein?

A. Actin
B. Myosin
C. Actin and myosin
D. Tubulin
Answer» B. Myosin
32.

Which of the following is a correct relation?

A. Ka [L] = [PL] ⁄ [P]
B. Ka [L] = [P] ⁄ [PL]
C. Ka [L] = [PL] × [P]
D. Ka [PL] = [L] ⁄ [P]
Answer» B. Ka [L] = [P] ⁄ [PL]
33.

As folding progresses which of the following does not take place?

A. Entropy decreases
B. Amount of protein in native state increases
C. Free energy increases
D. Amount of protein in native state decreases
Answer» E.
34.

Which of the following is first determined as oligomer?

A. Myoglobin
B. Collagen
C. Keratin
D. Hemoglobin
Answer» E.
35.

Which of the following is a function of T lymphocytes?

A. Ingest large particles and cells by phagocytes
B. Produce and secrete antibodies
C. Interact with infected host cells through receptors on T-cell surface
D. Interact with macrophages and secrete cytokines
Answer» D. Interact with macrophages and secrete cytokines
36.

Which of the following is true about ribonucease?

A. Native state which is catalytically inactive is denatured
B. Unfolded state is inactive
C. Renatured ribonuclease is inactive
D. Renaturation involves reestablishment of the correct disulfide cross links
Answer» B. Unfolded state is inactive
37.

A process by which a protein structure assumes its functional shape or conformation is?

A. Denaturing
B. Folding
C. Synthesis
D. Hydrolysis
Answer» C. Synthesis
38.

Myoglobin is particularly abundant in ________

A. Nerves
B. Muscles
C. Blood cells
D. Skin
Answer» C. Blood cells
39.

The contractile unit consisting of bundles of thick filaments interleaved at either end with those of thin filaments is?

A. Myofibril
B. Cross bridges
C. Z band
D. Sarcomere
Answer» E.
40.

When oxygen binds to a heme-containing protein, the two open coordination bonds of Fe²⁺ are occupied by___________

A. One O atom and one amino acid atom
B. One O₂ molecule and one amino acid atom
C. One O₂ molecule and one heme atom
D. Two O atoms
Answer» C. One O₂ molecule and one heme atom
41.

The interactions of ligands with proteins are ___________

A. Relatively nonspecific
B. Relatively rare in biological systems
C. Usually irreversible
D. Usually transient
Answer» E.
42.

Which of the following is the smallest division?

A. Actin
B. Fiber
C. Fibril
D. Filament
Answer» B. Fiber
43.

Sarcomere is a part between __________

A. 2 I bands
B. 2 Z bands
C. 2 A bands
D. 2 H bands
Answer» C. 2 A bands
44.

The connective tissue that surrounds individual fibers is __________

A. Fascia
B. Epimysium
C. Endomysium
D. Perimysium
Answer» D. Perimysium
45.

Which of the following is an invagination of the muscle cell’s sarcolemma?

A. Cisternae
B. Microtubules
C. T tubules
D. Sarcoplasmic reticula
Answer» D. Sarcoplasmic reticula
46.

Where do T-lymphocytes develop into fully competent but not activated T-cells?

A. The thymus gland
B. The lymph nodes
C. The thyroid gland
D. The bone marrow
Answer» B. The lymph nodes
47.

Which of the following is the largest immunoglobulin?

A. IgA
B. IgE
C. IgG
D. IgM
Answer» E.
48.

Which of the following antibody first reaches the site of infection?

A. IgA
B. IgE
C. IgG
D. IgM
Answer» E.
49.

The antibody present in secretions like tears and saliva is ____________

A. IgA
B. IgE
C. IgG
D. IgM
Answer» B. IgE
50.

Which of the following are known as helix breakers?

A. Proline and glycine
B. Isoleucine and leucine
C. Valine
D. Threonine
Answer» B. Isoleucine and leucine