$$2^{23} = 8.4$$ \times $$10^6$$

Question 1

Which of the following best describes the genetic content of a human egg cell?

Accepted Answer

It contains 23 unique chromosomes, each with hundreds or thousands of genes.

Question 2

What is the primary outcome of fertilization between a human egg and sperm?

Accepted Answer

A diploid zygote with 46 chromosomes is formed, containing homologous pairs from each parent.

Question 3

Which process ensures that each daughter cell receives an identical set of chromosomes during cell division?

Accepted Answer

Mitosis

Question 4

During which phase of the cell cycle does DNA replication occur?

Accepted Answer

S phase

Question 5

A cell with 23 chromosomes, each consisting of two sister chromatids, is best described as:

Accepted Answer

Haploid (1N), after DNA replication

Question 6

Which of the following mechanisms contributes most directly to genetic diversity in gametes?

Accepted Answer

Homologous recombination (crossing over) during prophase I of meiosis

Question 7

If a human cell fails to attach all chromosomes to the spindle during mitosis, which checkpoint will prevent progression?

Accepted Answer

Spindle assembly checkpoint (M phase)

Question 8

Which statement about homologous chromosomes is correct?

Accepted Answer

They are the same size, contain the same genes in the same locations, but may have different alleles.

Question 9

How many possible combinations of maternal and paternal chromosomes can be produced by independent assortment during human meiosis?

Accepted Answer

$$2^{23} = 8.4$$ 	imes $$10^6$$

Question 10

A geneticist observes a cell with two copies of each chromosome, each consisting of two sister chromatids. What is the ploidy and stage of this cell?

Accepted Answer

Diploid (2N), after DNA replication in S phase

Question 11

Which event occurs during prophase I of meiosis but not during mitosis?

Accepted Answer

Homologous chromosomes pair and undergo crossing over

Question 12

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

Accepted Answer

They are only active when bound to the appropriate cyclin, regulating cell cycle progression.

Question 13

A mutation prevents the formation of the contractile ring during cytokinesis in animal cells. What is the most likely outcome?

Accepted Answer

The cell will not divide its cytoplasm, resulting in a multinucleated cell.

Question 14

Which of the following best explains why sister chromatids are not considered separate chromosomes after DNA replication?

Accepted Answer

They are attached at the centromere and represent identical copies of the same chromosome.

Question 15

A patient is found to have a genetic disorder caused by a mutation in the CF gene. On which chromosome would you expect to find this gene?

Accepted Answer

Chromosome 7

Question 16

Which of the following is a direct result of independent assortment during meiosis I?

Accepted Answer

Each gamete receives a random combination of maternal and paternal chromosomes.

Question 17

If a cell at the end of meiosis I contains 23 chromosomes, each with two sister chromatids, what is its ploidy?

Accepted Answer

Haploid (1N)

Question 18

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

Accepted Answer

Mitosis produces diploid cells, while meiosis II produces haploid cells.

Question 19

A researcher observes a cell with 46 chromosomes, each consisting of a single chromatid, after cell division. Which process most likely occurred?

Accepted Answer

Mitosis

Question 20

Which of the following events is unique to meiosis and does NOT occur during mitosis?

Accepted Answer

Formation of chiasmata between homologous chromosomes

Cell Division and Chromosome Heredity: Mitosis and Meiosis in Human Genetics

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