Question 1

Which of the following best describes the main difference between asexual and sexual reproduction?

Accepted Answer

Asexual reproduction produces genetically identical offspring, while sexual reproduction produces genetically unique offspring.

Question 2

During which phase of meiosis does crossing over occur, and what is its significance?

Accepted Answer

Crossing over occurs during prophase I and increases genetic variation among offspring.

Question 3

A human somatic cell contains 46 chromosomes. After meiosis, how many chromosomes will each gamete contain?

Accepted Answer

23 chromosomes

Question 4

Which of the following statements about homologous chromosomes is correct?

Accepted Answer

They carry genes controlling the same inherited characters but may have different alleles.

Question 5

If an organism has a diploid number of 8 ($$2n = 8$$), how many possible combinations of chromosomes can be produced by independent assortment during meiosis?

Accepted Answer

$$2^4 = 16$

Question 6

Which event is unique to meiosis and does NOT occur in mitosis?

Accepted Answer

Synapsis and crossing over between homologous chromosomes

Question 7

A mutation occurs in a gene located at a specific locus on a chromosome. What is the most likely result of this mutation in terms of genetic variation?

Accepted Answer

It will create a new allele, increasing genetic variation.

Question 8

Which of the following best explains why siblings from the same parents can look very different from each other?

Accepted Answer

Independent assortment, crossing over, and random fertilization create unique combinations of alleles in each offspring.

Question 9

During which stage of meiosis are homologous chromosomes separated?

Accepted Answer

Anaphase I

Question 10

Which of the following is true regarding the products of meiosis in animals?

Accepted Answer

Four haploid cells are produced, each genetically distinct from the parent and each other.

Question 11

A plant species has a life cycle that includes both multicellular haploid and multicellular diploid stages. What is this type of life cycle called?

Accepted Answer

Alternation of generations

Question 12

Which of the following mechanisms does NOT contribute to genetic variation in sexually reproducing organisms?

Accepted Answer

Replication of DNA during interphase

Question 13

In humans, how many autosomes are present in a gamete?

Accepted Answer

22

Question 14

Which of the following best describes the role of the synaptonemal complex during meiosis?

Accepted Answer

It holds homologous chromosomes together during synapsis, facilitating crossing over.

Question 15

A cell with a diploid number of 10 ($$2n = 10) $$undergoes meiosis. How many chromosomes will each daughter cell have at the end of meiosis II?

Accepted Answer

5

Question 16

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

Accepted Answer

Mitosis conserves chromosome number, while meiosis reduces it by half.

Question 17

If a sperm cell containing an X chromosome fertilizes an egg, what will be the sex chromosome composition of the resulting zygote?

Accepted Answer

XX

Question 18

Which of the following best explains why only diploid cells can undergo meiosis?

Accepted Answer

Only diploid cells have homologous pairs of chromosomes that can be separated.

Question 19

A geneticist observes that a certain gene is located at the same position on both members of a homologous chromosome pair. What is this position called?

Accepted Answer

Locus

Question 20

Which of the following is a direct result of random fertilization in humans?

Accepted Answer

Each zygote has a unique combination of alleles, with about 70 trillion possible combinations.

Meiosis and Sexual Life Cycles: Mechanisms of Heredity and Genetic Variation

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