Explore topic-wise MCQs in Biochemistry.

This section includes 17 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Passage of a cell through stages of cell cycle is controlled by a protein kinase that phosphorylates many different proteins at appropriate times.

A. Cdk activating kinase
B. Cyclin-dependent kinase
C. Cyclins
D. Tyrosine kinase
Answer» C. Cyclins
2.

Which of the following occurs in meiosis but not in mitosis?

A. Attachment of spindle fibers to kinetochore
B. Replication of DNA prior to start of cell division
C. Separation of sister chromatids at anaphase
D. Pairing of homologous chromosomes at metaphase plate
Answer» E.
3.

At which cell cycle checkpoint, cell cycle is halted if cell’s DNA is damaged?

A. G1 – S
B. S – G2
C. G2 – M
D. G0 – G1
Answer» B. S – G2
4.

At the end of each phase of cell cycle cyclins activating Cdks in that phase are inactivated irreversibly by _____________

A. Multiple phosphorylations
B. De-phosphorylation
C. Ubiquitinylation
D. Destabilizing by proteolysis in a proteosome
Answer» E.
5.

Cyclin dependent kinases which control progression through cell cycle checkpoints are totally activated by which of the following?

A. Binding to cyclin, plus phosphorylation by a Cdk activating protein kinase
B. Binding to cyclins
C. Phosphorylation by Cdk activating protein kinase
D. Phosphorylation by a tyrosine kinase
Answer» B. Binding to cyclins
6.

Cdk2/cyclinE functions in ____________

A. G2/M transition
B. G2
C. M
D. G1/S transition
Answer» E.
7.

What is Ubiquitin?

A. Protein kinase
B. Protease
C. Component of the electron transport system
D. Protein that tags another protein for proteolysis
Answer» E.
8.

WHICH_OF_THE_FOLLOWING_OCCURS_IN_MEIOSIS_BUT_NOT_IN_MITOSIS??$

A. Attachment of spindle fibers to kinetochore
B. Replication of DNA prior to start of cell division
C. Separation of sister chromatids at anaphase
D. Pairing of homologous chromosomes at metaphase plate
Answer» E.
9.

Passage_of_a_cell_through_stages_of_cell_cycle_is_controlled_by_a_protein_kinase_that_phosphorylates_many_different_proteins_at_appropriate_times$

A. Cdk activating kinase
B. Cyclin-dependent kinase
C. Cyclins
D. Tyrosine kinase
Answer» C. Cyclins
10.

At which cell cycle checkpoint, cell cycle is halted if cell’s DNA is damage?#

A. G<sub>1</sub> – S
B. S – G<sub>2</sub>
C. G<sub>2</sub> – M
D. G<sub>0</sub> – G<sub>1</sub>
Answer» B. S ‚Äö√Ñ√∂‚àö√ë‚àö¬® G<sub>2</sub>
11.

At the end of each phase of cell cycle cyclins activating Cdks in that phase are inactivated irreversibly by

A. Multiple phosphorylations
B. De-phosphorylation
C. Ubiquitinylation
D. Destabilizing by proteolysis in a proteosome
Answer» E.
12.

Cyclin dependent kinases which control progression through cell cycle checkpoints are totally activated by which of the following

A. Binding to cyclin, plus phosphorylation by a Cdk activating protein kinase
B. Binding to cyclins
C. Phosphorylation by Cdk activating protein kinase
D. Phosphorylation by a tyrosine kinase
Answer» B. Binding to cyclins
13.

In which phase of cell cycle is DNA replicated?

A. G<sub>1</sub> phase
B. S phase
C. G<sub>2</sub> phase
D. M phase
Answer» C. G<sub>2</sub> phase
14.

Cdk2/cyclinE functions in

A. G<sub>2</sub>/M transition
B. G<sub>2</sub>
C. M
D. G<sub>1</sub>/S transition
Answer» E.
15.

Ubiquitin is a

A. Protein kinase
B. Protease
C. Component of the electron transport system
D. Protein that tags another protein for proteolysis
Answer» E.
16.

Which of the following statements regarding cyclins is not correct?

A. They can become linked to ubiquitin
B. They catalyze the phosphorylation of protein
C. They contain specific amino acid sequence that target them for proteolysis
D. They are activated and degraded during cell cycle
Answer» E.
17.

Which of the following statements regarding cyclin-dependent protein kinase is not correct?

A. Their activity is regulated by cyclins
B. They can alter the activity of proteins involve in the progression of cells through cell cycle
C. Their activity fluctuates during cell cycle
D. Each type of cell contains one specific form
Answer» D. Each type of cell contains one specific form