Question 1

An embryo with meroblastic cleavage, extraembryonic membranes, and a primitive streak must be that of

Accepted Answer

A)  an insect. 
B)  a fish. 
C)  an amphibian. 
D)  a bird. 
E)  a sea urchin. 
A)  an insect. 
B)  a fish. 
C)  an amphibian. 
D)  a bird. 
E)  a sea urchin.

Question 2

The pattern of embryonic development in which only the cells lacking yolk subsequently undergo cleavage is called

Accepted Answer

A)  arcadian development, which is typical of insects. 
B)  holoblastic development, which is typical of marsupial mammals. 
C)  meroblastic development, which is typical of humans. 
D)  holoblastic development, which is typical of amphibians. 
E)  meroblastic development, which is typical of birds. 
A)  arcadian development, which is typical of insects. 
B)  holoblastic development, which is typical of marsupial mammals. 
C)  meroblastic development, which is typical of humans. 
D)  holoblastic development, which is typical of amphibians. 
E)  meroblastic development, which is typical of birds.

Question 3

An open space within the gastrula is the

Accepted Answer

A)  ectoderm. 
B)  mesoderm. 
C)  archenteron. 
D)  endoderm. 
E)  neural crest cells. 
A)  ectoderm. 
B)  mesoderm. 
C)  archenteron. 
D)  endoderm. 
E)  neural crest cells.

Question 4

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. 
E)  nucleolus. 
A)  nucleus. 
B)  cytoskeleton. 
C)  extracellular matrix. 
D)  transport proteins. 
E)  nucleolus.

Question 5

Which of the following is a correct description of an anatomical relationship?

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 6

Use the following information to answer the next few questions.
In a study of the development of frog embryos, researchers stained several early gastrulas with vital dyes and noted the locations of the dyes after gastrulation. The results are shown in the following table.
  
-The ectoderm should give rise to tissues containing

Accepted Answer

A)  yellow and purple colors. 
B)  purple and green colors. 
C)  green and red colors. 
D)  red and blue colors. 
E)  red and yellow colors. 
A)  yellow and purple colors. 
B)  purple and green colors. 
C)  green and red colors. 
D)  red and blue colors. 
E)  red and yellow colors.

Question 7

Fertilization of an egg without activation is most like

Accepted Answer

A)  placing the key in the ignition of a car but not starting the engine. 
B)  resting during halftime of a basketball game. 
C)  preparing a pie from scratch and baking it in the oven. 
D)  walking to the cafeteria and eating lunch. 
E)  dropping a rock off a cliff and watching it land in the valley below. 
A)  placing the key in the ignition of a car but not starting the engine. 
B)  resting during halftime of a basketball game. 
C)  preparing a pie from scratch and baking it in the oven. 
D)  walking to the cafeteria and eating lunch. 
E)  dropping a rock off a cliff and watching it land in the valley below.

Question 8

Cells move to new positions as an embryo establishes its three germ tissue layers during

Accepted Answer

A)  determination. 
B)  cleavage. 
C)  fertilization. 
D)  induction. 
E)  gastrulation. 
A)  determination. 
B)  cleavage. 
C)  fertilization. 
D)  induction. 
E)  gastrulation.

Question 9

During fertilization, the acrosomal contents

Accepted Answer

A)  block polyspermy. 
B)  help propel more sperm toward the egg. 
C)  digest the protective jelly coat on the surface of the egg. 
D)  nourish the mitochondria of the sperm. 
E)  trigger the completion of meiosis by the sperm. 
A)  block polyspermy. 
B)  help propel more sperm toward the egg. 
C)  digest the protective jelly coat on the surface of the egg. 
D)  nourish the mitochondria of the sperm. 
E)  trigger the completion of meiosis by the sperm.

Question 10

Human trophoblasts

Accepted Answer

A)  form the inner cell mass. 
B)  form from ectoderm. 
C)  are the precursors of the mesoderm. 
D)  are of embryonic origin and function in embryo nutrition. 
E)  are of maternal origin and function in embryo gas exchange. 
A)  form the inner cell mass. 
B)  form from ectoderm. 
C)  are the precursors of the mesoderm. 
D)  are of embryonic origin and function in embryo nutrition. 
E)  are of maternal origin and function in embryo gas exchange.

Question 11

Thalidomide, now banned for use as a sedative in 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 arm and leg deformities, suggesting that the drug most likely influenced

Accepted Answer

A)  early cleavage divisions. 
B)  determination of the polarity of the zygote. 
C)  differentiation of bone tissue. 
D)  morphogenesis. 
E)  organogenesis. 
A)  early cleavage divisions. 
B)  determination of the polarity of the zygote. 
C)  differentiation of bone tissue. 
D)  morphogenesis. 
E)  organogenesis.

Question 12

In placental mammals, the yolk sac

Accepted Answer

A)  transfers nutrients from the yolk to the embryo. 
B)  differentiates into the placenta. 
C)  becomes a fluid-filled sac that surrounds and protects the embryo. 
D)  produces blood cells that then migrate into the embryo. 
E)  stores waste products from the embryo until the placenta develops. 
A)  transfers nutrients from the yolk to the embryo. 
B)  differentiates into the placenta. 
C)  becomes a fluid-filled sac that surrounds and protects the embryo. 
D)  produces blood cells that then migrate into the embryo. 
E)  stores waste products from the embryo until the placenta develops.

Question 13

In an egg cell 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. 
E)  the zygote would not contain maternal and paternal chromosomes. 
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. 
E)  the zygote would not contain maternal and paternal chromosomes.

Question 14

Select the choice that correctly associates the organ with its embryonic sources.

Accepted Answer

A)  anterior pituitary gland-mesoderm and endoderm 
B)  thyroid gland-mesoderm and ectoderm 
C)  adrenal gland-ectoderm and mesoderm 
D)  skin-endoderm and mesoderm 
E)  brain-mesoderm and endoderm 
A)  anterior pituitary gland-mesoderm and endoderm 
B)  thyroid gland-mesoderm and ectoderm 
C)  adrenal gland-ectoderm and mesoderm 
D)  skin-endoderm and mesoderm 
E)  brain-mesoderm and endoderm

Question 15

In frog embryos, the blastopore becomes the

Accepted Answer

A)  anus. 
B)  ears. 
C)  eyes. 
D)  nose. 
E)  mouth. 
A)  anus. 
B)  ears. 
C)  eyes. 
D)  nose. 
E)  mouth.

Question 16

Changes in both cell shape and cell position occur extensively during

Accepted Answer

A)  gastrulation, but not organogenesis or cleavage. 
B)  organogenesis, but not gastrulation or cleavage. 
C)  cleavage, but not gastrulation or organogenesis. 
D)  gastrulation and organogenesis, but not cleavage. 
E)  gastrulation, organogenesis, and cleavage. 
A)  gastrulation, but not organogenesis or cleavage. 
B)  organogenesis, but not gastrulation or cleavage. 
C)  cleavage, but not gastrulation or organogenesis. 
D)  gastrulation and organogenesis, but not cleavage. 
E)  gastrulation, organogenesis, and cleavage.

Question 17

Hans Spemann and colleagues developed the concept of the primary organizer in amphibian embryos while studying the

Accepted Answer

A)  medial cells between the optic cups. 
B)  anterior terminus of the notochord. 
C)  lateral margins of the neural tube. 
D)  posterior edge of the dorsal ectoderm. 
E)  dorsal lip of the blastopore. 
A)  medial cells between the optic cups. 
B)  anterior terminus of the notochord. 
C)  lateral margins of the neural tube. 
D)  posterior edge of the dorsal ectoderm. 
E)  dorsal lip of the blastopore.

Question 18

In a frog embryo, gastrulation

Accepted Answer

A)  produces a blastocoel displaced into the animal hemisphere. 
B)  occurs along the primitive streak in the animal hemisphere. 
C)  is impossible because of the large amount of yolk in the ovum. 
D)  proceeds by involution as cells roll over the lip of the blastopore. 
E)  occurs within the inner cell mass that is embedded in the large amount of yolk. 
A)  produces a blastocoel displaced into the animal hemisphere. 
B)  occurs along the primitive streak in the animal hemisphere. 
C)  is impossible because of the large amount of yolk in the ovum. 
D)  proceeds by involution as cells roll over the lip of the blastopore. 
E)  occurs within the inner cell mass that is embedded in the large amount of yolk.

Question 19

In humans, identical twins are possible because

Accepted Answer

A)  cytoplasmic determinants are distributed unevenly in unfertilized eggs. 
B)  extraembryonic cells interact with the zygote nucleus. 
C)  convergent extension occurs. 
D)  early blastomeres can form a complete embryo if isolated. 
E)  the gray crescent divides the dorsal-ventral axis into new cells. 
A)  cytoplasmic determinants are distributed unevenly in unfertilized eggs. 
B)  extraembryonic cells interact with the zygote nucleus. 
C)  convergent extension occurs. 
D)  early blastomeres can form a complete embryo if isolated. 
E)  the gray crescent divides the dorsal-ventral axis into new cells.

Question 20

In mammals, the nuclei resulting from the union of the sperm and the egg are first truly diploid at the end of the

Accepted Answer

A)  acrosomal reaction. 
B)  completion of spermatogenesis. 
C)  initial cleavage. 
D)  activation of the egg. 
E)  completion of gastrulation. 
A)  acrosomal reaction. 
B)  completion of spermatogenesis. 
C)  initial cleavage. 
D)  activation of the egg. 
E)  completion of gastrulation.

Exam 47: Animal Development

An embryo with meroblastic cleavage, extraembryonic membranes, and a primitive streak must be that of

The pattern of embryonic development in which only the cells lacking yolk subsequently undergo cleavage is called

An open space within the gastrula is the

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

Which of the following is a correct description of an anatomical relationship?

Fertilization of an egg without activation is most like

Cells move to new positions as an embryo establishes its three germ tissue layers during

During fertilization, the acrosomal contents

Human trophoblasts

Thalidomide, now banned for use as a sedative in 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 arm and leg deformities, suggesting that the drug most likely influenced

In placental mammals, the yolk sac

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

Select the choice that correctly associates the organ with its embryonic sources.

In frog embryos, the blastopore becomes the

Changes in both cell shape and cell position occur extensively during

Hans Spemann and colleagues developed the concept of the primary organizer in amphibian embryos while studying the

In a frog embryo, gastrulation

In humans, identical twins are possible because

In mammals, the nuclei resulting from the union of the sperm and the egg are first truly diploid at the end of the

Introduction: Themes in the Study of Life

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

From Gene to Protein

Regulation of Gene Expression

Viruses

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

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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