Question 1

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

Accepted Answer

Homologous chromosomes carry genetic information for the same set of hereditary characteristics, but originate from different parents; sister chromatids are identical copies formed during DNA replication.

Question 2

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

Accepted Answer

$$23$$

Question 3

Which event during meiosis is primarily responsible for increasing genetic variation among offspring?

Accepted Answer

Crossing over between homologous chromosomes during Prophase I

Question 4

During which phase of meiosis do homologous chromosomes separate, reducing the chromosome number from diploid to haploid?

Accepted Answer

Anaphase I

Question 5

If a diploid cell in a plant has $$2n = 30$$ chromosomes, how many chromosomes will be present in each nucleus after mitosis and after meiosis, respectively?

Accepted Answer

After mitosis: $$30$$; after meiosis: $$15$$

Question 6

Which process ensures that offspring produced by sexual reproduction are genetically unique from their parents and siblings?

Accepted Answer

Crossing over and independent assortment during meiosis

Question 7

What is the result of meiosis in human females?

Accepted Answer

One functional gamete (egg) and three polar bodies

Question 8

Which of the following best explains independent assortment during meiosis?

Accepted Answer

The random orientation of tetrads during Metaphase I leads to different combinations of maternal and paternal chromosomes in gametes.

Question 9

Which of the following is NOT a difference between mitosis and meiosis?

Accepted Answer

Both mitosis and meiosis produce four daughter cells.

Question 10

A genetic disorder is caused by a failure of homologous chromosomes to separate during Anaphase I of meiosis. What is this phenomenon called?

Accepted Answer

Nondisjunction

Question 11

Which equation correctly represents the chromosome number in a diploid cell after meiosis?

Accepted Answer

$$n = \frac{2n}{2}$$

Question 12

Which stage of meiosis is most directly responsible for the formation of tetrads?

Accepted Answer

Prophase I

Question 13

Why do gametes produced by meiosis have half the chromosome number of somatic cells?

Accepted Answer

Because homologous chromosomes are separated during meiosis I

Question 14

Which of the following scenarios would most likely result in increased genetic variation in a population?

Accepted Answer

Sexual reproduction involving crossing over and independent assortment

Question 15

During which phase of meiosis do sister chromatids separate?

Accepted Answer

Anaphase II

Question 16

A cell undergoes meiosis and produces four gametes. If a mutation occurs during crossing over in Prophase I, what is the most likely outcome?

Accepted Answer

Each gamete may carry a unique combination of alleles, increasing genetic diversity.

Question 17

Which of the following best describes the outcome of fertilization in humans?

Accepted Answer

Fusion of two haploid gametes to form a diploid zygote

Question 18

Which of the following mechanisms does NOT contribute to genetic variation during meiosis?

Accepted Answer

Replication of DNA during S phase

Question 19

If a male undergoes meiosis, how many genetically unique gametes are produced from one diploid cell?

Accepted Answer

Four

Question 20

Which of the following is a direct result of the random orientation of tetrads during Metaphase I?

Accepted Answer

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

Meiosis & Sexual Life Cycles: Inheritance of Genes and Genetic Variation

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