CHAPTER 50—ANIMAL DEVELOPMENT
MULTIPLE CHOICE
1. Uterine contractions are most likely an example of
a.
a unique human reproductive phenomena.
b.
negative feedback.
c.
positive feedback.
d.
programmed events.
e.
positive feedback and programmed events.
2. The human brain develops into a unique organ based on which of the following characteristics?
a.
Integrative capacity.
b.
Degree of complexity.
c.
Unique embryonic pathways lead to brain development.
d.
Integrative capacity and degree of complexity.
e.
Integrative capacity, degree of complexity, and unique embryonic pathways lead to brain
development.
3. Morphology refers to the ____ of an organism.
a.
reproductive ability
b.
appearance
c.
differentiation
d.
lifespan
e.
movement
4. At the cellular level, the development of an animal from a fertilized egg involves
a.
cell division by meiosis.
b.
cell division by mitosis.
c.
cell division by differentiation
d.
cell division by morphogenesis.
e.
cell division by cloning.
5. Before the genes of a zygote become active, the stages of animal development are directed by
a.
the environment.
b.
the cytoplasmic determinants of the egg.
c.
the cytoplasmic determinants of the sperm.
d.
the cytoplasmic determinants of the egg and the sperm.
e.
the nucleus.
6. How does the amount of yolk relate to the nourishment of the organism?
a.
An egg with a small amount of yolk contains all of the nutrients for the embryo’s
development.
b.
An egg with a large amount of yolk contains all of the nutrients for the embryo’s
development.
c.
An egg lacking yolk contains all of the nutrients for the embryo’s development.
d.
There is no relationship between the amount of yolk and the nourishment of the organism.
e.
All animals have the same amount of yolk and provide the same amount of nourishment.
7. Eggs from which of the following organisms would contain the lowest percentage of yolk?
a.
birds
b.
humans
c.
insects
d.
reptiles
e.
moths
8. Which term represents the unequal distribution of yolk in an egg?
a.
cleavage
b.
gastrulation
c.
involution
d.
neurulation
e.
polarity
9. During mitotic cleavage
a.
no cell division occurs and the mass does not increase.
b.
no cell division occurs and the mass does increase.
c.
cell division occurs and the mass does not increase.
d.
cell division occurs and the mass does increase.
e.
the cell is in a dormant stage.
10. Put the following developmental processes in the correct order.
a.
cleavage − gastrulation − organogenesis
b.
cleavage − organogenesis − gastrulation
c.
gastrulation − cleavage − organogenesis
d.
gastrulation − organogenesis − cleavage
e.
organogenesis − cleavage − gastrulation
11. Place the three primary cell layers of an embryo in order from superficial to deep.
a.
ectoderm − endoderm − mesoderm
b.
ectoderm − mesoderm − endoderm
c.
endoderm − ectoderm − mesoderm
d.
endoderm − mesoderm − ectoderm
e.
mesoderm − ectoderm − endoderm
12. Put these developmental stages in the proper order.
a.
blastula − gastrula − morula
b.
blastula − morula − gastrula
c.
gastrula − blastula − morula
d.
morula − blastula − gastrula
e.
morula − gastrula − blastula
13. Muscles originate from
a.
ectoderm.
b.
endoderm.
c.
mesoderm.
d.
ectoderm and endoderm.
e.
ectoderm and mesoderm.
14. Which group of adult tissues is derived from mesoderm?
a.
lining of digestive tract, liver, pancreas
b.
muscles, bones, cartilage
c.
skin, brain, retina
d.
skin, liver, pancreas
e.
lining of respiratory tract, thyroid gland, urinary bladder
15. Lining of mouth and anus originate from _____, while lining of the respiratory tract originate from
______.
a.
ectoderm; endoderm
b.
ectoderm; mesoderm
c.
endoderm; ectoderm
d.
endoderm; mesoderm
e.
mesoderm; endoderm
16. Evidence that differentiating cells all contain complete genomes of an organism is provided by
a.
comparison of frog and sea urchin development.
b.
Some cells remain totipontent
c.
totipotent cells give rise to multipotent cells
d.
multipotent cells can give rise to pluripotent cells
e.
the successful cloning of a sheep – Dolly
17. Cleavage divisions proceed at approximately the same rate in the embryo of _______, reflecting
uniform distribution of yolk.
a.
bird
b.
human
c.
sea urchin
d.
frog
e.
sea urchin and human
18. In which animal’s development does the rotation of the gray crescent play a major role?
a.
bird
b.
frog
c.
grasshopper
d.
human
e.
sea urchin
19. Which of the following organisms has a pattern of gastrulation that is the most similar to humans?
a.
amphibians
b.
birds
c.
drosophila
d.
sea urchin
e.
zebra fish
20. Which structure in the development of the amphibian is equivalent to the primitive knot in bird
development?
a.
the archenteron
b.
the dorsal lip of the blastopore
c.
the ventral lip of the blastopore
d.
ectoderm
e.
endoderm
21. The extraembryonic membrane that secretes fluid around the developing embryo is the
a.
allantois.
b.
amnion.
c.
chorion.
d.
yolk sac.
e.
both the allantois and the yolk sac.
22. The chorion is produced from which primary tissue layer(s)?
a.
ectoderm and endoderm
b.
ectoderm and mesoderm
c.
endoderm and mesoderm
d.
ectoderm only
e.
endoderm only
23. Which of the following is a defining feature of vertebrate nervous system development?
a.
Oraganogenesis
b.
Ectoderm develops into organs
c.
Ectoderm and endoderm develop into organs
d.
Ectoderm, endoderm and mesoderm develop into organs
e.
Neural crest
24. Which of the following structures of the eye is matched appropriately with its developmental material?
a.
cornea − ectoderm
b.
cornea − crystallin
c.
lens − optic cup
d.
retina − crystallin
e.
retina − ectoderm
25. In response to induction by the optic vesicle,
a.
genes coding for crystallin and keratin are activated.
b.
genes coding for only crystallin are activated.
c.
genes coding for only keratin are activated.
d.
genes coding for crystalline and keratin are not activated.
e.
apoptosis occurs.
26. Tissues present during development of an organ but not found in the fully formed organ are removed
by
a.
apoptosis only.
b.
programed cell death only.
c.
molecular signals received by receptors on marked cells only.
d.
apoptosis and programed cell death.
e.
apoptosis, programed cell death, molecular signals received by receptors on marked cells.
27. Gestation takes approximately ____ days in humans.
a.
279
b.
266
c.
231
d.
206
e.
178
28. At what point in development is a human embryo considered to be a fetus?
a.
2 weeks
b.
4 weeks
c.
8 weeks
d.
10 weeks
e.
12 weeks
29. In the postpartum female,
a.
oxytocin stimulates the production and secretion of milk.
b.
oxytocin stimulates the production of milk and prolactin stimulates the secretion of milk.
c.
prolactin stimulates the production and secretion of milk.
d.
prolactin stimulates the production of milk and oxytocin stimulates the secretion of milk.
e.
estrogen and progesterone are directly responsible for the production and secretion of
milk.
30. What determines the development of male or female sex organs in the human embryo?
a.
environmental factors
b.
genes on the X chromosome
c.
genes on the Y chromosome
d.
genes on both the X and Y chromosomes
e.
neither the X or the Y chromosomes
31. When the SRY gene of the Y chromosome becomes active (around 7 weeks),
a.
the Müllerian and Wolffian ducts both develop into male reproductive structures.
b.
the Müllerian ducts develop into male reproductive structures and the Wolffian ducts
disappear.
c.
the Müllerian ducts disappear and the Wolffian ducts develop into male reproductive
structures.
d.
the Müllerian and Wolffian ducts both disappear.
e.
the Müllerian and Wolffian ducts both develop into female reproductive structures.
32. Which of the following cells stop dividing once fully formed?
a.
bone cells
b.
cheek cells
c.
liver cells
d.
muscle cells
e.
nerve cells in the brain
33. During differentiation, organs develop with different numbers of cells because
a.
the cell adhesion molecules are present in some tissues.
b.
the cells migrate.
c.
the formation of myosin begins.
d.
the length of interphase varies.
e.
the microtubules rearrange.
34. Fate maps have been produced for which of the following
a.
humans only
b.
chickens only
c.
Xenopus only
d.
chickens, Xenopus, and Drosophila
e.
humans, chickens, Xenopus, and Drosophila
35. Individuals with a mutation in the SRY gene develop into
a.
males with YY combination of sex chromosomes
b.
females with YY combination of sex chromosomes
c.
females with XY combination of sex chromosomes
d.
hermaphrodites
e.
they do not complete development
36. Experiments on selective adhesion demonstrated
a.
ectoderm cells have positive affinity for
mesoderm cells but negative affinity for
endoderm cells
d.
ectoderm cells have positive affinity for
both endoderm and mesoderm cells
b.
ectoderm cells have negative affinity for
mesoderm cells but positive affinity for
endoderm cells
e.
endoderm cells have positive affinity for
both ectoderm and mesoderm cells
c.
endoderm cells have positive affinity for
mesoderm cells but negative affinity for
ectoderm cells
37. When a dorsal lip from a newt is attached to the ventral side of another embryo, it results in
a.
two separate newts.
b.
two attached newts.
c.
survival of only the original newt.
d.
death of the newt.
e.
no observable result.
38. Which of the following statements is FALSE?
a.
The Y chromosome determines the development of testes in humans.
b.
Avian sex determination is chromosomal.
c.
The sex of a developing cell is entirely determined from hormonal signals outside the cell.
d.
Bird sex determination system is opposite of that found in humans.
e.
Birds have a ZW sex determination system.
39. Which of the following statements regarding polarity in an egg is INCORRECT?
a.
The animal pole forms the anterior end of the animal.
b.
The vegetal pole forms the posterior end of the animal.
c.
The animal pole forms the animal’s gut.
d.
The vegetal pole forms internal structures.
e.
Polarity relates to development of body axes.
40. Which of these structures is NOT derived from the neural crest?
a.
bones of inner ear
b.
cartilage of the face
c.
cranial nerves
d.
teeth
e.
muscles
41. Which of the following structures is NOT derived from the pharyngeal arches?
a.
face
b.
mouth
c.
neck
d.
nasal cavities
e.
shoulder blades
1011
42. The information that directs the development of the fertilized egg is present in all of the following
EXCEPT
a.
information in egg nucleus
b.
information in sperm nucleus
c.
mRNA in egg cytoplasm
d.
proteins in egg cytoplasm
e.
sperm cytoplasm
43. Apoptosis is responsible for all of the following EXCEPT
a.
the ability of newly born kittens to open their eyelids.
b.
the generation of body axes.
c.
destruction of the tadpole’s tail.
d.
destruction of some larval tissue in a developing butterfly.
e.
removal of webbing between human fingers.
44. Whole-cell movements involve the coordinated activity of
a.
microtubules.
b.
microfilaments.
c.
blastomeres.
d.
microtubules and microfilaments.
e.
microtubules and microfilaments and blastomeres.
MATCHING
Match the terms to the appropriate definitions.
a.
A fluid filled cavity within the blastomere
b.
The stage in which an embryo has three tissue layers
c.
Solid ball of blastomeres
d.
An opening that eventually becomes the anus or mouth
e.
Process that involves increases in number of cells, but not mass
f.
Early stage in formation of the nervous system
g.
Second stage of cleavage; blastomeres are surrounding a hollow cavity
45. blastocoel
46. blastopore
47. blastula
48. cleavage
49. gastrula
50. morula
51. neural plate
1012
Put the following mechanisms of development in the order they occur.
a.
Cell movements
b.
Determination
c.
Differentiation
d.
Induction
e.
Mitotic cell divisions
f.
Selective cell adhesions
52. first mechanism
53. second mechanism
54. third mechanism
55. fourth mechanism
56. fifth mechanism
57. sixth mechanism
Match the scientific terms with the appropriate definitions below.
a.
Undifferentiated muscle cells
b.
Pigmented layer of cytoplasm opposite from point of entry of sperm
c.
Rounded layer of cells at the surface of yolk in birds
d.
Solid rod of tissue that is involved in neurulation
e.
Fingerlike extensions into the endometrium
1013
58. gray crescent
59. blastodisc
60. notochord
61. crystalline
62. apoptosis
63. chorionic villi
64. induction
65. myoblast
1014
Labeling
Label each of the lettered areas with one of the developmental terms from the word bank below.
66. cleavage
67. development into adult
68. fertilization
69. gastrulation
70. organogenesis
71. sexual reproduction
Labeling
Label the diagram of extraembryonic membranes with the terms listed below.
72. allantois
73. amnion
74. amniotic cavity
75. embryo
76. chorion
77. yolk sac
MODIFIED TRUE/FALSE
If the statement is true, answer “T“. If the statement is false, answer “F” and make it correct by
changing the underlined word(s) and writing the correct word(s) in the answer blank(s).
78. An egg’s polarity determines the orientation of body axes.
79. The material in the gray crescent of a frog embryo is necessary for normal development.
80. In terrestrial animals, such as the bird, the embryo is exposed to a dry environment while in the egg.
81. The symmetrical pattern of yolk distribution in a sea urchin represents the beginnings of radial
symmetry.
82. Cleavage in a frog embryo takes place more quickly in the vegetal half.
83. The nervous system structures are derived from ectoderm.
84. Cells that undergo apoptosis are essential to the organism throughout their life.
85. Chorionic villi eventually become the placenta.
86. The process of apoptosis can remove structures such as mammary tissue in male mammals.
87. The initiation of childbirth is a relatively simple process that has been fully explained.
SHORT ANSWER
88. How does the location of the yolk in an egg influence its development?
89. How do stem cell studies relate to the process of cell differentiation in an embryo?
90. How can your knowledge of neural tube formation provide you with an insight into congenital diseases
that involve incomplete neural tube closure?
91. Why could an ultrasound performed at four weeks be unable to determine the sex of a developing
fetus?
92. How do we know that differentiation produces specialized cells without the loss of genes?
ESSAY
93. Describe how the selective adhesion property of cells was proven.
94. Fate mapping is currently used to determine the embryonic origin of tissues in an adult. What possible
applications do you see for this procedure in the future?
95. What is the immune function of the placenta in human and marsupial embryo development?