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| 1 | |
An embryo is always stimulated to develop into a female, if it |
| | A) | has at least one X chromosome. |
| | B) | has two X chromosomes. |
| | C) | has an X and a Y chromosome. |
| | D) | lacks a Y chromosome. |
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| 2 | |
All chromosomes except the X and Y chromosomes, are called |
| | A) | homologous chromosomes. |
| | B) | diploid chromosomes. |
| | C) | autosomes. |
| | D) | polysomes. |
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| 3 | |
Barr bodies at the edge of the typical cell nucleus and drumstick appendages in the nuclei of neutrophils from a blood sample represent the |
| | A) | inactive heterochromatin of cells from a female. |
| | B) | active euchromatin of cells from either sex. |
| | C) | parts of a chromosome that become visible during mitosis. |
| | D) | structures seen only during meiosis in spermatogenesis and oogenesis.. |
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| 4 | |
The paramesonephric duct will give rise to the |
| | A) | uterus and uterine tubes. |
| | B) | epididymides, ductus deferens, and ejaculatory ducts. |
| | C) | prostate. |
| | D) | vagina, labia, and clitoris. |
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| 5 | |
For the first 40 days of embryonic development, the gonads have the potential to become either ovaries or testes. The hypothetical substance that determines which of these will occur has been called the |
| | A) | ovary-producing hormone |
| | B) | testis-determining factor |
| | C) | müllerian inhibiting factor |
| | D) | wolffian inhibiting factor |
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| 6 | |
Even in the early development of the male testis, large amounts of male sex hormones, or androgens, such as testosterone are produced by the |
| | A) | Graafian cells. |
| | B) | Sertoli cells. |
| | C) | Leydig cells. |
| | D) | Müllerian cells. |
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| 7 | |
Development of a male fetus depends on suppressing the development of the embryonic ____ and stimulating the development of the ____. |
| | A) | Leydig cells and Sertoli cells, respectively. |
| | B) | müllerian ducts and wolffian ducts, respectively. |
| | C) | urogenital folds and labioscrotal folds, respectively. |
| | D) | genital tubercle and phallus, respectively. |
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| 8 | |
The scrotum of the male and labia majora of the female are said to be homologous structures because they both develop from the _________ of the embryo. |
| | A) | genital tubercle |
| | B) | urogenital sinus |
| | C) | urethral folds |
| | D) | labioscrotal swellings |
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| 9 | |
The function of the enzyme 5α-reductase is to |
| | A) | convert testosterone into the active hormone, dihydrotestosterone. |
| | B) | cause the fetal gonad to develop into a testis. |
| | C) | suppress development of Müllerian duct derivatives. |
| | D) | convert testosterone in the brain to estradiol-17β. |
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| 10 | |
A developmental abnormality, inherited as a recessive trait, that is caused by excessive androgen secretion from the adrenal cortex of the fetus, is called |
| | A) | testicular feminization syndrome |
| | B) | congenital adrenal hyperplasia |
| | C) | hermaphroditism |
| | D) | adrenogenital hypermasculine syndrome |
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| 11 | |
If the developing testes are functioning normally and producing testosterone, yet the embryonic target tissues lack receptors for responding to this hormone, a fetus would develop |
| | A) | ovaries |
| | B) | normal male external genitalia |
| | C) | Klinefelter's syndrome |
| | D) | testicular feminization syndrome |
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| 12 | |
The secretion of luteinizing hormone will be stimulated by |
| | A) | increased inhibin. |
| | B) | decreased gonadotropin releasing hormone. |
| | C) | increased follicle stimulating hormone. |
| | D) | decreased progesterone |
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| 13 | |
Gonadotropoin releasing hormone is a |
| | A) | sex steroid. |
| | B) | hypothalamic hormone. |
| | C) | gonadotropin. |
| | D) | androgen. |
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| 14 | |
Secretion of inhibin by either the Sertoli cells in the seminiferous tubules of the male testes or by the granulosa cells in the female ovarian follicles will specifically decrease the secretion of |
| | A) | FSH. |
| | B) | FSH and LH. |
| | C) | GnRH. |
| | D) | testosterone. |
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| 15 | |
During puberty |
| | A) | LH is the first hormone to demonstrate an increased secretion |
| | B) | GnRH secretion decreases. |
| | C) | the sensitivity of the brain to negative feedback regulation by sex steroids is decreased. |
| | D) | secretion of sex steroids decreases. |
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| 16 | |
In boys testosterone is the only hormone required for all of the following except |
| | A) | growth of the larynx. |
| | B) | development of pubic hair. |
| | C) | growth of the testes. |
| | D) | growth of the penis. |
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| 17 | |
In the testis FSH is only able to directly stimulate |
| | A) | Leydig cells. |
| | B) | granulosa cells. |
| | C) | Sertoli cells. |
| | D) | None of the above choices is correct; FSH only has effects in the ovary. |
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| 18 | |
Amenorrhea |
| | A) | is the age at the first menstrual flow. |
| | B) | may result from obesity. |
| | C) | may occur in women who are very lean and physically active. |
| | D) | is an excessively heavy menstrual flow. |
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| 19 | |
Androgen |
| | A) | are only found in males. |
| | B) | stimulate the development of the Müllerian duct. |
| | C) | stimulate the growth of long bones. |
| | D) | are synthesized in the Sertoli cells. |
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| 20 | |
The earliest haploid cell formed during spermatogenesis is the |
| | A) | primary spermatocyte. |
| | B) | secondary spermatocyte. |
| | C) | spermatogonium. |
| | D) | spermatid. |
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| 21 | |
In the women the arousal phase is characterized by |
| | A) | contraction of the uterus. |
| | B) | the areolae swell and partially hide the nipples. |
| | C) | the clitoris swells. |
| | D) | orgasm occurs. |
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| 22 | |
Until the time of ejaculation, sperm are matured and stored, mainly in the |
| | A) | seminiferous tubules. |
| | B) | epididymis. |
| | C) | vas deferens. |
| | D) | seminal vesicles. |
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| 23 | |
Which of the following is an "erectile tissue" that forms columns extending the length of the penis? |
| | A) | corpus albicans |
| | B) | corpus luteum |
| | C) | corpus cavernosum |
| | D) | corpus callosum |
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| 24 | |
The parasympathetic nervous system causes |
| | A) | erection of the penis. |
| | B) | emission. |
| | C) | ejaculation. |
| | D) | release of secretions from the prostate gland into the semen. |
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| 25 | |
The average ejaculation expels 1.5-5.0 ml of semen, which contains about ____ sperm. |
| | A) | 15-20 million |
| | B) | 45-50 million |
| | C) | 90-750 million |
| | D) | 1.1-1.4 billion |
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| 26 | |
Viagra is effective in treating erectile dysfunction because this drug will |
| | A) | be converted to nitric oxide. |
| | B) | decrease the amount of cyclic AMP in the smooth muscle cells of the penile blood vessels. |
| | C) | decrease the amount of cyclic GMP in the smooth muscle cells of the penile blood vessels. |
| | D) | decrease the activity of phosphodiesterase in the smooth muscle cells of the penile blood vessels. |
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| 27 | |
An ovarian follicle that has multiple layers of granulosa cells that surround the oocyte and has fluid-filled vesicles but no antrum, would be called a(n) |
| | A) | primordial follicle. |
| | B) | primary follicle. |
| | C) | secondary follicle. |
| | D) | graafian follicle. |
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| 28 | |
In oogenesis, meiosis I does not produce two equal-sized daughter cells, but rather forms one large oocyte and one small |
| | A) | oogonium. |
| | B) | ootid. |
| | C) | polar body. |
| | D) | antrum. |
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| 29 | |
An egg cell completes meiosis II |
| | A) | around the fifth month of fetal development. |
| | B) | in the follicular phase of the ovarian cycle. |
| | C) | at the time of fertilization by sperm. |
| | D) | at the time of ovulation. |
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| 30 | |
Ovulation is the process whereby a ____ is released into the uterine tube. |
| | A) | secondary oocyte |
| | B) | secondary oocyte surrounded by the zona pellucida |
| | C) | secondary oocyte, zona pellucida, and corona radiata |
| | D) | secondary oocyte, zona pellucida, corona radiata, and cumulus oophorus |
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| 31 | |
The corpus luteum secretes progesterone in response to |
| | A) | estradiol. |
| | B) | FSH. |
| | C) | LH. |
| | D) | inhibin. |
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| 32 | |
Progesterone levels are highest during the ____ phase of the ovarian or menstrual cycle. |
| | A) | follicular |
| | B) | proliferative |
| | C) | menstrual |
| | D) | luteal |
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| 33 | |
The "surge" in luteinizing hormone secretion from the anterior pituitary that causes ovulation can be partially explained by the |
| | A) | positive feedback of estradiol that increases the release of LH. |
| | B) | graafian follicle growing large enough by this time to secrete large amounts of LH. |
| | C) | rising levels of GnRH causes the graafian follicle to produce more LH receptors. |
| | D) | rising levels of progesterone that exerts a continuous negative feedback effect on the hypothalamus. |
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| 34 | |
Ovulation would be blocked by an antagonist to |
| | A) | luteinizing hormone. |
| | B) | follicle stimulating hormone. |
| | C) | human chorionic gonadotropin . |
| | D) | inhibin. |
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| 35 | |
The secretory phase of the uterus corresponds in time to the ____ phase of the ovary. |
| | A) | luteal |
| | B) | atretic |
| | C) | ovulatory |
| | D) | follicular |
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| 36 | |
Constriction of the spiral arteries and sloughing of the endometrium are characteristic of that event known as |
| | A) | menopause. |
| | B) | menarche. |
| | C) | menstruation. |
| | D) | amenorrhea. |
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| 37 | |
Excessively prolonged menstruation is a condition called |
| | A) | dysmenorrhea |
| | B) | menorrhagia |
| | C) | metrorrhagia |
| | D) | amenorrhea |
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| 38 | |
Before sperm are able to fertilize an egg, they must undergo a process called ____; which normally requires that sperm be present for about seven hours in the female reproductive tract. |
| | A) | spermiogenesis |
| | B) | the acrosomal reaction |
| | C) | capacitation |
| | D) | implantation |
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| 39 | |
A zygote undergoes its first mitotic division or cleavage and becomes a two-celled embryo |
| | A) | about 30-90 minutes after fertilization. |
| | B) | about 30-36 hours after fertilization. |
| | C) | when it arrives in the uterus about four days after ovulation. |
| | D) | when it becomes implanted in the uterine wall about six days after fertilization. |
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| 40 | |
Which of the following arrangements of events is in proper order of occurrence? |
| | A) | acrosomal reaction, decidual reaction, capacitation, implantation, cleavage |
| | B) | acrosomal reaction, capacitation, cleavage, decidual reaction, implantation |
| | C) | capacitation, implantation, cleavage, acrosomal reaction, decidual reaction |
| | D) | capacitation, acrosomal reaction, cleavage, implantation, decidual reaction |
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| 41 | |
The hollow ball that implants in the uterine wall is the |
| | A) | trophoblast. |
| | B) | morula. |
| | C) | frondosum. |
| | D) | blastocyst. |
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| 42 | |
To prevent menstruation and to sustain pregnancy, the trophoblast cells of the implanted embryo must secrete ____ for the first five or six weeks. |
| | A) | progesterone |
| | B) | human chorionic gonadotropin |
| | C) | luteinizing hormone |
| | D) | estrogen |
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| 43 | |
The umbilical arteries |
| | A) | return blood to the maternal vein. |
| | B) | receive blood from the umbilical veins. |
| | C) | return blood to the chorion frondosum. |
| | D) | delivers blood to the chorion frondosum. |
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| 44 | |
An advantage of chorionic villus biopsy over amniocentesis for the diagnosis of genetic diseases is that |
| | A) | it provides more selective sampling of just fetal cells, while amniocentesis samples both fetal and maternal cells. |
| | B) | diagnostic information is available at an earlier stage of fetal development. |
| | C) | it can detect a wider range of genetic and metabolic birth defects than amniocentesis. |
| | D) | it is safer than amniocentesis. |
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| 45 | |
In general, the time for the initiation of labor in humans appears to be set by the |
| | A) | maturity of the fetus. |
| | B) | drop in cholesterol levels in the mother's blood. |
| | C) | increase in glucose levels in the mother's blood. |
| | D) | amount of weight gained by the mother during pregnancy. |
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| 46 | |
The placenta cannot convert cholesterol into androgens and estrogens without the cooperation of enzymes present in the |
| | A) | fetus |
| | B) | chorion |
| | C) | endometrium |
| | D) | blood plasma |
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| 47 | |
Inhibiting the production of _________ produced by the uterus would delay labor. |
| | A) | progesterone |
| | B) | estradiol |
| | C) | prostaglandins |
| | D) | chorionic gonadotropin (hCG) |
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| 48 | |
Milk letdown is a neuroendocrine reflex arc that requires which hormone? |
| | A) | luteinzing hormone |
| | B) | prolactin |
| | C) | oxytocin |
| | D) | dopamine |
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| 49 | |
Breast feeding is thought to inhibit ovulation by directly |
| | A) | inhibiting the secretion of LH. |
| | B) | inhibiting the secretion of GnRH. |
| | C) | stimulating estrogen secretion. |
| | D) | increasing the secretion of inhibin. |
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