Chapter 28

Question 1

Sperm and ova are similar in terms of ________:

a. size
b. quantity produced per year
c. chromosome number
d. flagellar motility

Answer 1

C. Chromosome number

Question 2

Although the male ejaculate contains hundreds of millions of sperm, ________:

a. most do not reach the oocyte
b. most are destroyed by the alkaline environment of the uterus
c. it takes millions to penetrate the outer layers of the oocyte
d. most are destroyed by capacitation

Answer 2

Most do not reach the oocyte

Question 3

As sperm first reach the oocyte, they will contact the ________:

a. acrosome
b. corona radiata
c. sperm-binding receptors
d. zona pellucida

Answer 3

B. Corona radiata

Question 4

Fusion of pronuclei occurs during ________:

a. spermatogenesis
b. ovulation
c. fertilization
d. capacitation

Answer 4

Fertilization

Question 5

Sperm must first complete ________ to enable the fertilization of an oocyte

a. capacitation
b. the acrosomal reaction
c. the cortical reaction
d. the fast block

Answer 5

A. Capacitation

Question 6

Cleavage produces daughter cells called ________.

a. trophoblasts
b. blastocysts
c. morulae
d. blastomeres

Answer 6

d. blastomeres

Question 7

The conceptus, upon reaching the uterus, first ________.

a. implants
b. divides
c. disintegrates
d. hatches

Answer 7

B. divides

Question 8

The inner cell mass of the blastocyst is destined to
become the \_\_\_\_\_\_\_\_.
a. embryo
b. trophoblast
c. chorionic villi
d. placenta

Answer 8

a. embryo

Question 9

Which primary germ layer gave rise to the cells that
eventually became the central nervous system?
a. endoderm
b. ectoderm
c. acrosome
d. mesoderm

Answer 9

b. ectoderm

Question 10

. What would happen if the trophoblast did not secrete
hCG upon implantation of the blastocyst?
a. The cells would not continue to divide.
b. The corpus luteum would continue to produce
progesterone and estrogen.
c. Menses would flush the blastocyst out of the
uterus.
d. The uterine mucosa would not envelop the
blastocyst

Answer 10

c. Menses would flush the blastocyst out of the

uterus.

Question 11

During what process does the amnion envelop the
embryo?
a. embryonic folding
b. gastrulation
c. implantation
d. organogenesis

Answer 11

a. embyonic folding

Question 12

The placenta is formed from ________.
a. the embryo’s mesenchymal cells
b. the mother’s endometrium only
c. the mother’s endometrium and the embryo’s
chorionic membrane
d. the mother’s endometrium and the embryo’s
umbilical cord

Answer 12

c. the mother’s endometrium and the embryo’s

chorionic membrane

Question 13

The foramen ovale causes the fetal circulatory system
to bypass the \_\_\_\_\_\_\_\_.
a. liver
b. lungs
c. kidneys
d. gonads

Answer 13

b. lungs

Question 14

What happens to the urine excreted by the fetus when
the kidneys begin to function?
a. The umbilical cord carries it to the placenta for
removal.
b. The endometrium absorbs it.
c. It adds to the amniotic fluid.
d. It is turned into meconium.

Answer 14

c. It adds to the amniotic fluid

Question 15

During weeks 9–12 of fetal development, ________.
a. bone marrow begins to assume erythrocyte
production
b. meconium begins to accumulate in the intestines
c. surfactant production begins in the fetal lungs
d. the spinal cord begins to be myelinated

Answer 15

a. bone marrow begins to assume erythrocyte

production

Question 16

Progesterone secreted by the placenta suppresses
________ to prevent maturation of ovarian follicles.
a. LH and estrogen
b. hCG and FSH
c. FSH and LH
d. estrogen and hCG

Answer 16

c. FSH and LH

Question 17

Which of the following is a possible culprit of
“morning sickness”?
a. increased minute respiration
b. decreased intestinal peristalsis
c. decreased aldosterone secretion
d. increased blood volume

Answer 17

b. decreased intestinal peristalsis

Question 18

How does the decrease in progesterone at the last
weeks of pregnancy help to bring on labor?
a. stimulating FSH production
b. decreasing the levels of estrogens
c. dilating the cervix
d. decreasing the inhibition of uterine contractility

Answer 18

d. decreasing the inhibition of uterine contractility

Question 19

Which of these fetal presentations is the easiest for
vaginal birth?
a. complete breech
b. vertex occiput anterior
c. frank breech
d. vertex occiput posterior

Answer 19

b. vertex occiput anterior

Question 20

Which of these shunts exists between the right and left
atria?
a. foramen ovale
b. ductus venosus
c. ductus arteriosis
d. foramen venosus

Answer 20

a. foramen ovale

Question 21

Why is brown fat important?
a. It is the newborn’s primary source of insulation.
b. It can be broken down to generate heat for
thermoregulation.
c. It can be broken down for energy between
feedings.
d. It can be converted to white fat

Answer 21

b. It can be broken down to generate heat for

thermoregulation

Question 22

Constriction of umbilical blood vessels during vaginal birth ________.

a. causes respiratory alkalosis
b. inhibits the respiratory center in the brain
c. elevates carbon dioxide levels in the blood
d. both a and b

Answer 22

c. elevates carbon dioxide levels in the blood

Question 23

Alveoli are connected to the lactiferous sinuses by ________.

a. lactocytes
b. lactiferous ducts
c. nipple pores
d. lobules

Answer 23

B. lactiferous ducts

Question 24

How is colostrum most important to a newborn?

a. It helps boost the newborn’s immune system.
b. It provides much needed fat.
c. It satisfies the newborn’s thirst.
d. It satisfies the infant’s appetite

Answer 24

a. It helps boost the newborn’s immune system

Question 25

Mature breast milk ________. a. has more sodium than cow’s milk b. has more calcium than cow’s milk c. has more protein than cow’s milk d. has more fat than cow’s milk

Answer 25

d. has more fat than cow’s milk

Question 26

Marfan syndrome is inherited in an autosomal dominant pattern. Which of the following is true? a. Female offspring are more likely to be carriers of the disease. b. Male offspring are more likely to inherit the disease. c. Male and female offspring have the same likelihood of inheriting the disease. d. Female offspring are more likely to inherit the disease

Answer 26

Male and female offspring have the same | likelihood of inheriting the disease.

Question 27

In addition to codominance, the ABO blood group antigens are also an example of ________. a. incomplete dominance b. X-linked recessive inheritance c. multiple alleles d. recessive lethal inheritance

Answer 27

c. multiple alleles

Question 28

. Zoe has cystic fibrosis. Which of the following is the most likely explanation? a. Zoe probably inherited one faulty allele from her father, who is a carrier, and one normal allele from her mother. b. Zoe probably inherited one faulty allele from her mother, who must also have cystic fibrosis, and one normal allele from her father. c. Zoe must have inherited faulty alleles from both parents, both of whom must also have cystic fibrosis. d. Zoe must have inherited faulty alleles from both parents, both of whom are carriers

Answer 28

Zoe must have inherited faulty alleles from both | parents, both of whom are carriers