Question 1

Which of the following best describes the main outcome of meiosis as depicted in the first image?

Accepted Answer

One diploid cell divides to produce four haploid cells, each with half the chromosome number of the original cell.

Question 2

During which phase of meiosis are homologous chromosomes separated, and what is the ploidy of the resulting cells?

Accepted Answer

Meiosis I; haploid

Question 3

Referencing the karyotype in the second image, what is the chromosome number and ploidy of a typical human somatic cell?

Accepted Answer

$$2n = 46$$, diploid

Question 4

Which process, illustrated in the third image, is responsible for restoring the diploid chromosome number in sexually reproducing organisms?

Accepted Answer

Fertilization

Question 5

Based on the fourth image, what is the key genetic difference between sexual reproduction and organismal cloning?

Accepted Answer

Cloning results in offspring genetically identical to the donor, while sexual reproduction produces genetically unique offspring.

Question 6

During which stage of meiosis I, as shown in the fifth image, does crossing over (genetic recombination) typically occur?

Accepted Answer

Prophase I

Question 7

In the sixth image, what is the main event occurring during anaphase II of meiosis?

Accepted Answer

Sister chromatids are separated.

Question 8

Which cytoskeletal structure, as shown in the seventh image, is responsible for the dynamic instability that drives chromosome movement during mitosis and meiosis?

Accepted Answer

Microtubules

Question 9

The eighth image shows vesicle transport along microtubules. Which motor protein moves vesicles toward the plus end of microtubules?

Accepted Answer

Kinesin

Question 10

Referencing the ninth image, which region of the myosin molecule binds ATP and is responsible for its motor activity?

Accepted Answer

Globular head

Question 11

In the sliding-filament model of muscle contraction (see the eleventh image), which band remains unchanged during contraction?

Accepted Answer

A band

Question 12

According to the twelfth image, what is the effect of increased $$Ca^{2+}$$ concentration on the actin filament in skeletal muscle?

Accepted Answer

It exposes the myosin binding site.

Question 13

Which of the following best explains the regulatory role of p53 in the cell cycle, as described in the study materials?

Accepted Answer

p53 arrests the cell cycle in response to DNA damage by inducing p21, which inhibits cyclin-Cdk complexes.

Question 14

Which enzyme is responsible for relieving supercoiling ahead of the replication fork during DNA replication, as shown in the images?

Accepted Answer

Topoisomerase

Question 15

During DNA replication, which enzyme synthesizes short RNA primers to initiate DNA synthesis?

Accepted Answer

Primase

Question 16

What is the function of telomerase, as depicted in the telomere extension image?

Accepted Answer

It adds repetitive DNA sequences to the ends of chromosomes to prevent shortening during replication.

Question 17

Which of the following best describes the order of signaling molecules in the EGF pathway leading to S-phase entry, as described in the study materials?

Accepted Answer

7 (EGF) → 3 (RTK) → 9 (Ras-GTP) → 4 (Raf) → 6 (MEK) → 1 (MAPK) → 8 (c-Jun) → 10 (Cyclin D-Cdk4/6) → 2 (Rb) → 5 (E2F)

Question 18

A mutation in the gene encoding for cohesin would most likely result in which of the following meiotic errors?

Accepted Answer

Premature separation of sister chromatids during meiosis I

Question 19

Which protein complex is responsible for degrading securin and allowing separase to cleave cohesin during anaphase?

Accepted Answer

Anaphase-promoting complex (APC)

Question 20

A patient with a mutation in the ATM gene is likely to have defects in which cellular process?

Accepted Answer

DNA damage checkpoint activation

Meiosis, Sexual Reproduction, and Cell Cycle Regulation: Study Notes for Cell Biology

Study Guide - Practice Questions

Study Guide - Flashcards