Download Chapter 18: Human Development and Birth

Chapter 18: Human Development and Birth
1.
A)
B)
C)
D)
Ans:
Embryonic development
refers to the first two weeks.
refers to week three to month two.
refers to months three to nine.
is described by all of these characteristics.
B
2.
A)
B)
C)
D)
Ans:
Cleavage
is cell division.
is mitosis.
occurs immediately after fertilization.
is described by all of these characteristics.
D
3.
A)
B)
C)
D)
Ans:
Morphogenesis refers to
increase of size.
shaping of the embryo.
cells having a specific function.
all of these.
B
4.
A)
B)
C)
D)
Ans:
What important event occurs in the second week of development?
Cell division begins.
Embryonic disk is formed.
Implanting begins.
Both choices B and C are correct.
D
5.
A)
B)
C)
D)
Ans:
During the fifth month
all organ systems have appeared.
ossification begins.
eight week.
mother begins to feel movement.
D
6.
A)
B)
C)
D)
Ans:
During the eighth week
all organ systems have appeared.
ossification begins.
eight week.
mother begins to feel movement.
A
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7.
A)
B)
C)
D)
Ans:
During the third month
all organ systems have appeared.
ossification begins.
eight week.
mother begins to feel movement.
B
8.
A)
B)
C)
D)
Ans:
During the fourth week
all organ systems have appeared.
ossification begins.
eight week.
mother begins to feel movement.
C
9.
A)
B)
C)
D)
Ans:
At the placenta,
oxygen enters the fetal circulation.
nutrients enter the fetal circulation.
nitrogenous wastes enter maternal circulation.
all of these events occur.
D
10.
A)
B)
C)
D)
Ans:
The placenta is composed of
chorionic villi.
uterine tissue.
fetal tissue.
all of these.
D
11.
A)
B)
C)
D)
Ans:
The umbilical cord contains
the fetal intestine.
blood vessels.
only muscle tissue.
the fetal intestine and muscle tissue.
B
12.
A)
B)
C)
Ans:
During stage one of parturtion
placenta is delivered.
birth.
cervix dilates.
C
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13.
A)
B)
C)
Ans:
During stage two of parturtion
placenta is delivered.
birth.
cervix dilates.
B
14.
A)
B)
C)
Ans:
During stage three of parturtion
placenta is delivered.
birth.
cervix dilates.
A
15.
A)
B)
C)
D)
E)
Ans:
Which causes uterine contractions?
prostaglandins
oxytocin
HCG
prostaglandins and oxytocin
all of these
D
16. State the process of development.
Ans: See text
17. List the events of embryonic and fetal development.
Ans: See text.
18. Discuss the stages of birth.
Ans: See text.
19. By the third week of embryonic life, what organs are developed? By what week are all
of the major organs developed?
Ans: By the third week the nervous system is starting to develop. By eight weeks all major
systems are established.
20. Distinguish between ovulation, fertilization, and pregnancy.
Ans: Ovulation is the release of an egg from the ovary, fertilization is the fusion of an egg
nucleus and a sperm nucleus, and pregnancy is the implantation of a developing embryo
in the uterine lining.
21. List the embryonic membranes and explain their functions.
Ans: The extraembryonic membranes are the amnion, which provides a fluid environment for
the development of the embryo and fetus; the yolk sac, which is the first site of red
blood cell production; the allantois, which contributes to the circulatory system; and the
chorion, which becomes part of the placenta.
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22. Distinguish between morphogenesis and differentiation.
Ans: Morphogenesis refers to shaping of the embryo and involves the movement of cells.
Differentiation occurs when a cell takes on a specific structure and function.
23. Compare and contrast cleavage and growth.
Ans: Cleavage occurs in a developing zygote whereas growth occurs in an embryo. During
cleavage, a zygote increases in cell number, but does not increase in size. A developing
embryo increases in both cell number and size.
24. List and describe three conditions that affect premature babies.
Ans: The text provides descriptions of six conditions that commonly affect premature babies.
These conditions are respiratory distress syndrome, retinopathy of prematurity,
intracranial hemorrhage, jaundice, infections, and circulatory disorders.
25. What is a breech birth and why may it necessitate a cesarean section delivery?
Ans: A breech birth occurs when the fetus' rump rather than its head is directed at the cervix.
It is difficult for the cervix to expand enough to allow for a breech birth and as a result,
the baby may have to be delivered by cesarean section.
26.
A)
B)
C)
D)
Ans:
Which is the last stage in pre-embroyonic development?
blastocyst
cleavage
fertilization
morula
A
27.
A)
B)
C)
D)
Ans:
From which primary germ layer do both the skeletal and muscular systems develop?
ectoderm
endoderm
mesoderm
None of these choices are correct for both systems.
C
28.
A)
B)
C)
D)
Ans:
A typical pregnancy test detects the pressure of
fetal hemoglobin.
estrogen.
HCG.
a corpus luteum.
C
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