Over $$8 \times 10^6$ possibilities

Question 1

Which of the following best describes the function of the protein Spo11 during meiosis?

Accepted Answer

Spo11 catalyzes the formation of double strand breaks in DNA, initiating recombination.

Question 2

During meiosis, crossing over occurs between which chromatids?

Accepted Answer

Non-sister chromatids of homologous chromosomes

Question 3

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

Accepted Answer

23

Question 4

Which process increases genetic variation by creating new gene combinations during meiosis?

Accepted Answer

Crossing over

Question 5

How many possible combinations of chromosomes can result from independent assortment in humans ($$2n = 46$$)?

Accepted Answer

Over $$8 	imes 10^6$ possibilities

Question 6

Which of the following is NOT a source of genetic variation in sexual life cycles?

Accepted Answer

DNA replication

Question 7

A diploid cell ($$2n) $$undergoes meiosis. What is the chromosome number of the resulting cells?

Accepted Answer

$$n$$

Question 8

Which event occurs during synapsis in meiosis?

Accepted Answer

Homologous chromosomes pair up to form a tetrad

Question 9

Why does genetic variation increase the chances of a species' survival?

Accepted Answer

It allows populations to adapt to changing environments, such as developing antibiotic resistance.

Question 10

Which of the following best describes homologous chromosomes?

Accepted Answer

They carry information for the same traits at the same locations, but may have different alleles.

Question 11

During metaphase I of meiosis, what is the arrangement of chromosomes?

Accepted Answer

Homologous pairs (tetrads) align at the metaphase plate

Question 12

Which of the following statements about fertilization is correct?

Accepted Answer

It combines two haploid gametes to form a diploid zygote.

Question 13

If a mutation prevents Spo11 from functioning, what would most likely happen during meiosis?

Accepted Answer

Crossing over would not occur, reducing genetic variation.

Question 14

Which stage of meiosis is responsible for the separation of homologous chromosomes?

Accepted Answer

Anaphase I

Question 15

A cell with duplicated chromosomes is labeled as:

Accepted Answer

2n, with duplicated chromosomes

Question 16

Which of the following is a key difference between mitosis and meiosis?

Accepted Answer

Meiosis produces four genetically unique haploid cells, while mitosis produces two identical diploid cells.

Question 17

Which formula represents the number of possible gamete combinations due to independent assortment, given $$n$$ chromosome pairs?

Accepted Answer

$$2^n$$

Question 18

In a scenario where a mouse inherits a mutation in a gene involved in crossing over, what is a likely consequence?

Accepted Answer

The mouse's gametes will have reduced genetic diversity.

Question 19

Which of the following best explains why random fertilization contributes to genetic variation?

Accepted Answer

Any sperm can fuse with any egg, creating a unique combination of parental genes.

Question 20

A researcher is studying yeast cells undergoing meiosis. Which phase would she observe to see the formation of tetrads?

Accepted Answer

Prophase I

Meiosis and Sexual Life Cycles: Study Notes for BIO-101

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