BIO 117 Exam 3 Study Guide
What is meant by the term somite? - ANSWER:A block of mesodermal tissue that gives rise to muscles,
bone, and skin.
Which of the following statements regarding animal development are incorrect? - ANSWER:-Animals
have two germ layers
-The neural tube forms after organogensis is complete
Fungi spend most of their lives feeding. Considering a typical mushroom, which is the longest-lived
component of this life cycle? - ANSWER:The haploid mycelium.
The basic bilaterian body form plan can be thought of as simply _____. - ANSWER:a tube within a tube.
Why was the evolution of a coelom a critically important innovation for animals? - ANSWER:It enables
the internal organs to move independently of the outer tubes, or exterior of the animal.
Which of the following is an example of homology (similarity due to common ancestry)? -
ANSWER:cnidocytes (stinging cells) in jellyfish and sea anemones.
In a tube-within-a-tube body plan, what is the interior tube derived from? - ANSWER:endoderm.
What synapomorphy (shared, derived trait) distinguishes animals as a monophyletic group, distinct from
choanoflagellates? - ANSWER:multicellularity.
The fundamental reproductive cell produced by fungi is the _______. - ANSWER:spore
During gastrulation in frogs, a rod of mesoderm under the dorsal surface forms the _____. -
ANSWER:notochord
During gastrulation in frogs, cells from the animal pole spread over the embryo and form the _____. -
ANSWER:ectoderm
The notochord functions as a core around which mesodermal cells form the frog's _____. -
ANSWER:backbone
An ectodermal thickening above the frog's notochord forms a _____. - ANSWER:neural plate
The _____ is(are) formed when the neural folds join and a portion of the neural plate sinks beneath the
embryo's surface. - ANSWER:neural tube
The enlarged anterior portion of the neural tube will develop into a frog's _____. - ANSWER:brain
The posterior portion of the neural tube will develop into the frog's _____. - ANSWER:spinal cord
Differentiating between cleavage, gastrulation, and organogenesisDetermine which terms, phrases, and
images describe each phase of development.Drag each item to the appropriate bin. - ANSWER:Cleavage:
blastula, cytoplasm partitioned into many cells, (yellow ball of cells)
, Gastrulation: embryonic germ layers form, gastrula, blastopore, (ball of cells with three layers yellow, red
and blue)
organogenesis: organs begin to develop from germ layers, neural tube, somites
Organogenesis in a frog embryoTissue and organ formation begins during the process of organogenesis.
Which five of the following statements are true about organogenesis in a frog embryo? - ANSWER:-The
endoderm gives rise to the lining of the frog's digestive tract.
-The neural tube forms from ectoderm and develops into the central nervous system.
-The notochord does not persist in adult frogs.
-Somites form along the length of the notochord and neural tube.
-Some somite cells migrate to other locations in the developing embryo.
Which of the following statements regarding animal development is not accurate? - ANSWER:The neural
tube forms after organogenesis is complete.
What is the cortical reaction? - ANSWER:the formation of a fertilization envelope that bars additional
sperm from entry into the egg.
As cleavage continues, a zygote forms into a solid multicellular ball called a(n) _____. - ANSWER:morula
Several hours after fertilization, cleavage results in the formation of a hollow ball of cells called a _____. -
ANSWER:blastula
The three-layered embryo is the _____. - ANSWER:gastrula
The _____ eventually develops into the sea urchin's digestive tract. - ANSWER:archenteron
During gastrulation, invagination occurs at the _____. - ANSWER:blastopore
In vertebrates, the ectoderm gives rise to the _____. - ANSWER:outer layer of skin
In animal development, which of the following best describes the process of cleavage? -
ANSWER:Mitosis
What are the cells created by cleavage called? - ANSWER:Blastomeres
Which of the following are the three germ layers contained in the gastrula? - ANSWER:Ectoderm,
mesoderm, endoderm
Which of the following stages of development is defined by the three embryonic tissue layers (ectoderm,
mesoderm, and endoderm)? - ANSWER:gastrula
What happens to a cell during the process of differentiation? - ANSWER:It undergoes a change toward a
more specialized form or function.
A child is born without a fully developed pancreas. He is normal in all other respects, and thus doctors
believe that the problem most likely began early in development. During which of the following
processes did the original error most likely occur? - ANSWER:Endoderm formation
What is meant by the term somite? - ANSWER:A block of mesodermal tissue that gives rise to muscles,
bone, and skin.
Which of the following statements regarding animal development are incorrect? - ANSWER:-Animals
have two germ layers
-The neural tube forms after organogensis is complete
Fungi spend most of their lives feeding. Considering a typical mushroom, which is the longest-lived
component of this life cycle? - ANSWER:The haploid mycelium.
The basic bilaterian body form plan can be thought of as simply _____. - ANSWER:a tube within a tube.
Why was the evolution of a coelom a critically important innovation for animals? - ANSWER:It enables
the internal organs to move independently of the outer tubes, or exterior of the animal.
Which of the following is an example of homology (similarity due to common ancestry)? -
ANSWER:cnidocytes (stinging cells) in jellyfish and sea anemones.
In a tube-within-a-tube body plan, what is the interior tube derived from? - ANSWER:endoderm.
What synapomorphy (shared, derived trait) distinguishes animals as a monophyletic group, distinct from
choanoflagellates? - ANSWER:multicellularity.
The fundamental reproductive cell produced by fungi is the _______. - ANSWER:spore
During gastrulation in frogs, a rod of mesoderm under the dorsal surface forms the _____. -
ANSWER:notochord
During gastrulation in frogs, cells from the animal pole spread over the embryo and form the _____. -
ANSWER:ectoderm
The notochord functions as a core around which mesodermal cells form the frog's _____. -
ANSWER:backbone
An ectodermal thickening above the frog's notochord forms a _____. - ANSWER:neural plate
The _____ is(are) formed when the neural folds join and a portion of the neural plate sinks beneath the
embryo's surface. - ANSWER:neural tube
The enlarged anterior portion of the neural tube will develop into a frog's _____. - ANSWER:brain
The posterior portion of the neural tube will develop into the frog's _____. - ANSWER:spinal cord
Differentiating between cleavage, gastrulation, and organogenesisDetermine which terms, phrases, and
images describe each phase of development.Drag each item to the appropriate bin. - ANSWER:Cleavage:
blastula, cytoplasm partitioned into many cells, (yellow ball of cells)
, Gastrulation: embryonic germ layers form, gastrula, blastopore, (ball of cells with three layers yellow, red
and blue)
organogenesis: organs begin to develop from germ layers, neural tube, somites
Organogenesis in a frog embryoTissue and organ formation begins during the process of organogenesis.
Which five of the following statements are true about organogenesis in a frog embryo? - ANSWER:-The
endoderm gives rise to the lining of the frog's digestive tract.
-The neural tube forms from ectoderm and develops into the central nervous system.
-The notochord does not persist in adult frogs.
-Somites form along the length of the notochord and neural tube.
-Some somite cells migrate to other locations in the developing embryo.
Which of the following statements regarding animal development is not accurate? - ANSWER:The neural
tube forms after organogenesis is complete.
What is the cortical reaction? - ANSWER:the formation of a fertilization envelope that bars additional
sperm from entry into the egg.
As cleavage continues, a zygote forms into a solid multicellular ball called a(n) _____. - ANSWER:morula
Several hours after fertilization, cleavage results in the formation of a hollow ball of cells called a _____. -
ANSWER:blastula
The three-layered embryo is the _____. - ANSWER:gastrula
The _____ eventually develops into the sea urchin's digestive tract. - ANSWER:archenteron
During gastrulation, invagination occurs at the _____. - ANSWER:blastopore
In vertebrates, the ectoderm gives rise to the _____. - ANSWER:outer layer of skin
In animal development, which of the following best describes the process of cleavage? -
ANSWER:Mitosis
What are the cells created by cleavage called? - ANSWER:Blastomeres
Which of the following are the three germ layers contained in the gastrula? - ANSWER:Ectoderm,
mesoderm, endoderm
Which of the following stages of development is defined by the three embryonic tissue layers (ectoderm,
mesoderm, and endoderm)? - ANSWER:gastrula
What happens to a cell during the process of differentiation? - ANSWER:It undergoes a change toward a
more specialized form or function.
A child is born without a fully developed pancreas. He is normal in all other respects, and thus doctors
believe that the problem most likely began early in development. During which of the following
processes did the original error most likely occur? - ANSWER:Endoderm formation
