Question 1

For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes based on the independent assortment of chromosomes during meiosis?

Accepted Answer

A)  23 
B)  46 
C)  about 1,000 
D)  about 8 million

Question 2

How does natural selection apply to sexual reproduction as opposed to asexual reproduction?

Accepted Answer

A)  Sexual reproduction results in new gene combinations, some of which will have increased reproductive fitness. 
B)  Sexual reproduction results in more new mutations, some of which will be better adapted. 
C)  Sexual reproduction allows more offspring to be produced increasing odds of survival. 
D)  Sexual reproduction utilizes far less energy than asexual reproduction.

Question 3

Which of the following results when homologous chromosomes cross over in meiosis?

Accepted Answer

A)  Two sister chromatids get tangled, resulting in one re-sequencing its DNA. 
B)  Two sister chromatids exchange identical pieces of DNA. 
C)  Corresponding segments of non-sister chromatids are exchanged. 
D)  DNA repair machinery alters maternal alleles so they match paternal ones

Question 4

Many diploid organisms produce haploid gametes for reproduction. Which of the following best describes how the diploid number of chromosomes is restored in the offspring of these organisms?

Accepted Answer

A)  DNA replication creates homologous chromosomes 
B)  independent assortment in meiosis allows random combinations of chromosomes 
C)  synapsis during prophase of meiosis I creates random combinations of alleles 
D)  fertilization combines chromosomes from each parent into resulting zygote

Question 5

For the following question, 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
Cohesins at centromeres of sister chromatids breakdown.

Accepted Answer

A)  III 
B)  IV 
C)  V 
D)  VII

Question 6

Which of the following phrases defines the term genome?

Accepted Answer

A)  the complete set of an organism's polypeptides 
B)  the complete set of a species' polypeptides 
C)  The complete set of a species expressed traits 
D)  the complete set of an organism's genes and other DNA sequences

Question 7

Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question.  Which sample is consistent with a cell that has completed mitosis?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  Either I or II

Question 8

Which of the following explanations correctly describes a reproductive approach?

Accepted Answer

A)  During mitosis, DNA replication occurs twice to insure each daughter cell contains a full set of chromosomes. 
B)  Mitosis, followed by cytokinesis, produces daughter cells that are genetically different from the parent cell, thus insuring variation within the population. 
C)  In asexual reproduction, a single individual is the sole parent and passes copies of its genes to its offspring without the fusion of gametes. 
D)  Single-celled organisms can fuse their cells, to form new cells that are not identical to the parent cell.

Question 9

Which of the following statements about the human X chromosomes is correct?

Accepted Answer

A)  It is present in every gametic cell of males and females. 
B)  It is the smaller than other chromosomes 
C)  It carries genes that influence an individual's biological sex. 
D)  It is referred to as an autosome.

Question 10

Which of the following processes will most likely produce a human zygote with 45 chromosomes?

Accepted Answer

A)  an error during anaphase II while the sperm was produced 
B)  failure of the egg nucleus to fuse with the sperm nucleus 
C)  failure of an egg to complete meiosis II 
D)  incomplete cytokinesis after meiosis I in sperm production

Question 11

Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question.  Which sample is consistent with a cell that is entering mitosis?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  Either I or II

Question 12

Which of the following statements describes the chromosomal makeup of each daughter cell after telophase of meiosis I?

Accepted Answer

A)  The cells are diploid, and the chromosomes are each composed of a single chromatid. 
B)  The cells are diploid, and the chromosomes are each composed of two chromatids. 
C)  The cells are haploid, and the chromosomes are each composed of a single chromatid. 
D)  The cells are haploid, and the chromosomes are each composed of two chromatids.

Question 13

A human cell containing 22 autosomes and a Y chromosome is ________.

Accepted Answer

A)  a sperm 
B)  an egg 
C)  a zygote 
D)  a somatic cell of a male

Question 14

Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The drawings in the figure below represent the chromosomes. Refer to the drawings and answer the following question(s).  Which diagram represents anaphase I of meiosis?

Accepted Answer

A)  I 
B)  II 
C)  IV 
D)  V

Question 15

In a human karyotype, chromosomes are arranged in 23 pairs. If one of the autosomal pairs is examined, which of the following characteristics will the two chromosomes of the pair have in common?

Accepted Answer

A)  length and DNA sequence 
B)  alleles and centromere position 
C)  loci and staining pattern 
D)  X-like shape and alignment on the metaphase plate

Question 16

A cell has completed meiosis I and the first cytokinesis, and is just beginning meiosis II. Which of the following statements describes its genetic contents?

Accepted Answer

A)  It has half the amount of DNA as the cell that began meiosis. 
B)  It has twice the DNA of the cell that began meiosis. 
C)  It has one-fourth the DNA and one-half the chromosomes as the cell that began meiosis. 
D)  It is genetically identical to the other cells produced by this cytokinesis.

Question 17

Which of the following processes occur during meiosis but not mitosis?

Accepted Answer

A)  Haploid cells fuse to form diploid cells. 
B)  Haploid cells multiply into more haploid cells. 
C)  Diploid cells form haploid cells. 
D)  A diploid cell combines with a haploid cell.

Question 18

If we continue to follow the cell lineage from question 4, then the DNA content of a single cell at metaphase of meiosis II will be ________.

Accepted Answer

A)  0.25x 
B)  0.5x 
C)  x 
D)  2x

Question 19

The two homologs of a pair move toward opposite poles of dividing cell during ________.

Accepted Answer

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

Question 20

Meiosis II is similar to mitosis in that ________.

Accepted Answer

A)  sister chromatids separate during anaphase 
B)  DNA replicates before the division 
C)  the daughter cells are diploid 
D)  homologous chromosomes synapse

Exam 13: Sexual Life Cycles and Meiosis