Question 1

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

Accepted Answer

A) inner cell mass. 
B) endoderm. 
C) chorion. 
D) mesoderm. 
E) trophoblast. 
A) inner cell mass. 
B) endoderm. 
C) chorion. 
D) mesoderm. 
E) trophoblast. E

Question 2

Even in the absence of sperm, metabolic activity in an egg can be artificially activated by

Accepted Answer

A) abnormally high levels of carbonic acid in the cytosol. 
B) abnormally low levels of extracellular oxygen. 
C) injection of calcium ions into the cytosol. 
D) exposure to the low pH of the uterus. 
E) depletion of its ATP supplies. 
A) abnormally high levels of carbonic acid in the cytosol. 
B) abnormally low levels of extracellular oxygen. 
C) injection of calcium ions into the cytosol. 
D) exposure to the low pH of the uterus. 
E) depletion of its ATP supplies. C

Question 3

The cortical reaction occurs in which animals?

Accepted Answer

A) birds and reptiles 
B) sea urchins, mammals, and fishes 
C) amphibians, birds, and invertebrates 
D) mammals and invertebrates 
E) birds and fishes 
A) birds and reptiles 
B) sea urchins, mammals, and fishes 
C) amphibians, birds, and invertebrates 
D) mammals and invertebrates 
E) birds and fishes B

Question 4

The formation of the fertilization membrane requires an increase in the availability of

Accepted Answer

A) bicarbonate ions. 
B) calcium ions. 
C) hydrogen ions. 
D) potassium ions. 
E) sodium ions. 
A) bicarbonate ions. 
B) calcium ions. 
C) hydrogen ions. 
D) potassium ions. 
E) sodium ions.

Question 5

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.

Question 6

At the moment of sperm penetration, human eggs

Accepted Answer

A) have used flagellar propulsion to move from the ovary to the oviduct. 
B) accept as many sperm as possible in order to select the one with the highest fertility. 
C) are still located within the ovary. 
D) have a paper-thin cell of calcium carbonate that prevents desiccation. 
E) are still surrounded by follicular cells. 
A) have used flagellar propulsion to move from the ovary to the oviduct. 
B) accept as many sperm as possible in order to select the one with the highest fertility. 
C) are still located within the ovary. 
D) have a paper-thin cell of calcium carbonate that prevents desiccation. 
E) are still surrounded by follicular cells.

Question 7

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 8

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. 
E) increases as the number of the blastomeres stays the same. 
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. 
E) increases as the number of the blastomeres stays the same.

Question 9

Pregnant women are often advised to supplement their diet with folic acid to prevent neural tube defects such as those characteristic of

Accepted Answer

A) vestigial tails. 
B) spina bifida. 
C) herniated vertebral disks. 
D) spinal stenosis. 
E) spinal muscular atrophy. 
A) vestigial tails. 
B) spina bifida. 
C) herniated vertebral disks. 
D) spinal stenosis. 
E) spinal muscular atrophy.

Question 10

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 11

Cells transplanted from the neural tube of a frog embryo to the ventral part of another embryo develop into nervous system tissues. This result indicates that the transplanted cells were

Accepted Answer

A) totipotent. 
B) determined. 
C) differentiated. 
D) mesenchymal. 
E) apoptotic. 
A) totipotent. 
B) determined. 
C) differentiated. 
D) mesenchymal. 
E) apoptotic.

Question 12

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 grey 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 grey crescent divides the dorsal-ventral axis into new cells.

Question 13

If gastrulation were blocked by an environmental toxin, then

Accepted Answer

A) cleavage would not occur in the zygote. 
B) embryonic germ layers would not form. 
C) fertilization would be blocked. 
D) the blastula would not be formed. 
E) the blastopore would form above the grey crescent in the animal pole. 
A) cleavage would not occur in the zygote. 
B) embryonic germ layers would not form. 
C) fertilization would be blocked. 
D) the blastula would not be formed. 
E) the blastopore would form above the grey crescent in the animal pole.

Question 14

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

Accepted Answer

A) bird. 
B) fish. 
C) frog. 
D) eutherian (placental)mammal. 
E) reptile. 
A) bird. 
B) fish. 
C) frog. 
D) eutherian (placental)mammal. 
E) reptile.

Question 15

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

Question 16

Which of these animals is a diploblast?

Accepted Answer

A) jellyfish 
B) sea urchin 
C) frog 
D) chick 
E) fruit fly 
A) jellyfish 
B) sea urchin 
C) frog 
D) chick 
E) fruit fly

Question 17

Fertilization normally

Accepted Answer

A) reinstates diploidy. 
B) follows gastrulation. 
C) is required for parthenogenesis. 
D) merges two diploid cells into one haploid cell. 
E) precedes ovulation. 
A) reinstates diploidy. 
B) follows gastrulation. 
C) is required for parthenogenesis. 
D) merges two diploid cells into one haploid cell. 
E) precedes ovulation.

Question 18

What structural adaptation in chickens allows them to lay their eggs in arid environments rather than in water?

Accepted Answer

A) extraembryonic membranes 
B) yolk 
C) cleavage 
D) gastrulation 
E) development of the brain from ectoderm 
A) extraembryonic membranes 
B) yolk 
C) cleavage 
D) gastrulation 
E) development of the brain from ectoderm

Question 19

The migratory neural crest cells

Accepted Answer

A) form most of the central nervous system. 
B) serve as precursor cells for the notochord. 
C) form the spinal cord in the frog. 
D) form neural and non-neural structures in the periphery. 
E) form the lining of the lungs and of the digestive tract. 
A) form most of the central nervous system. 
B) serve as precursor cells for the notochord. 
C) form the spinal cord in the frog. 
D) form neural and non-neural structures in the periphery. 
E) form the lining of the lungs and of the digestive tract.

Question 20

Symptoms of Kartagener's syndrome include frequent sinus and bronchial infections, reversal of chest and abdominal organs, and afflicted males produce immotile sperm. This syndrome is a result of

Accepted Answer

A) deformation of the ZPA. 
B) immotile cilia. 
C) immotile flagella. 
D) motile flagella. 
E) motile cilia. 
A) deformation of the ZPA. 
B) immotile cilia. 
C) immotile flagella. 
D) motile flagella. 
E) motile cilia.

Exam 47: Animal Development

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

Even in the absence of sperm, metabolic activity in an egg can be artificially activated by

The cortical reaction occurs in which animals?

The formation of the fertilization membrane requires an increase in the availability of

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

At the moment of sperm penetration, human eggs

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

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

Pregnant women are often advised to supplement their diet with folic acid to prevent neural tube defects such as those characteristic of

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

Cells transplanted from the neural tube of a frog embryo to the ventral part of another embryo develop into nervous system tissues. This result indicates that the transplanted cells were

In humans, identical twins are possible because

If gastrulation were blocked by an environmental toxin, then

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

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

Which of these animals is a diploblast?

Fertilization normally

What structural adaptation in chickens allows them to lay their eggs in arid environments rather than in water?

The migratory neural crest cells

Symptoms of Kartagener's syndrome include frequent sinus and bronchial infections, reversal of chest and abdominal organs, and afflicted males produce immotile sperm. This syndrome is a result of

Introduction: Evolution and Themes of Biology

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

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

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 Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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