Home
General Knowledge (GK)
General Science and Nature
- Biology MCQs

Home

General Science and Nature

Biology MCQs

Cell Biology

All MCQs

Cell Biology

Sign in

Hay, Enter your details to get sign in to your account

Forgot Password?

Don't have an account Sign up

Sign up

Hay, Enter your details to get sign up to your account

Have an account already Sign in

81.

Which process is responsible for the bulk transport of fluids into a cell through vesicle formation?

Transcytosis

Pinocytosis

Phagocytosis

Exocytosis

Explanation Comments

Answer: Pinocytosis

Explanation:

Pinocytosis, also known as "cell drinking," involves the engulfment of extracellular fluid and dissolved solutes into small vesicles by the cell membrane.

Hide Explanation

82.

What is the main role of cyclin-dependent kinases (CDKs) in the cell cycle?

Regulating the progression of the cell cycle

Degrading damaged proteins

Initiating DNA replication

Facilitating cell-cell communication

Explanation Comments

Answer: Regulating the progression of the cell cycle

Explanation:

Cyclin-dependent kinases (CDKs) are enzymes that, when bound to cyclins, phosphorylate target proteins to regulate the progression of the cell cycle.

Hide Explanation

83.

Which of the following processes is primarily responsible for generating the proton gradient used in ATP synthesis in mitochondria?

Glycolysis

Krebs cycle

Electron transport chain

Fermentation

Explanation Comments

Answer: Electron transport chain

Explanation:

The electron transport chain in the inner mitochondrial membrane creates a proton gradient across the membrane, which drives ATP synthesis by ATP synthase.

Hide Explanation

84.

Which type of RNA molecule is involved in regulating gene expression by binding to complementary mRNA sequences and preventing their translation?

rRNA

miRNA

tRNA

mRNA

Explanation Comments

Answer: miRNA

Explanation:

MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression by binding to complementary sequences on target mRNAs, leading to their degradation or inhibition of translation.

Hide Explanation

85.

In which part of the chloroplast does the light-independent (Calvin) cycle take place?

Thylakoid lumen

Stroma

Thylakoid membrane

Grana

Explanation Comments

Answer: Stroma

Explanation:

The Calvin cycle occurs in the stroma of the chloroplast, where it uses ATP and NADPH generated in the light-dependent reactions to fix carbon dioxide into organic molecules.

Hide Explanation

86.

Which molecule is responsible for linking glycolysis to the Krebs cycle by converting pyruvate into acetyl-CoA?

Phosphofructokinase

Hexokinase

Lactate dehydrogenase

Pyruvate dehydrogenase

Explanation Comments

Answer: Pyruvate dehydrogenase

Explanation:

Pyruvate dehydrogenase converts pyruvate, the end product of glycolysis, into acetyl-CoA, which then enters the Krebs cycle.

Hide Explanation

87.

What is the role of the enzyme superoxide dismutase (SOD) in the cell?

Synthesizing ATP

Catalyzing the dismutation of superoxide radicals

Breaking down hydrogen peroxide

Facilitating DNA replication

Explanation Comments

Answer: Catalyzing the dismutation of superoxide radicals

Explanation:

Superoxide dismutase (SOD) is an enzyme that catalyzes the conversion of superoxide radicals into oxygen and hydrogen peroxide, protecting the cell from oxidative damage.

Hide Explanation

88.

Which process involves the selective degradation of cellular components, such as damaged organelles, through the lysosomal pathway?

Necrosis

Exocytosis

Autophagy

Apoptosis

Explanation Comments

Answer: Autophagy

Explanation:

Autophagy is a cellular process that degrades and recycles damaged organelles and macromolecules through the lysosomal pathway, helping maintain cellular homeostasis.

Hide Explanation

89.

In eukaryotic cells, where does RNA splicing occur?

Golgi apparatus

Cytoplasm

Mitochondria

Nucleus

Explanation Comments

Answer: Nucleus

Explanation:

RNA splicing occurs in the nucleus, where introns are removed from pre-mRNA, and exons are joined together to form mature mRNA.

Hide Explanation

90.

Which component of the electron transport chain in mitochondria acts as a proton pump?

Cytochrome c

ATP synthase

Succinate dehydrogenase (Complex II)

NADH dehydrogenase (Complex I)

Explanation Comments

Answer: NADH dehydrogenase (Complex I)

Explanation:

NADH dehydrogenase (Complex I) is one of the complexes in the electron transport chain that pumps protons from the mitochondrial matrix to the intermembrane space, contributing to the proton gradient.

Hide Explanation

Quick Links

Cell Biology

Genetics and Molecular Biology

Evolutionary Biology

Physiology and Anatomy

Home
About
Blog
Contact