Which sample(s) might represent a zygote?
A) I
B) II
C) III
D) either I or II
E) either II or III

I

A certain female's number 12 chromosomes both have the blue gene and number 19
chromosomes both have the long gene. As cells in her ovaries undergo meiosis, her resulting
eggs (ova) may have which of the following?
A) either two number 12 chromosomes with blue genes or two with orange genes
B) either two number 19 chromosomes with long genes or two with short genes
C) either one blue or one orange gene in addition to either one long or one short gene
D) one chromosome 12 with one blue gene and one chromosome 19 with one long gene

one chromosome 12 with one blue gene and one chromosome 19 with one long gene

If a female of this species has one chromosome 12 with a blue gene and another chromosome
12 with an orange gene, and has both number 19 chromosomes with short genes, she will
produce which of the following egg types?
A) only blue short gene eggs
B) only orange short gene eggs
C) one-half blue short and one-half orange short gene eggs
D) three-fourths blue long and one-fourth orange short gene eggs
E) three-fourths blue short and one-fourth orange short gene eggs

one-half blue short and one-half orange short gene eggs

A female with a paternal set of one orange and one long gene chromosome and a maternal
set comprised of one blue and one short gene chromosome is expected to produce which of the
following types of eggs after meiosis?
A) All eggs will have maternal types of gene combinations.
B) All eggs will have paternal types of gene combinations.
C) Half the eggs will have maternal and half will have paternal combinations.
D) Each egg has a one-fourth chance of having either blue long, blue short, orange long, or
orange short combinations.
E) Each egg has a three-fourths chance of having blue long, one-fourth blue short, three-fourths
orange long, or one-fourth orange short combinations.

Each egg has a one-fourth chance of having either blue long, blue short, orange long, or
orange short combinations.

Because the rotifers develop from eggs, but asexually, what can you predict?
A) The eggs and the zygotes are all haploid.
B) The animals are all hermaphrodites.
C) Although asexual, both males and females are found in nature.
D) All males can produce eggs.
E) No males can be found.

No males can be found

How is natural selection related to sexual reproduction as opposed to asexual reproduction?
A) Sexual reproduction results in many new gene combinations, some of which will lead to
differential reproduction.
B) Sexual reproduction results in the most appropriate and healthiest balance of two sexes in a
population.
C) Sexual reproduction results in the greatest number of new mutations.
D) Sexual reproduction allows the greatest number of offspring to be produced.
E) Sexual reproduction utilizes far less energy than 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) a sperm.
B) an egg.
C) a zygote.
D) a somatic cell of a male.
E) a somatic cell of a female.

a sperm

Homologous chromosomes move toward opposite poles of a dividing cell during
A) mitosis.
B) meiosis I.
C) meiosis II.
D) fertilization.
E) binary fission

meiosis I.

If the DNA content of a diploid cell in the G1 phase of the cell cycle is x, then the DNA
content of the same cell at metaphase of meiosis I would be
A) 0.25x.
B) 0.5x.
C) x.
D) 2x.
E) 4x.

2x

If we continued to follow the cell lineage from question 3, then the DNA content of a single
cell at metaphase of meiosis II would be
A) 0.25x.
B) 0.5x.
C) x.
D) 2x.
E) 4x

x

How many different combinations of maternal and paternal chromosomes can be packaged in
gametes made by an organism with a diploid number of 8 (2n = 8)?
A) 2
B) 4
C) 8
D) 16
E) 32

16