Campbell Biology in Focus - Chapter 10 - Meiosis - Practice Questions

If a horticulturist breeding gardenias succeeds in having a single plant with a particularly desirable set of traits, which of the following would be her most probable and efficient route to establishing a line of such plants?

Clone the plant asexually to produce an identical one.

Which of the following descriptions correctly defines a genome?

the complete set of an organism's genes

Which of the following is the smallest unit that would contain a complete copy of the entire human genome?

one human somatic cell

If an organism is diploid and a certain gene found in the organism has 18 known alleles

(variants), then any given organism of that species can/must have which of the following?

at most, 2 alleles for that gene

Which of the following is a true statement about sexual versus asexual reproduction?

In sexual reproduction, individuals transmit 50% of their genes to each of their offspring.

At which stage of mitosis are chromosomes usually photographed in the preparation of a karyotype?

metaphase

Which of the following is true of a species that has a chromosome number of 2n = 16?

Each cell has eight homologous pairs.

Which of these statements is true?

In humans, the 23rd pair, the sex chromosomes, determines whether the person is female

(XX) or male (XY).

The human X and Y chromosomes

include genes that determine an individual's sex.

Which of the following describes a karyotype?

organized images of a cell's chromosomes

Which of the following types of cells would be produced by meiosis?

a haploid animal cell

Which of these is a way that the sexual life cycle increases genetic variation in a species?

by allowing crossing over

A given organism has 46 chromosomes in its karyotype. We can therefore conclude which of the following?

Its gametes must have 23 chromosomes.

The karyotype of one species of primate has 48 chromosomes. In a particular female, cell division malfunctions, and she produces one of her eggs with an extra chromosome (25). The most probable source of this error would be a mistake in which of the following?

either anaphase I or II

If a cell has completed the first meiotic division and is just beginning meiosis II, which of the following statements describes the contents of this cell?

It has half the amount of DNA of the cell that began meiosis.

Which of the following events might result in a human zygote with 45 chromosomes?

an error in either egg or sperm meiotic anaphase

After telophase I of meiosis, the chromosomal makeup of each daughter cell is

haploid, and the chromosomes are each composed of two chromatids.

How do cells at the completion of meiosis compare with cells that have replicated their DNA and are just about to begin meiosis?

They have half the number of chromosomes and one-fourth the amount of DNA.

Which of the following happens during meiosis I?

Homologous chromosomes of a pair are separated from each other.

Chromatids are separated from each other during which of the following processes?

during both mitosis and meiosis II

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

synapsis of chromosomes

Which of the following structures is found in a pair of homologous chromosomes?

four sister chromatids

When we see chiasmata under a microscope, that lets us know that which of the following processes has occurred?

prophase I

For the following question(s), match the key event of meiosis with the stages listed below.

I. prophase I V. prophase II

II. metaphase I VI. metaphase II

III. anaphase I VII. anaphase II

IV. telophase I VIII. telophase II

Homologous chromosomes are aligned at the equator of the spindle.

II

For the following question(s), match the key event of meiosis with the stages listed below.

I. prophase I V. prophase II

II. metaphase I VI. metaphase II

III. anaphase I VII. anaphase II

IV. telophase I VIII. telophase II

Centromeres of sister chromatids disjoin and chromatids separate.

VII

The following question refers to the essential steps in meiosis described below.

1. formation of four new nuclei, each with half the chromosomes present in the parental nucleus

2. alignment of homologous chromosomes at the metaphase plate

3. separation of sister chromatids

4. separation of the homologs; no uncoupling of the centromere

5. synapsis; chromosomes moving to the middle of the cell in pairs

Which of the steps take(s) place in both mitosis and meiosis?

3

For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes?

approximately 8.4 million

Independent assortment of chromosomes during meiosis is a result of

the random and independent way in which each pair of homologous chromosomes lines up at

the metaphase plate during meiosis I.

During which process does independent assortment of chromosomes occur?

during meiosis I only

Which of the following statements best describes how often crossing over occurs in humans?

at least 1-3 times per chromosome pair

When homologous chromosomes cross over, what is the result?

Specific proteins break the two strands of nonsister chromatids and re-join them.

Refer to the drawings in Figure 10.2 of a single pair of homologous chromosomes as they might appear during various stages of either mitosis or meiosis. Which diagram represents anaphase I of meiosis?

I

How is natural selection related to sexual reproduction as opposed to asexual reproduction?

Sexual reproduction results in many new gene combinations, some of which will lead to

differential reproduction.

A human cell containing 22 autosomes and a Y chromosome is

a sperm.

Homologous chromosomes move toward opposite poles of a dividing cell during

meiosis I