Question 1

When examining histological sections derived from the testes of male mammals, you come across cells that are near the lumen of the seminiferous tubules and connected by cytoplasmic bridges.Which cells have you found?

Accepted Answer

A)   Leydig cells
B)   Spermatogonia
C)   Secondary spermatocytes and/or spermatids
D)   Sertoli cells
E)   Mature sperm C

Question 2

Refer to the figure depicting the average blood concentrations of four circulating hormones in 100 healthy adult women.Each hormone plays a role in regulating some aspect of the ovarian and/or uterine cycle.  Based on the figure, which statement is true?

Accepted Answer

A)   The hormone represented by curve A is released by the anterior pituitary in response to GnRH.
B)   The hormone represented by curve B is secreted by the developing follicle.
C)   The hormone represented by curve C stimulates growth of the follicle.
D)   The hormone represented by curve D stimulates ovulation.
E)   The hormone represented by curve A is produced by the hypothalamus. A

Question 3

Blocks to polyspermy serve to

Accepted Answer

A)   fuse a haploid sperm with a haploid egg.
B)   prevent the union of an egg and sperm from different species.
C)   guarantee that only one sperm will enter the egg.
D)   metabolically activate the egg.
E)   guide sperm toward the egg. C

Question 4

Mammalian spermatocytes remain in cytoplasmic contact throughout their development

Accepted Answer

A)   to share nutrients.
B)   because primary spermatocytes lack two sex chromosomes.
C)   to share gene products of the X chromosomes following the first meiotic division.
D)   to prevent competition among the sperm prior to release.
E)   because spermatocytes are smaller than spermatids.

Question 5

Which cells would be found closest to the basement membrane of a seminiferous tubule?

Accepted Answer

A)   Spermatogonia
B)   Spermatids
C)   Primary spermatocytes
D)   Secondary spermatocytes
E)   Spermatozoa

Question 6

While examining histological sections derived from the ovaries of human females at various life stages, you come across a slide labeled "Section of an ovary from a mature female." You would expect to find all of these cells on the slide except for a(n)

Accepted Answer

A)   second polar body.
B)   arrested primary oocyte.
C)   secondary oocyte.
D)   first polar body.
E)   primary oocyte resuming meiosis.

Question 7

In humans, a primary oocyte is _______ and arrested in _______ of meiosis.

Accepted Answer

A)   haploid; prophase I
B)   diploid; prophase I
C)   haploid; prophase II
D)   diploid; prophase II
E)   haploid; metaphase

Question 8

A spontaneous abortion, commonly called a(n) _______, may result from a chromosomal abnormality in the embryo or from a problem in the process of implantation.

Accepted Answer

The answer of A spontaneous abortion, commonly called a(n) _______,...

Question 9

Which statement characterizes therians?

Accepted Answer

A)   They vary dramatically in developmental stage of offspring at birth.
B)   They do not have placentas.
C)   They are oviparous.
D)   They have external fertilization.
E)   Their young rely on yolk stored in the egg.

Question 10

Secondary sexual characteristics

Accepted Answer

A)   include the primary sex organs.
B)   are directly involved in reproduction.
C)   are responsible for differences in external appearance of the sexes.
D)   include the accessory sex organs.
E)   include the testes and ovaries.

Question 11

Mifepristone (formerly called RU-486) terminates a pregnancy by blocking the action of progesterone.The termination occurs because progesterone is needed to

Accepted Answer

A)   maintain the endometrium.
B)   trigger ovulation.
C)   prompt formation of the corpus luteum.
D)   promote ovarian development.
E)   initiate degeneration of the corpus luteum.

Question 12

If a man carries a genetic mutation that prevents the maintenance of cytoplasmic bridges between his secondary spermatocytes and his spermatids, would you expect that he would father only sons or only daughters? Explain your answer.

Accepted Answer

The answer of If a man carries a genetic mutation...

Question 13

A vasectomy is a relatively minor operation in which the _______ is/are cut and the loose ends are tied off.

Accepted Answer

A)   epididymis
B)   urethra
C)   oviduct
D)   vas deferens
E)   seminiferous tubules

Question 14

The uterus opens into the vagina at a muscular necklike region called the _______.

Accepted Answer

The answer of The uterus opens into the vagina at...

Question 15

During the evening hours you observe two salamanders in a pool, one is leading the other as if in a dance.It appears to be a mating ritual.At the conclusion of the ritual, you do not see any eggs in the water.Several days later you return and find a clutch of salamander eggs developing in the pool.What is a likely explanation for these observations?

Accepted Answer

A)   Because the organisms were in water, the eggs and sperm were most likely spawned into the water, but the eggs were initially not apparent because the jelly around them had not yet swelled with water.
B)   The gametes were spawned into the water column at a later date.
C)   The male and female salamander copulated, and the female retained the eggs internally allowing them to develop until they could survive on their own.
D)   The male and female salamander copulated, and the female retained the eggs internally until hatching. The clutch of eggs found were from a different species of salamander.
E)   The male laid a packet of sperm such as a spermatophore, which the female picked up in her reproductive tract. Fertilization was internal, and the eggs were laid following fertilization.

Question 16

Several days after her due date, a pregnant woman comes to the hospital in labor, but after a period of time, her labor contractions cease.Her physician administers Pitocin, a manufactured form of _______, which causes labor to resume.

Accepted Answer

The answer of Several days after her due date, a...

Question 17

Choose the correct pairing between cell type and ploidy.

Accepted Answer

A)   Primary spermatocyte: n
B)   Germ cell: n
C)   Secondary spermatocyte: n
D)   Spermatid: 2n
E)   Spermatogonium: n

Question 18

Which would be an expected outcome of removal of the prostate gland?

Accepted Answer

A)   Decrease in volume of semen by 60 percent
B)   Decrease in the pH of the male reproductive tract
C)   Failure of fibrinogen to convert semen into a gelatinous mass
D)   Greater survival of sperm once in the female reproductive tract
E)   Absence of secretions preceding climax

Question 19

Refer to the figure showing aphid reproductive cycles.  The organism labeled 1 is a female and is genetically identical to the organism(s) labeled _______.

Accepted Answer

The answer of Refer to the figure showing aphid reproductive...

Question 20

In oogenesis, the first meiotic division produces

Accepted Answer

A)   a secondary oocyte and the first polar body.
B)   a primary oocyte.
C)   an ootid and the second polar body.
D)   two secondary oocytes.
E)   an ovum and the second polar body.

Exam 42: Animal Reproduction