Question 1

If the apical ectodermal ridge is surgically removed from an embryo, it will lose ________.

Accepted Answer

A)  positional information for limb-bud pattern formation 
B)  guidance signals needed for correct gastrulation 
C)  unequal cytokinesis of blastomeres 
D)  the developmental substrate for the kidneys 
A)  positional information for limb-bud pattern formation 
B)  guidance signals needed for correct gastrulation 
C)  unequal cytokinesis of blastomeres 
D)  the developmental substrate for the kidneys A

Question 2

At the moment of sperm penetration, human eggs ________.

Accepted Answer

A)  have used flagellar propulsion to move from the ovary to the oviduct 
B)  are still located within the ovary 
C)  have a paper-thin cell of calcium carbonate that prevents desiccation 
D)  are still surrounded by follicular cells 
A)  have used flagellar propulsion to move from the ovary to the oviduct 
B)  are still located within the ovary 
C)  have a paper-thin cell of calcium carbonate that prevents desiccation 
D)  are still surrounded by follicular cells D

Question 3

Which of the following is a result of gastrulation in animals?
I.The archenteron is formed.
II.The body axes are established.
III.The germ layers are formed.

Accepted Answer

A)  I 
B)  III 
C)  I and II 
D)  I, II, and III 
A)  I 
B)  III 
C)  I and II 
D)  I, II, and III D

Question 4

If an egg cell were treated with EDTA, a chemical that binds calcium and magnesium ions,

Accepted Answer

A)  the acrosomal reaction would be blocked. 
B)  the fusion of sperm and egg nuclei would be blocked. 
C)  the fast block to polyspermy would not occur. 
D)  the fertilization envelope would not form. 
A)  the acrosomal reaction would be blocked. 
B)  the fusion of sperm and egg nuclei would be blocked. 
C)  the fast block to polyspermy would not occur. 
D)  the fertilization envelope would not form.

Question 5

In an egg cell treated with a chemical that binds calcium and magnesium ions, the ________.

Accepted Answer

A)  acrosomal reaction would be blocked 
B)  fusion of sperm and egg nuclei would be blocked 
C)  fast block to polyspermy would not occur 
D)  fertilization envelope would not be formed 
A)  acrosomal reaction would be blocked 
B)  fusion of sperm and egg nuclei would be blocked 
C)  fast block to polyspermy would not occur 
D)  fertilization envelope would not be formed

Question 6

A reproductive difference between sea urchins and humans is ________.

Accepted Answer

A)  the sea urchin egg completes meiosis prior to fertilization, but meiosis in humans is completed after fertilization 
B)  sea urchin eggs and sperm are of equal size, but human eggs are much bigger than human sperm 
C)  sea urchins, but not humans, have a need to block polyspermy, because only in sea urchins can there be more than one source of sperm to fertilize the eggs 
D)  sea urchin zygotes get their mitochondria from the sperm, but human zygotes get their mitochondria from the egg 
A)  the sea urchin egg completes meiosis prior to fertilization, but meiosis in humans is completed after fertilization 
B)  sea urchin eggs and sperm are of equal size, but human eggs are much bigger than human sperm 
C)  sea urchins, but not humans, have a need to block polyspermy, because only in sea urchins can there be more than one source of sperm to fertilize the eggs 
D)  sea urchin zygotes get their mitochondria from the sperm, but human zygotes get their mitochondria from the egg

Question 7

The least amount of yolk would be found in the egg of a ________.

Accepted Answer

A)  bird 
B)  frog 
C)  eutherian mammal 
D)  reptile 
A)  bird 
B)  frog 
C)  eutherian mammal 
D)  reptile

Question 8

Thalidomide, now banned for use as a sedative during pregnancy, was used in the early 1960s by many women in their first trimester of pregnancy. Some of these women gave birth to children with limb and organ deformities, suggesting that the drug most likely influenced ________.

Accepted Answer

A)  early cleavage divisions 
B)  differentiation of bone tissue 
C)  morphogenesis 
D)  gastrulation 
A)  early cleavage divisions 
B)  differentiation of bone tissue 
C)  morphogenesis 
D)  gastrulation

Question 9

Uterine implantation due to enzymatic digestion of the endometrium is initiated by the ________.

Accepted Answer

A)  inner cell mass 
B)  endoderm 
C)  mesoderm 
D)  trophoblast 
A)  inner cell mass 
B)  endoderm 
C)  mesoderm 
D)  trophoblast

Question 10

Just prior to the onset of gastrulation in an embryo, the "organizer" cells are specified. If you were to experimentally block the specification of these cells, what would you expect the result to be in the developing embryo?

Accepted Answer

A)  There would be no effect on development. 
B)  Gastrulation would not occur, and normal development would cease. 
C)  The body axes would develop normally, but the embryo would not grow appendages. 
D)  The embryo would not develop an intestine, but all other organs and tissues would develop normally. 
A)  There would be no effect on development. 
B)  Gastrulation would not occur, and normal development would cease. 
C)  The body axes would develop normally, but the embryo would not grow appendages. 
D)  The embryo would not develop an intestine, but all other organs and tissues would develop normally.

Question 11

Changes in the shape of a cell usually involve a reorganization of the ________.

Accepted Answer

A)  nucleus 
B)  cytoskeleton 
C)  extracellular matrix 
D)  transport proteins 
A)  nucleus 
B)  cytoskeleton 
C)  extracellular matrix 
D)  transport proteins

Question 12

Which of the following is a correct description of the fate of the germ layers?

Accepted Answer

A)  The mesoderm gives rise to the notochord. 
B)  The endoderm gives rise to the hair follicles. 
C)  The ectoderm gives rise to the liver. 
D)  The mesoderm gives rise to the lungs. 
A)  The mesoderm gives rise to the notochord. 
B)  The endoderm gives rise to the hair follicles. 
C)  The ectoderm gives rise to the liver. 
D)  The mesoderm gives rise to the lungs.

Question 13

The term applied to a morphogenetic process whereby cells extend themselves, making the mass of the cells narrower and wider, is ________.

Accepted Answer

A)  convergent extension 
B)  induction 
C)  invagination 
D)  involution 
A)  convergent extension 
B)  induction 
C)  invagination 
D)  involution

Question 14

During metamorphosis, a tadpole's tail is reduced in size by the process of ________.

Accepted Answer

A)  regeneration 
B)  apoptosis 
C)  oxidative phosphorylation 
D)  redifferentiation 
A)  regeneration 
B)  apoptosis 
C)  oxidative phosphorylation 
D)  redifferentiation

Question 15

The primitive streak in a bird is the functional equivalent of ________.

Accepted Answer

A)  the lip of the blastopore in the frog 
B)  the archenteron in a frog 
C)  the notochord in a mammal 
D)  neural crest cells in a mammal 
A)  the lip of the blastopore in the frog 
B)  the archenteron in a frog 
C)  the notochord in a mammal 
D)  neural crest cells in a mammal

Question 16

As cleavage continues during frog development, the size of the blastomeres ________.

Accepted Answer

A)  increases as the number of the blastomeres decreases 
B)  increases as the number of the blastomeres increases 
C)  decreases as the number of the blastomeres increases 
D)  decreases as the number of the blastomeres decreases 
A)  increases as the number of the blastomeres decreases 
B)  increases as the number of the blastomeres increases 
C)  decreases as the number of the blastomeres increases 
D)  decreases as the number of the blastomeres decreases

Question 17

In some rare salamander species, all individuals are females. Reproduction relies on those females having access to sperm from males of another species. However, the resulting embryos receive no genetic contribution from the males. Why do you think sperm are necessary for reproduction?

Accepted Answer

A)  The sperm allow morphogenesis to proceed. 
B)  Sperm trigger egg activation. 
C)  Cell differentiation is initiated by the sperm. 
D)  Sperm are necessary to produce a diploid zygote. 
A)  The sperm allow morphogenesis to proceed. 
B)  Sperm trigger egg activation. 
C)  Cell differentiation is initiated by the sperm. 
D)  Sperm are necessary to produce a diploid zygote.

Question 18

The archenteron develops into

Accepted Answer

A)  the mesoderm. 
B)  the endoderm. 
C)  the placenta. 
D)  the lumen of the digestive tract. 
A)  the mesoderm. 
B)  the endoderm. 
C)  the placenta. 
D)  the lumen of the digestive tract.

Question 19

During frog development, the blastocoel ________.

Accepted Answer

A)  becomes the archenteron 
B)  gives rise to the endoderm 
C)  gives rise to the placenta 
D)  is replaced by the expanding archenteron 
A)  becomes the archenteron 
B)  gives rise to the endoderm 
C)  gives rise to the placenta 
D)  is replaced by the expanding archenteron

Question 20

The outer-to-inner sequence of tissue layers in a post-gastrulation vertebrate embryo is ________.

Accepted Answer

A)  endoderm → ectoderm → mesoderm 
B)  mesoderm → endoderm → ectoderm 
C)  ectoderm → mesoderm → endoderm 
D)  ectoderm → endoderm → mesoderm 
A)  endoderm → ectoderm → mesoderm 
B)  mesoderm → endoderm → ectoderm 
C)  ectoderm → mesoderm → endoderm 
D)  ectoderm → endoderm → mesoderm

Exam 47: Animal Development

If the apical ectodermal ridge is surgically removed from an embryo, it will lose ________.

At the moment of sperm penetration, human eggs ________.

Which of the following is a result of gastrulation in animals? I.The archenteron is formed. II.The body axes are established. III.The germ layers are formed.

If an egg cell were treated with EDTA, a chemical that binds calcium and magnesium ions,

In an egg cell treated with a chemical that binds calcium and magnesium ions, the ________.

A reproductive difference between sea urchins and humans is ________.

The least amount of yolk would be found in the egg of a ________.

Thalidomide, now banned for use as a sedative during pregnancy, was used in the early 1960s by many women in their first trimester of pregnancy. Some of these women gave birth to children with limb and organ deformities, suggesting that the drug most likely influenced ________.

Uterine implantation due to enzymatic digestion of the endometrium is initiated by the ________.

Just prior to the onset of gastrulation in an embryo, the "organizer" cells are specified. If you were to experimentally block the specification of these cells, what would you expect the result to be in the developing embryo?

Changes in the shape of a cell usually involve a reorganization of the ________.

Which of the following is a correct description of the fate of the germ layers?

The term applied to a morphogenetic process whereby cells extend themselves, making the mass of the cells narrower and wider, is ________.

During metamorphosis, a tadpole's tail is reduced in size by the process of ________.

The primitive streak in a bird is the functional equivalent of ________.

As cleavage continues during frog development, the size of the blastomeres ________.

In some rare salamander species, all individuals are females. Reproduction relies on those females having access to sperm from males of another species. However, the resulting embryos receive no genetic contribution from the males. Why do you think sperm are necessary for reproduction?

The archenteron develops into

During frog development, the blastocoel ________.

The outer-to-inner sequence of tissue layers in a post-gastrulation vertebrate embryo is ________.

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Vascular Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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