Question 1

Which of the following statements best describes the difference between somatic cells and germ cells in humans?

Accepted Answer

Somatic cells are body cells other than gametes, while germ cells are gametes (sperm and egg cells).

Question 2

A homologous pair of chromosomes is characterized by which of the following features?

Accepted Answer

They are nearly identical in size, banding pattern, and centromere location, and have the same genes but not necessarily the same alleles.

Question 3

If a human cell is in the G2 phase of the cell cycle, how many chromatids does it contain?

Accepted Answer

$$92$$

Question 4

During which phase of mitosis do sister chromatids separate and move toward opposite poles?

Accepted Answer

Anaphase

Question 5

Which type of spindle microtubule attaches to the centromere of each chromosome during mitosis?

Accepted Answer

Kinetochore microtubules

Question 6

What is the genetic outcome of mitosis in terms of chromosome number and genetic identity?

Accepted Answer

Two daughter cells, each with the same chromosome number as the mother cell and genetically identical (unless a mutation occurs).

Question 7

A cell-cycle checkpoint gene is mutated and fails to function. What is a likely consequence?

Accepted Answer

The cell may progress through the cell cycle with damaged DNA, increasing the risk of cancer or other diseases.

Question 8

Which equation correctly represents the chromosome number in human gametes produced by meiosis?

Accepted Answer

$$n = 23$$

Question 9

During meiosis I, which event is responsible for increasing genetic diversity among gametes?

Accepted Answer

Crossing over between homologous chromosomes

Question 10

Which of the following best describes the difference between meiosis I and meiosis II?

Accepted Answer

Meiosis I reduces the chromosome number by half, while meiosis II separates sister chromatids.

Question 11

In oogenesis, why does only one cell per meiosis become an egg?

Accepted Answer

Because the division in meiosis I is asymmetric, producing a large secondary oocyte and a small polar body.

Question 12

Which stage of prophase I in meiosis is characterized by the formation of the synaptonemal complex and the beginning of crossing over?

Accepted Answer

Zygotene

Question 13

A male patient has a mutation that prevents the formation of polar bodies during spermatogenesis. What is the most likely outcome?

Accepted Answer

There will be no effect, as polar bodies are not formed during spermatogenesis.

Question 14

Which of the following events occurs during metaphase I of meiosis?

Accepted Answer

Tetrads (bivalents) organize along the metaphase plate.

Question 15

If a human zygote is formed by the fusion of two gametes, what is the resulting chromosome number?

Accepted Answer

$$2n = 46$$

Question 16

Which process ensures that each daughter cell receives the same complement of chromosomes during mitosis?

Accepted Answer

Separation and sorting of sister chromatids

Question 17

Which of the following is a function of cyclin-dependent kinases (CDKs) in the cell cycle?

Accepted Answer

They form activated complexes that regulate progression through the cell cycle.

Question 18

Which of the following best explains why genetic recombination during meiosis is important for evolution?

Accepted Answer

It increases genetic diversity, providing raw material for natural selection.

Question 19

A cell with genotype $$Bb is $$described as:

Accepted Answer

Heterozygous

Question 20

Which event distinguishes meiosis I from mitosis?

Accepted Answer

Formation of tetrads and crossing over between homologous chromosomes

Chromosome Transmission During Cell Division and Sexual Reproduction

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