Deck 27: Chromosomes and Cell Division

Question 1

An entire cell cycle can be completed in about ________.

A) 1 to 2 hours
B) 24 hours
C) 48 hours
D) 1 week

Answer 1

B

Question 2

Which of the following phases of mitosis is not matched with the appropriate activities that occur during that phase?

A) anaphase: homologous pairs separate
B) telophase: new nuclear envelope forms, and the mitotic spindle disassembles
C) prophase: nuclear membrane disappears
D) metaphase: chromosomes line up in the center of the cell

Answer 2

A

Question 3

Cancer is associated with problems related to the regulation of ________.

A) mitosis
B) meiosis I
C) meiosis II
D) cytokinesis

Answer 3

A

Question 4

If a cell begins mitosis with 36 chromosomes, there will be ________ chromosomes in each cell after mitosis, and each daughter cell will be ________ genetically.

A) 36; identical
B) 36; different
C) 18; identical
D) 18; different

Question 5

The separation of daughter cells is called ________.

A) karyokinesis
B) mitosis
C) nucleosome
D) cytokinesis

Question 6

Oogenesis differs from spermatogenesis in ________.

A) the number of functional gametes produced
B) when it is completed
C) the size of gametes produced
D) All of the above are true.

Question 7

The exchange of genetic material during crossing over causes which of the following?

A) genetic variation
B) stasis
C) heterozygosity
D) homozygosity

Question 8

Human cells that have completed telophase I will each contain ________ chromosomes, which will be in a(n) ________ form.

A) 46; replicated
B) 46; unreplicated
C) 23; replicated
D) 23; unreplicated

Question 9

A process in which a sister chromatid inherited from the mother and a sister chromatid inherited from the father pair up and form tetrads and exchange DNA to form genetically diverse gametes is called ________.

A) cell cycle
B) prophase
C) cytokinesis
D) crossing over

Question 10

DNA that has wrapped around histones and is in a condensed form following interphase is called ________.

A) chromatin
B) nucleosomes
C) chromosomes
D) karyokinesis

Question 11

In which phase do the following events occur: the chromatin condenses into chromosomes, the nuclear membrane disintegrates, and the centrioles migrate to the poles as spindle fibers are organized?

A) interphase
B) anaphase
C) prophase
D) telophase

Question 12

In which phase of meiosis I do homologues separate?

A) prophase II
B) anaphase
C) metaphase I
D) anaphase I

Question 13

A process that is part of the cell cycle and parcels out the duplicated copies of genetic material for cell division in eukaryotes is called ________.

A) nucleosome
B) meiosis
C) histone
D) mitosis

Question 14

The most appropriate form of cell division for repairing an injured tissue is ________.

A) mitosis
B) meiosis
C) cytokinesis
D) cloning

Question 15

Polar bodies are unique products of ________.

A) cytokinesis
B) oogenesis
C) mitosis
D) spermatogenesis

Question 16

Children born with Down syndrome have inherited an extra chromosome, so their diploid number is 47 rather than 46 chromosomes. What is this genetic condition called?

A) trisomy 21
B) triploid
C) haploid 21
D) monoploidy

Question 17

A cell with a diploid number of 24 fails to undergo cytokinesis while performing mitosis, so the daughter cells do not form. How many chromosomes will be in the resulting cell?

A) 96
B) 48
C) 24
D) 12

Question 18

How do mitosis and meiosis differ from each other?

A) The goal of mitosis is to produce cells that are genetically identical to the original parent cell; the goal of meiosis is to produce cells that contain twice the number of chromosomes as the original parent cell.
B) The cells formed by mitosis are diploid; the cells formed by meiosis are haploid.
C) Mitosis results in the production of gametes; meiosis results in the production of cells, which are used for the organism's growth and replacement of damaged cells.
D) Synapsis and crossing over occur in mitosis to ensure new combinations of genetic material; synapsis and crossing over do not occur in meiosis.

Question 19

In which stage of mitosis does exchange of genetic material between chromosomes (crossing over) occur?

A) prophase I
B) anaphase I
C) prophase II
D) none of the above

Question 20

Which of the following combinations of sex chromosomes results in Klinefelter syndrome?

A) XO
B) XXX
C) XYY
D) XXY

Question 21

Crossing over occurs during ________ and is important because it ________.

A) telophase II; creates daughter cells
B) prophase I; generates variation
C) anaphase II; separates the homologous pairs
D) metaphase I; reduces the chromosome number by half

Question 22

The ________ cells are those body cells of humans that contain 23 chromosomes.

Question 23

Nondisjunction could occur during ________.

A) metaphase
B) telophase
C) anaphase II
D) prophase I

Question 24

A gene on the Y chromosome causes a rare disease. A woman married to a man with the disease has three children. The first two are daughters without the disease. The third is a son. What is the probability that the son will have the gene?

A) 0%
B) 25%
C) 50%
D) 75%
E) 100%

Question 25

You are looking at diagrams of cells in the process of division and are uncertain as to what process you are viewing (mitosis or meiosis). You determine that the cells you are looking at have 7 chromosomes. You can confidently assume that these cells are in which phase, based on this odd chromosome number?

A) metaphase
B) metaphase I
C) metaphase II
D) All of the above are true.

Question 26

The exchange of genetic material between nonsister chromatids of a homologous pair in meiosis is called ________.

Question 27

A picture of the arrangement of an individual's chromosomes by size and centromere location is called a(n) ________.

Question 28

The ________ are the 23rd pair of chromosomes that carry the traits that determine gender.

Question 29

XO sex chromosomes are responsible for the following syndrome.

A) Klinefelter syndrome
B) Turner syndrome
C) Jacob syndrome
D) trisomy 21

Question 30

________ is a syndrome that occurs in females who have only a single X chromosome (XO).

Question 31

The part of the cell cycle that is preparation for cell division and that precedes mitosis is called ________.

Question 32

What is decreased during the process of meiosis?

A) the size of chromosomes
B) the number of cells
C) the number of chromosomes
D) All of the above are true.

Question 33

Why is meiosis II needed for gamete (egg and sperm) production?

A) to generate genetic diversity
B) to make the gametes haploid
C) to get unreplicated chromosomes in the gametes
D) All of the above are true.

Question 34

If a sperm cell contains 6 chromosomes, it must have come from an original parent cell that contained ________ chromosomes.

A) 4
B) 6
C) 12
D) 24

Question 35

Two replicated chromosomes are joined together at a region on the chromosome called the ________.

Question 36

The process of oogenesis is completed at ________.

Question 37

Crossing over in prophase I and ________ in metaphase I increase the genetic variation from one generation to another.

Question 38

The failure of either homologous chromosomes to separate during meiosis I or sister chromatids to separate during meiosis II is called ________.

Question 39

One out of every 800 to 1000 infants born will have three copies of chromosome 21 (trisomy 21), a condition known as ________.

Question 40

The ________ are the 22 pairs of chromosomes not including the X and Y chromosomes.

Question 41

Complete the following table concerning mitosis and meiosis:

Question 42

During gamete formation at the end of telophase I, the ploidy of the daughter cells is ________, and each chromosome consists of ________ chromatid(s).

Question 43

DNA replication occurs in the ________ of the cell cycle.

Question 44

Suppose a researcher claims to be able to make a hybrid animal that is a cross between a goat and a horse. This animal has been termed "gorse." The normal diploid number for a goat is 60, and the normal diploid number for a horse is 62. Ignore the ethics here, and answer the following. Based on normal meiosis, a goat gamete (haploid) should have ________ chromosomes, whereas a horse gamete (haploid) should have ________ chromosomes. This means we would expect our hybrid gorse to contain a total of ________ chromosomes per cell. Let's assume our researcher beats the odds and that this hybrid "gorse" survives. Even if the hybrid survives, it is likely that it will be sterile. Referring to the above numbers, you can see that a problem is likely to occur when the hybrid produces its gametes. Explain what that problem will be.

Question 45

At the end of prophase II in meiosis, a human cell has ________ pairs of homologous chromosomes.

Question 46

Each cell contains two chromosomes with genes for the same traits; these chromosomes are called ________.

Question 47

Suppose that mitosis were used to produce the gametes. What unique problems would be encountered? Make a prediction about the future of humans as a species.

Question 48

A 42-year-old woman becomes pregnant. Her physician recommends amniocentesis (a test for fetal chromosomal disorders). When the results are analyzed by the laboratory, it is determined that the fetus has 47 chromosomes. Name and fully explain what caused this disorder. When the woman and her husband consult a genetic counselor, they are told that this problem is likely to have occurred in the woman's egg cells, not in her 50-year-old husband's sperm cells. Explain why.

Question 49

Explain two important sources of genetic variation in meiosis. Evolutionarily speaking, why do you think is it important that meiosis involves recombination of the genes?

Question 50

The condition in which there is only one representative of a particular chromosome in a cell is called ________.

Question 51

What are the results of nondisjunction, and why are these chromosome alterations so detrimental to an individual?

Question 52

Compare and contrast the processes of oogenesis and spermatogenesis.

Question 53

A baby is born with the genotype XYY. This sort of disorder is the result of nondisjunction during meiosis. In the case of the XYY genotype, can you be certain which parent had the nondisjunction in his or her gamete? Explain your answer.

Question 54

Eukaryotic cell division consists of interphase and cell division. Explain what happens in the three parts of interphase (G1, S, and G2).