Deck 51: Animal Reproduction

Question 1

The roles of testosterone in male reproductive function include all of the following EXCEPT

A) stimulating spermatogenesis by the Leydig cells.
B) stimulating spermatogenesis by the Sertoli cells.
C) stimulating growth of the reproductive tract.
D) inhibiting LH secretion.
E) stimulating growth of facial hair.

Answer 1

stimulating spermatogenesis by the Leydig cells.

Question 2

Maintenance of the uterine lining during pregnancy in mammals requires

A) estradiol.
B) testosterone.
C) cortisol.
D) aldosterone.
E) progesterone.

Answer 2

progesterone.

Question 3

Which of the following organisms would most likely produce asexually?

A) a fish in a tidal zone
B) a haploid lizard
C) a mammal
D) a queen honeybee
E) None of these organisms could produce asexually.

Answer 3

a haploid lizard

Question 4

The fact that regeneration is a common type of reproduction in invertebrates suggests that

A) fertilization of eggs is not necessary.
B) sexual reproduction is too costly.
C) mitosis must occur before differentiation can begin.
D) all the adult cells of many invertebrates retain the molecular machinery necessary to form a complete animal.
E) invertebrates live in highly unstable environments.

Question 5

An animal that can fertilize its own eggs is

A) a synchronous hermaphrodite.
B) a sequential hermaphrodite.
C) producing asexually.
D) a protrandous hermaphrodite.
E) a protogynous hermaphrodite.

Question 6

Which of the following is not true for both male and female gametogenesis?

A) Gametes develop in the gonads.
B) Germ cells multiply by mitosis.
C) Primary cells (spermatocytes and oocytes) are diploid.
D) Gametes are formed by meiosis.
E) One primary cell produces one mature gamete.

Question 7

Place the following events of fertilization in the correct chronological order.
(1) Sperm contacts the cumulus mass.
(2) Proteolytic enzymes are released from the acrosome.
(3) Sperm contacts the plasma membrane of the ovum.
(4) Sperm passes through the zona pellucida.
(5) Sperm increase ATP production.

A) 5,1,2,4,3
B) 1,5,4,3,2
C) 1,2,4,3,5
D) 5,2,4,3,1
E) 3,5,2,1,4

Question 8

What would result if more than one sperm fertilized an egg?

A) hermaphroditism
B) parthenogenesis
C) polyploidy
D) twins
E) haploidy

Question 9

Which of the following comparisons of oviparity and viviparity is incorrect?

A) In viviparity, the mother has a lower metabolic investment in her young than in oviparity.
B) Viviparity occurs in most mammals; oviparity occurs in birds.
C) In viviparity, fertilized eggs are retained within the mother; in oviparity, the fertilized eggs are released into the environment.
D) In viviparity, there is parental care; there is no parental care in oviparity.
E) In viviparity, the fertilized egg does not need protection from dessication; in oviparity the fertilized egg often needs protection from dessication.

Question 10

How does the embryo of an oviparous animal obtain nutrients to grow?

A) from the mother's body
B) from the yolk
C) through tiny pores in the shell of the egg
D) from the nucleus within the yolk
E) from the egg cytoplasm

Question 11

Why are the male gonads held outside the body cavity?

A) Normal body temperature is too high for spermatogenesis.
B) Normal body pH is too low for spermatogenesis.
C) Gonadotropins are inactivated at normal body temperature.
D) Sperm development proceeds much slower at normal body temperature.
E) Leydig cells will die at normal body temperature.

Question 12

Male secondary sex characteristics include all of the following EXCEPT

A) facial hair.
B) peacock feathers.
C) testes.
D) deepening voice.
E) increased muscle size.

Question 13

When testosterone levels in a male are high

A) GnRH production is inhibited.
B) FSH release is stimulated.
C) LH release is inhibited.
D) GnRH release is stimulated.
E) both GnRH production and LH release are inhibited.

Question 14

In female mammals, oogenesis

A) occurs in the uterus.
B) requires the production of primary oocytes at puberty.
C) is cyclical.
D) requires progesterone.
E) is a continuous process throughout adulthood.

Question 15

During the follicular phase of the ovarian cycle,

A) meiosis I is completed to form the secondary oocyte.
B) progesterone is secreted from the corpus luteum.
C) estradiol is secreted from the cumulus mass.
D) both meiosis I and progesterone secretion from the corpus luteum occur.
E) both meiosis I and estradiol secretion from the cumulus mass occur.

Question 16

Which of the following statements concerning the corpus luteum is INCORRECT?

A) Secretions of the corpus luteum inhibit LH and FSH secretion.
B) Secretions of the corpus luteum prepare the uterus for implantation of the embryo.
C) Secretions of the corpus luteum prevent the maturation of primary oocytes.
D) The major hormone secreted from the corpus luteum is progesterone.
E) The major hormone secreted from the corpus luteum is estradiol.

Question 17

If pregnancy does not occur, then

A) chorionic gonadotropin levels increase.
B) progesterone levels decrease and estrogen levels increase.
C) both progesterone and estradiol levels increase.
D) LH and FSH levels decrease.
E) both progesterone and estradiol levels decrease.

Question 18

Which of the following animals would have a placenta?

A) the marsupial mammal, opossum
B) the platypus
C) the rat
D) the bullfrog
E) a fish

Question 19

Which of the following events occurs during the first trimester of pregnancy?

A) The heart begins to form.
B) The lungs fully mature.
C) The fetus grows to 1 foot in length.
D) The fetus has a very rapid phase of growth.
E) All of these events occur during the first trimester.

Question 20

In lactation, milk production is stimulated by _____, while milk release is stimulated by _________.

A) oxytocin, prolactin
B) progesterone, oxytocin
C) prolactin, oxytocin
D) prostaglandin, oxytocin
E) progesterone, prolactin

Question 21

The act of nursing stimulates the contraction of smooth muscle cells in the breast. If a newborn infant is unable to nurse, then

A) progesterone secretion is not inhibited.
B) milk is not produced.
C) oxytocin is not secreted.
D) prolactin is not secreted.
E) prostaglandins are not secreted.

Question 22

Which of the following environmental factors might lead to year-round, rather than seasonal, reproductive activity?

A) a yearly rainy season
B) stable food supplies
C) day length
D) daily ocean tides
E) seasonal temperature changes

Question 23

Erectile dysfunction can be treated by drugs that increase levels of nitric oxide.

Question 24

FSH stimulates the activity of Leydig cells and LH stimulates the activity of Sertoli cells.

Question 25

A human female has the largest number of primary oocytes at the onset of puberty.

Question 26

FSH secreted by the pituitary stimulates fluid secretion into the antrum of the follicle.

Question 27

Menstruation is initiated when progesterone levels increase.

Question 28

The length of a pregnancy is influenced by the size of both the mother and the embryo.

Question 29

There is no possibility of a male contraceptive ever being developed for humans.