Question 1

The snakes include some rather short and some incredibly long species, with a variation from about 100 to over 300 vertebrae.What developmental mechanism is the best candidate for changing the number of vertebrae in evolution?

Accepted Answer

A)  Changes in genes that lay down extracellular matrix in bone
B)  Changes in genes necessary for neural crest development
C)  Changes in genes that control mitosis
D)  Changes in the somitogenesis clockE) A) and D)
F) A) and C)

Question 2

Working in an experimental fertility clinic, a researcher removes one cell from an 8-cell stage chimpanzee embryo.What is the likely result?

Accepted Answer

A)  Both the cell and the blastula will die.
B)  All the cells are already committed and therefore are not viable.
C)  The embryo from which the cell was removed still remains viable and can form a normal chimp.D) B) and C)
E) A) and C)

Question 3

In human females, what process causes milk production?

Accepted Answer

A)  Stimulation of the alveoli of the mammary glands by prolactin from the anterior pituitary gland.
B)  Stimulation of the alveoli of the mammary glands by oxytocin from the anterior pituitary gland.
C)  Stimulation of the alveoli of the mammary glands by prolactin from the posterior pituitary gland.
D)  Stimulation of the alveoli of the mammary glands by oxytocin from the posterior pituitary gland.E) All of the above
F) C) and D)

Question 4

Which of the following leads to the occurrence of vertebrate sense organs?

Accepted Answer

A)  both adrenal medullary cells and sympathetic neurons derive from the neural crest
B)  neural crest cells form both neurons that carry messages and cartilaginous bars
C)  the neural crest and associated sensory ganglia
D)  formation of the endodermE) A) and B)
F) B) and D)

Question 5

What pattern of cleavage is characteristic of mammals?

Accepted Answer

A)  holoblastic cleavage with eggs containing little or no yolk
B)  some yolk, and cleavage resulting in vegetal and animal poles
C)  meroblastic cleavage with eggs containing almost entirely yolk
D)  holoblastic cleavage with eggs containing very little yolk, but with the inner cell mass concentrated at one poleE) B) and C)
F) A) and D)

Question 6

What would be the result of a mutation that reduces the amount of acrosomal enzymes?

Accepted Answer

A)  Male infertility due to inability of the sperm to tunnel through the blastula.
B)  Male infertility due to inability of the sperm to tunnel through the zona pellucida.
C)  Female infertility due to blockage of sperm from tunneling through the allantois.
D)  Female infertility due to blockage of sperm from tunneling through the archenteron.E) A) and C)
F) All of the above

Question 7

When the placenta is delivered, what event allows secretion of prolactin and milk production?

Accepted Answer

A)  a surge of adrenaline and endorphins
B)  sudden drop in progesterone and estradiol
C)  gradual drop in oxytocin
D)  sudden rise in FSH and LHE) A) and B)
F) All of the above

Question 8

What human organ is formed from two genetically-different tissues?

Accepted Answer

A)  neural crest
B)  neural tube
C)  placenta
D)  uterusE) C) and D)
F) A) and C)

Question 9

How is brain growth in humans different from other mammals?

Accepted Answer

A)  In humans brain growth is complete by the third trimester.
B)  In humans brain growth stops at birth.
C)  Human growth is not allometric.
D)  In humans brain growth continues after birth.E) All of the above
F) C) and D)

Question 10

What structure is formed from both fetal and maternal tissue?

Accepted Answer

A)  chorion
B)  placenta
C)  yolk sac
D)  amnionE) B) and C)
F) A) and D)

Question 11

What prevents menstruation from occurring in the 10th week when the corpus luteum regresses?

Accepted Answer

A)  The follicle takes over secretion of hCG.
B)  The follicle takes over secretion of estradiol and progesterone.
C)  The placenta takes over secretion of estradiol and progesterone.
D)  The cervix takes over secretion of oxytocin and prostaglandins.E) A) and B)
F) B) and D)

Question 12

Which of the following activates the egg?

Accepted Answer

A)  entrance of sperm into the zona pellucida
B)  contact of sperm with the outside of the zona pellucida
C)  contact of sperm with the vitelline envelope
D)  fusion of sperm and egg membranesE) C) and D)
F) A) and C)

Question 13

In blind cave fish, eyes do not form.However, transplantation of the lens from a closely-related aboveground fish into the optic cup of the cave fish induces eye development.What does this suggest about the loss of vision in the cave fish?

Accepted Answer

A)  Primary induction of the eye fails in the cave fish because the lens lacks some critical signal.
B)  Secondary induction of the eye fails in the cave fish because the lens lacks some critical signal.
C)  Primary induction of the eye fails in the cave fish because the optic cup lacks the ability to receive some critical signal.
D)  Secondary induction of the eye fails in the cave fish because the optic cup lacks the ability to receive some critical signal.E) C) and D)
F) A) and C)

Question 14

What would result if too many cells left the surface of the embryo to move inside during gastruation?

Accepted Answer

A)  Too little endoderm, resulting in missing gut and organs
B)  Too little ectoderm, resulting in missing nervous system or skin
C)  Problems in muscle development
D)  Too little protoderm, resulting in missing organsE) A) and B)
F) C) and D)

Question 15

What are the two components of the human placenta?

Accepted Answer

A)  chorionic frondosum and chorionic villus
B)  chorionic frondosum and decidua basalis
C)  decidua basalis and chorionic villus
D)  chorionic villus and endometriumE) B) and C)
F) C) and D)

Question 16

In this diagram, which of the following numbers represents the actual event of egg activation?

Accepted Answer

A)  I
B)  II
C)  III
D)  IVE) A) and B)
F) A) and C)

Question 17

What would result if an error inside gastrulation caused too few cells inside the archenteron?

Accepted Answer

A)  Too little endoderm, resulting in missing gut and organs
B)  Too little ectoderm, resulting in missing nervous system or skin
C)  Problems in muscle development
D)  Too little protoderm, resulting in missing organsE) B) and C)
F) C) and D)

Question 18

400 micrograms a day of folic acid are recommended for all women of child-bearing age.Folic acid helps prevent neural tube defects in the first weeks of pregnancy, before most women even realize they are pregnant (and almost half of pregnancies in the U.S.are unintended) .Knowing that folic acid promotes proper neural tube closure, which disease can be prevented by this supplement?

Accepted Answer

A)  Spina bifida -- the vertebrae are unfused and may allow the spinal cord to protrude outside the body
B)  Horseshoe kidney -- the two kidneys are fused together across the midline
C)  Esophageal atresia -- the esophagous ends in a pouch, unconnected to the stomach
D)  Chronic otitis media -- frequent ear infections that can result from blocked eustachian tubesE) A) and D)
F) B) and C)

Question 19

What would result if a defect in gastrulation caused too little mesoderm inside the embryo?

Accepted Answer

A)  Too little endoderm, resulting in missing gut and organs
B)  Too little ectoderm, resulting in missing nervous system or skin
C)  Problems in muscle development
D)  Too little protoderm, resulting in missing organsE) None of the above
F) A) and C)

Question 20

You are studying the development of a poorly-understood species at the 8-cell stage.You use a laser to zap away a certain one of the eight cells, and discover that part of the gut is missing once the embryos finish development.Your colleague, who is working on a different species, uses the laser to blast away one of the cells in her embryos, zapping each of the possible cells in a set of eight experiments.However, when the embryos finish development, every one is perfectly normal! What can you conclude about the two species?

Accepted Answer

A)  The first species has regulative development, the second has non-regulative development.
B)  The first species has non-regulative development, the second has regulative development.
C)  Both species have regulative development.
D)  Both species have non-regulative development.E) B) and D)
F) All of the above

Exam 53: Animal Development

What structure is formed from both fetal and maternal tissue?

Correct Answer
verified

How is brain growth in humans different from other mammals?

Correct Answer
verified

In this diagram, which of the following numbers represents the actual event of egg activation?

Correct Answer
verified

In blind cave fish, eyes do not form.However, transplantation of the lens from a closely-related aboveground fish into the optic cup of the cave fish induces eye development.What does this suggest about the loss of vision in the cave fish?

Correct Answer
verified

What pattern of cleavage is characteristic of mammals?

Correct Answer
verified

Which of the following activates the egg?

Correct Answer
verified

What would result if an error inside gastrulation caused too few cells inside the archenteron?

Correct Answer
verified

When the placenta is delivered, what event allows secretion of prolactin and milk production?

Correct Answer
verified

In human females, what process causes milk production?

Correct Answer
verified

What are the two components of the human placenta?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

What would result if too many cells left the surface of the embryo to move inside during gastruation?

Correct Answer
verified

What would result if a defect in gastrulation caused too little mesoderm inside the embryo?

Correct Answer
verified

What would be the result of a mutation that reduces the amount of acrosomal enzymes?

Correct Answer
verified

What prevents menstruation from occurring in the 10^th week when the corpus luteum regresses?

Correct Answer
verified

Working in an experimental fertility clinic, a researcher removes one cell from an 8-cell stage chimpanzee embryo.What is the likely result?

Correct Answer
verified

The snakes include some rather short and some incredibly long species, with a variation from about 100 to over 300 vertebrae.What developmental mechanism is the best candidate for changing the number of vertebrae in evolution?

Correct Answer
verified

What human organ is formed from two genetically-different tissues?

Correct Answer
verified

Which of the following leads to the occurrence of vertebrate sense organs?

Correct Answer
verified

Exam 53: Animal Development

What structure is formed from both fetal and maternal tissue?

Correct AnswerverifiedShow Answer

How is brain growth in humans different from other mammals?

Correct AnswerverifiedShow Answer

In this diagram, which of the following numbers represents the actual event of egg activation?

Correct AnswerverifiedShow Answer

In blind cave fish, eyes do not form.However, transplantation of the lens from a closely-related aboveground fish into the optic cup of the cave fish induces eye development.What does this suggest about the loss of vision in the cave fish?

Correct AnswerverifiedShow Answer

What pattern of cleavage is characteristic of mammals?

Correct AnswerverifiedShow Answer

Which of the following activates the egg?

Correct AnswerverifiedShow Answer

What would result if an error inside gastrulation caused too few cells inside the archenteron?

Correct AnswerverifiedShow Answer

When the placenta is delivered, what event allows secretion of prolactin and milk production?

Correct AnswerverifiedShow Answer

In human females, what process causes milk production?

Correct AnswerverifiedShow Answer

What are the two components of the human placenta?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

What would result if too many cells left the surface of the embryo to move inside during gastruation?

Correct AnswerverifiedShow Answer

What would result if a defect in gastrulation caused too little mesoderm inside the embryo?

Correct AnswerverifiedShow Answer

What would be the result of a mutation that reduces the amount of acrosomal enzymes?

Correct AnswerverifiedShow Answer

What prevents menstruation from occurring in the 10th week when the corpus luteum regresses?

Correct AnswerverifiedShow Answer

Working in an experimental fertility clinic, a researcher removes one cell from an 8-cell stage chimpanzee embryo.What is the likely result?

Correct AnswerverifiedShow Answer

The snakes include some rather short and some incredibly long species, with a variation from about 100 to over 300 vertebrae.What developmental mechanism is the best candidate for changing the number of vertebrae in evolution?

Correct AnswerverifiedShow Answer

What human organ is formed from two genetically-different tissues?

Correct AnswerverifiedShow Answer

Which of the following leads to the occurrence of vertebrate sense organs?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

What prevents menstruation from occurring in the 10^th week when the corpus luteum regresses?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified