The Reproductive System, Chapter 27 P Besaw
Sperm is produced in the __________ of the testes.
seminiferous tubules
Sperm is stored in the __________.
epididymis
Why are the male testes located in the scrotum outside the body?
Immature sperm are temperature sensitive
A man who has had a successful orchiectomy may still be able to have children because ______.
the remaining testis is able, by itself, to produce a sufficient amount of testosterone
the seminiferous tubules of the remaining testis are still active
the epididymis posterior to the remaining testis is still functional
xxxx All of the listed responses are correct
Why does meiosis involve two nuclear divisions rather than one, as in mitosis?
Meiosis reduces the chromosome number by half.
At what point during meiosis do homologous chromosomes pair up?
prophase I
During meiosis, what does crossover promote?
Crossover promotes increased genetic variability among gametes.
Which of the following results from spermiogenesis?
sperm
Which of the following is the haploid cell produced as a result of meiosis I?
secondary spermatocyte
Which of the following cells is returned to the basal lamina to continue the pool of dividing germ cells?
type A daughter cell or spermatogonium
Which of the following inhibits the release of FSH from the anterior pituitary and GnRH from the hypothalamus when the sperm count is high?
inhibin
Which of the following keeps the concentration of testosterone in the vicinity of the spermatogenic cells high to stimulate spermatogenesis?
androgen-binding protein (ABP)
Which hormone promotes the formation of secondary sex characteristics such as the appearance of pubic, axillary, and facial hair, enhanced hair growth on the chest, and a deepening voice?
testosterone
The number of chromosomes in a human gamete is __________; this is referred to as the __________ chromosome number.
23; haploid
Genetic variation of individual chromosomes occurs during __________.
prophase I
Which of the following occurs during spermiogenesis?
sperm are produced
Enzymes that allow sperm to penetrate the egg are located in the __________ of the sperm cell.
acrosome
The release of __________ encourages interstitial endocrine cells to release __________.
luteinizing hormone; testosterone
What is the product of spermatogenesis?
formation of haploid spermatozoa
Which of the following organs is NOT a part of the HPG axis?
posterior pituitary gland
What is the function of the blood testis barrier?
to prevent activation of the immune system of the male against the developing sperm
Although effective in treating erectile dysfunction, Viagra has the side effect of reducing systemic blood pressure by causing ______.
relaxation of muscle tissue in arteries
What part of the female duct system is the usual site of fertilization of the ovulated oocyte?
uterine (fallopian) tube (oviduct)
Which structure of the female's external genitalia has erectile tissue like the penis?
clitoris
The __________, a layer of the endometrium, is shed during each menstruation and is then regenerated by the __________.
stratum functionalis; stratum basalis
The mammary glands are present in both sexes.
True
Which of the following is an INCORRECT matching of female reproductive structures with their functions?
xxxuterine tube/transport unfertilized ovum to uterus for removal from the body
vagina/birth canal
uterus/the womb (area of development of the fetus)
ovarian follicle/ovum (egg) production
Which layer of the uterus is the site for implantation of a fertilized egg?
stratum functionalis of the endometrium
Which of the following conditions might contribute to an increased probability of having an ectopic pregnancy?
decreased number of cilia in the uterine tubes
Which of the following cells is released during ovulation?
secondary oocyte
Why CAN'T polar bodies be fertilized?
Polar bodies lack nutrient-containing cytoplasm
How many functional gametes are produced by oogenesis?
one functional gamete
What event occurs during the proliferative phase?
ovulation
During what phase of the female's uterine (menstrual) cycle is the uterine lining shed?
menstrual phase
What hormone promotes ovulation?
luteinizing hormone (LH)
Formation of a secondary oocyte occurs during __________.
the follicular phase
A surge in __________ directly triggers ovulation.
luteinizing hormone (LH)
During the secretory phase of the uterine cycle __________.
the endometrium prepares for implantation
Which of the following is an effect of estrogen in females?
promotes oogenesis
Oocytes only complete meiosis II if they are fertilized.
True
Female infants are born with primary oocytes that are stalled in prophase I until puberty. At the onset of puberty, the ovaries begin oogenesis. During oogenesis, three polar bodies and one functional gamete are produced. Oogenesis is achieved through meiosis. However, the ovulated secondary oocyte arrests in metaphase II and does not complete meiosis II until it is fertilized
Dehydroepiandrosterone (DHEA) is the main androgen that is associated with female libido.
True
Why does only one egg, rather than four eggs, develop during oogenesis, given that spermatogenesis results in four sperm formed from one stem cell?
The unequal cytoplasmic division that results in one egg and three polar bodies ensures that a fertilized egg has ample nutrients for its journey to the uterus.
Amenorrhea can occur in women engaged in extremely strenuous physical activity, and also occurs in women who ______.
are pregnant
Which of the following is NOT a sexually transmitted bacterial disease?
xxxgenital herpes
syphilis
gonorrhea
chlamydia
What determines the gender (sex) of a child?
sex chromosomes
Nondisjunction may occur due to ______.
-failure of sister chromatids to separate properly during anaphase II
-failure of homologous chromosomes to separate properly during anaphase I
-failure of centromeres to split apart properly during meiosis II
xxxAll of the listed responses are correct
If embryonic testes do not produce testosterone, a genetic male develops female external genitalia. However, if embryonic testes properly produce testosterone, but a genetic male nevertheless develops female external genitalia, the cause could be ______.
a mutation in the gene that codes for the testosterone receptor