Question 1

Which of the following statements best distinguishes asexual from sexual reproduction?

Accepted Answer

Asexual reproduction produces offspring genetically identical to the parent, while sexual reproduction results in genetically unique offspring.

Question 2

In humans, which cells are haploid and what is their chromosome number?

Accepted Answer

Gametes; 23 chromosomes

Question 3

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

Accepted Answer

Prophase I; it increases genetic variation by exchanging DNA between homologous chromosomes

Question 4

Which of the following equations correctly represents the number of possible chromosome combinations due to independent assortment in a gamete, where $$n is $$the haploid number?

Accepted Answer

$$2^n$$

Question 5

A diploid organism has a total of 8 chromosomes. After meiosis, how many chromosomes will each gamete contain?

Accepted Answer

4

Question 6

Which of the following events occurs in meiosis I but not in mitosis?

Accepted Answer

Alignment of homologous pairs at the metaphase plate

Question 7

Why must fertilization and meiosis alternate in all sexual life cycles?

Accepted Answer

To maintain a constant chromosome number across generations

Question 8

Which of the following best describes the difference between autosomes and sex chromosomes in humans?

Accepted Answer

Autosomes are present in pairs in both sexes, while sex chromosomes differ between males and females.

Question 9

A plant species exhibits alternation of generations. Which of the following statements is true regarding its life cycle?

Accepted Answer

The sporophyte is diploid and produces haploid spores by meiosis.

Question 10

Which process is responsible for the formation of recombinant chromosomes during meiosis?

Accepted Answer

Crossing over

Question 11

If a mutation occurs in a gene located at a specific locus on a chromosome, what is the most likely result?

Accepted Answer

A new allele of the gene will be created at that locus.

Question 12

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

Accepted Answer

Replication of DNA during S phase

Question 13

During which stage of meiosis are homologous chromosomes separated?

Accepted Answer

Anaphase I

Question 14

A human zygote is formed by the fusion of two gametes. What is the chromosome number of the zygote?

Accepted Answer

46

Question 15

Which of the following best explains why siblings from the same parents are genetically different from each other?

Accepted Answer

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

Question 16

Which of the following is a correct sequence of events in meiosis I?

Accepted Answer

Prophase I → Metaphase I → Anaphase I → Telophase I

Question 17

Which of the following statements about sister chromatids is true?

Accepted Answer

They are genetically identical before crossing over.

Question 18

In which type of organism is the only diploid stage the zygote, with the rest of the life cycle being haploid?

Accepted Answer

Most fungi and some protists

Question 19

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

Accepted Answer

It holds homologous chromosomes together during synapsis in prophase I.

Question 20

A geneticist is studying a cell with 12 chromosomes at the start of meiosis. After meiosis II, how many chromosomes will each daughter cell have?

Accepted Answer

6

Meiosis and the Sexual Life Cycle: Study Notes

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드