Question 1

Which of the following best explains why siblings from the same parents can have different traits, such as eye color or hair type?

Accepted Answer

Independent assortment and crossing over during meiosis create unique combinations of alleles in each gamete.

Question 2

A hydra reproduces by budding, producing offspring genetically identical to itself. What type of reproduction is this, and what is the genetic consequence?

Accepted Answer

Asexual reproduction; offspring are clones of the parent.

Question 3

During meiosis, homologous chromosomes are separated in which phase, and what is the result for the chromosome number in the daughter cells?

Accepted Answer

Anaphase I; daughter cells become haploid.

Question 4

If a human cell has 46 chromosomes, how many chromosomes will each gamete have after meiosis?

Accepted Answer

23

Question 5

Which event during meiosis is responsible for the exchange of genetic material between homologous chromosomes, increasing genetic variation?

Accepted Answer

Crossing over during prophase I

Question 6

What is the formula for the number of possible chromosome combinations due to independent assortment in gametes, and what is the value for humans?

Accepted Answer

The formula is $$2^n$$, where $$n is $$the haploid number; for humans, $$2^{23} = 8$$,388,608$$.

Question 7

Which of the following statements about meiosis and mitosis is correct?

Accepted Answer

Meiosis produces four genetically distinct haploid cells.

Question 8

A gene’s specific location on a chromosome is called its locus. If a gene for eye color is located at a particular locus, what does this mean?

Accepted Answer

The gene is found at a specific position on a chromosome.

Question 9

Which mechanism does NOT contribute to genetic variation in sexually reproducing organisms?

Accepted Answer

Replication of chromosomes during mitosis

Question 10

In humans, what is the result of fertilization between two gametes, each with $$2^{23}$$ possible chromosome combinations?

Accepted Answer

A zygote with $$2^{23}$$ 	imes $$2^{23} = 70$$,368,744,177,664$$ possible combinations

Question 11

Which of the following best describes the difference between homologous chromosomes and sister chromatids?

Accepted Answer

Homologous chromosomes carry genes for the same traits but may have different alleles; sister chromatids are identical copies formed during DNA replication.

Question 12

Which phase of meiosis is most directly responsible for the creation of recombinant chromosomes?

Accepted Answer

Prophase I

Question 13

A multicellular diploid organism produces haploid gametes through meiosis. What happens to the chromosome number after fertilization?

Accepted Answer

It doubles to become diploid.

Question 14

Which of the following is a direct consequence of mutations in DNA?

Accepted Answer

Creation of new alleles

Question 15

In plants, the alternation of generations involves both haploid and diploid multicellular stages. Which process restores the diploid state?

Accepted Answer

Fertilization

Question 16

Which of the following best describes the outcome of meiosis II?

Accepted Answer

Sister chromatids are separated, resulting in haploid cells.

Question 17

A karyotype is used in genetics to:

Accepted Answer

Visualize and analyze the number and structure of chromosomes in a cell.

Question 18

Which of the following is NOT a feature unique to meiosis (and not mitosis)?

Accepted Answer

Separation of sister chromatids during anaphase II

Question 19

If a plant has a diploid number of 8 ($$2n = 8$$), how many possible combinations of chromosomes can be produced in its gametes due to independent assortment?

Accepted Answer

$$2^8 = 256$

Meiosis and Sexual Life Cycles: Mechanisms of Genetic Variation

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