Question 1

Which of the following best describes the semiconservative model of DNA replication?

Accepted Answer

Each daughter DNA molecule consists of one old strand and one new strand.

Question 2

During the cell cycle, which phase is primarily responsible for the synthesis of DNA?

Accepted Answer

S phase

Question 3

A mutation in the p53 gene is most likely to result in which of the following cellular outcomes?

Accepted Answer

Uncontrolled cell growth due to failure to suppress the cell cycle

Question 4

Which enzyme is responsible for joining Okazaki fragments during DNA replication?

Accepted Answer

DNA ligase

Question 5

In the lac operon, what is the role of the inducer?

Accepted Answer

It inactivates the repressor, allowing transcription to occur.

Question 6

Which of the following is a characteristic of endothermic animals?

Accepted Answer

They generate heat by metabolism.

Question 7

A cell that does not receive a go-ahead signal at the G1 checkpoint will most likely:

Accepted Answer

Enter the G0 phase and stop dividing.

Question 8

Which of the following best explains the function of telomerase in germ cells?

Accepted Answer

It catalyzes the lengthening of telomeres, maintaining chromosome integrity.

Question 9

Which of the following statements about the trp operon is correct?

Accepted Answer

It is a repressible operon that is usually on.

Question 10

Which of the following is a real-life example of negative feedback in endocrine signaling?

Accepted Answer

Elevated blood glucose triggers insulin release, which lowers blood glucose.

Question 11

Which of the following best describes the antiparallel arrangement of DNA?

Accepted Answer

The two DNA strands run in opposite directions.

Question 12

Which of the following is a function of protein kinases in signal transduction pathways?

Accepted Answer

They transfer phosphate groups from ATP to proteins.

Question 13

A patient with a mutation in the Ras proto-oncogene is most likely to experience:

Accepted Answer

Uncontrolled cell growth, increasing cancer risk.

Question 14

Which of the following is TRUE regarding the difference between DNA and RNA?

Accepted Answer

DNA contains deoxyribose sugar, while RNA contains ribose.

Question 15

Which of the following is a plausible consequence of defective nucleotide excision repair mechanisms?

Accepted Answer

Accumulation of DNA damage, leading to genetic disorders or cancer.

Question 16

Which of the following best describes the role of enhancers in gene regulation?

Accepted Answer

They are distal control elements that bind transcription factors to regulate transcription.

Question 17

Which of the following is a key difference between mitosis and binary fission?

Accepted Answer

Mitosis involves the division of the nucleus, while binary fission does not.

Question 18

Which of the following equations correctly represents the relationship between heat transfer and temperature gradient in countercurrent exchange?

Accepted Answer

$$Q = k \cdot (T_1$ - T_2$)$$

Question 19

A cell exposed to a high concentration of growth factors is most likely to:

Accepted Answer

Begin dividing in response to the growth factors.

Question 20

Which of the following best describes alternative RNA splicing?

Accepted Answer

It produces different mRNA molecules from the same primary transcript by treating different RNA segments as exons or introns.

Comprehensive Study Notes: Molecular Genetics, Cell Division, Gene Regulation, and Animal Physiology

Study Guide - Practice Questions