Biology Test Biology Cellular and Molecular 5

Question 1

What is the function of restriction enzymes in molecular biology?

Accepted Answer

They cut DNA at specific recognition sequences

Answer

Restriction enzymes (endonucleases) recognize and cleave specific short DNA sequences, producing fragments used in cloning and genetic analysis.

Question 2

Which process allows cells to engulf large particles or other cells by forming membrane vesicles?

Accepted Answer

Phagocytosis

Answer

Phagocytosis is a form of endocytosis in which the cell membrane engulfs large particles like bacteria, forming a phagosome.

Question 3

What is epigenetics?

Accepted Answer

Heritable changes in gene expression without altering the DNA sequence

Answer

Epigenetics refers to changes in gene expression caused by modifications like DNA methylation and histone acetylation that do not change the underlying DNA sequence.

Question 4

In CRISPR-Cas9 gene editing, what is the role of the guide RNA (gRNA)?

Accepted Answer

It directs the Cas9 enzyme to a specific DNA sequence

Answer

The guide RNA is complementary to the target DNA sequence and directs the Cas9 nuclease to the correct location in the genome for cleavage.

Question 5

What is the purpose of the ubiquitin-proteasome pathway?

Accepted Answer

Tagging and degrading damaged or misfolded proteins

Answer

Ubiquitin molecules are attached to proteins marked for destruction, directing them to the proteasome where they are degraded into peptides.

Biology Practice Test

Biology Practice Test

Biology Test Biology Cellular and Molecular 5