Mastering A&P 2 CH 27 HW
The muscular layer of the uterine wall is called the __________. epimetrium myometrium endometrium perimetrium
myometrium right answer feedback:The muscular layer of the uterine wall is the myometrium (myo- means "muscle").
Which of the following statements about myoid cells is true? -They form a duct that conveys sperm from the epididymis to the prostate gland. -When they contract, they cause wrinkling of the scrotal skin. -They surround the seminiferous tubules and contract rhythmically to squeeze sperm and testicular fluid through the tubules out of the testes. They elevate the testes.
-They surround the seminiferous tubules and contract rhythmically to squeeze sperm and testicular fluid through the tubules out of the testes. right answer feedback:This is the function of the myoid cells.
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 development of the paramesonephric ducts -a mutation in the gene that codes for the testosterone receptor -hyposecretion of MIF -hypersecretion of MIF
-a mutation in the gene that codes for the testosterone receptor Correct: Testosterone must bind to its receptor to induce the development of male reproductive organs by inducing changes in gene transcription. Return to Assignment
What ovarian structure forms at the beginning of the secretory phase, encouraging its progress, and then degenerates just before menses? -corpus albicans -vesicular follicle -corpus luteum -primary follicle
-corpus luteum Correct: The corpus luteum forms at the beginning of the secretory phase and produces hormones that support the uterus. When it degenerates about 12 days later, the uterus enters menses.
A surge in __________ directly triggers ovulation. -progesterone -estrogen -follicle-stimulating hormone (FSH) -luteinizing hormone (LH)
-luteinizing hormone (LH) Correct When estrogen reaches a certain level in the body, it triggers a positive feedback loop that triggers an LH surge. This triggers ovulation.
The basic difference between spermatogenesis and oogenesis is that __________. -one mature ovum is produced in oogenesis, and four mature sperm are produced in spermatogenesis -spermatogenesis involves mitosis and meiosis, but oogenesis involves meiosis only -the mature ovum is haploid and the sperm is diploid -the mature ovum is diploid and the sperm is haploid -two polar bodies are produced in spermatogenesis
-one mature ovum is produced in oogenesis, and four mature sperm are produced in spermatogenesis right answer feedback:One mature ovum is produced in oogenesis, and four mature sperm are produced in spermatogenesis.
.During the secretory phase of the uterine cycle, __________. -ovulation occurs -the functional layer of the endometrium regenerates -the endometrium is shed -the endometrium prepares for implantation
-the endometrium prepares for implantation Correct Secretions in the endometrium during the secretory phase aide in implantation.
In a typical or "average" cycle, ovulation occurs on day __________. 1 5 14 21 28
14 right answer feedback:In a typical cycle, ovulation occurs on day 14.
The number of chromosomes in a human gamete is __________; this is referred to as a __________ chromosome number. -23;haploid -23; diploid -46; haploid -46; haploid
23; haploid
The diploid chromosomes number in humans is -12 -23 -24 -46
46 The normal chromosome number in most body cells is referred to as the diploid chromosome number. In humans, this number is 46. The number of chromosomes in gametes is called the haploid number. The haploid number is half the diploid number. Thus, in humans, the haploid chromosome number is 23.
During the preschool examination of a 4-year-old boy, you are unable to palpate his testes within the scrotal sac. His parents state that previous exams have been normal, and that the testes are clearly visible during baths. What is the most likely explanation? -A chilly examination room or your cold hands have activated the cremasteric reflex. -The testes may have migrated back up into the boy's abdomen since the last examination. -Because he does not trust you, the boy is deliberately causing his testes to retract close to his body. -The parents' observations are probably incorrect.
A chilly examination room or your cold hands have activated the cremasteric reflex. Correct The cremaster muscles elevate the testes, pulling them higher in the scrotum in response to cold temperatures.
What is the role of estrogen on luteinizing hormone (LH) production? -Estrogen levels have no effect on LH production. -Estrogen may have either an inhibitory or an excitatory effect on LH production depending on the overall estrogen levels. -Estrogen only has an excitatory effect on LH release so that as estrogen levels increase, there will always be a corresponding increase in LH levels. -Estrogen only inhibits LH production so that as estrogen levels increase, there will always be a corresponding decrease in LH levels. Submit
Estrogen may have either an inhibitory or an excitatory effect on LH production depending on the overall estrogen levels. Correct Estrogen exerts negative feedback on LH production until estrogen levels reach a certain concentration, and then estrogen exerts positive feedback on LH production, which promotes ovulation.
After DNA replication, each individual chromosome becomes a homologous pair. -True -False
False Correct After DNA replication, each chromosome is composed of two sister chromatids.
The ovaries are situated retroperitoneally next to the kidneys. True False
False The ovaries are situated in the peritoneal cavity flanking the uterus.
The main component of semen is sperm.
False. Sperm is actually a minor component of seminal fluid. Most (about 70%) of semen fluid volume is attributed to secretions of the seminal vesicles. The prostate gland and bulbourethral glands also contribute to seminal fluid. The urethra does not add anything to seminal fluid.
Which of the following represents the order in which reproductive hormones are secreted in males? FSH, GnRH, LH, testosterone LH, GnRH, FSH, testosterone GnRH, LH/FSH, testosterone, inhibin FSH, GnRH, testosterone, LH FSH, LH, GnRH, testosterone
GnRH, LH/FSH, testosterone, inhibin right answer feedback:The hypothalamic-pituitary-gonadal axis regulates the production of gametes and sex hormones in males.
__________ stimulates the anterior pituitary to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Inhibin Progesterone Gonadotropin-releasing hormone estrogen
Gonadotropin-releasing hormone Gonadotropin-releasing hormone (GnRH) stimulates the anterior pituitary to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). In females, progesterone, estrogen, and inhibin discourage the secretion of FSH and LH.
__________ acts upon the __________ to encourage the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Testosterone; anterior pituitary Testosterone; sustentocytes Gonadotropin-releasing hormone (GnRH); anterior pituitary Gonadotropin-releasing hormone (GnRH); sustentocytes
Gonadotropin-releasing hormone (GnRH); anterior pituitary Gonadotropin-releasing hormone (GnRH) acts upon the anterior pituitary to encourage the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH).In males, FSH stimulates sustentocytes (Sertoli cells) to produce androgen-binding protein (ABP). In response to rising LH levels, testosterone is produced by interstitial endocrine cells.
What is the role of the granulosa cells in the ovarian cycle? -Granulosa cells become the secondary oocyte once the antrum is formed. -Granulosa cells guide the development of the oocyte. -Granulosa cells release LH to trigger ovulation. -Granulosa cells produce progesterone. Submit
Granulosa cells guide the development of the oocyte. Correct Granulosa cells are directly connected to the oocyte by gap junctions, allowing for direct communication between the oocyte and granular cells. These cells guide each other's development.
Choose the FALSE statement about oogenesis. In oogenesis, three polar bodies and one functional gamete are produced. In humans, the secondary oocyte must complete meiosis II before it can be fertilized. Oogenesis occurs in the ovaries. Primary oocytes are stalled in prophase I until puberty.
In humans, the secondary oocyte must complete meiosis II before it can be fertilized. Female infants are born with primary oocytes that are stalled in prophase I until puberty. At the onset of puberty, each month, one primary oocyte continues with meiosis I. 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.
Match the phases of meiosis to the events that occur in each phase. Using the drop-down menus, match each numbered item on the left with a lettered item on the right. telophase I---> two genetically unique haploid cells are formed metaphase I ---> tetrads align randomly along the cell's equator prophase I ---> crossovers form anaphase I ---> homologous chromosomes separate from one another telophase II ---> four genetically unique haploid cells are formed
In prophase I, crossing over occurs between replicated homologous chromosomes. Tetrads align randomly at the metaphase plate during metaphase I. During anaphase I, homologous chromosomes separate but sister chromatids remain together. Following telophase I, two genetically unique haploid cells are formed. After telophase II, four genetically unique haploid cells are formed.
Which of the following is an effect of luteinizing hormone (LH) after ovulation? -It inhibits the formation of secretory glands in the mucosal endometrium during the secretive stage. -It maintains the corpus luteum. -It stimulates production of a new functional layer of the endometrium. -It thins the cervical plug to facilitate the passage of sperm. Submit
It maintains the corpus luteum. Correct LH maintains the corpus luteum. Increased levels of estrogen promote the release of LH at ovulation, but the increased levels of progesterone after ovulation inhibit the release of LH, which causes the degradation of the corpus luteum.
What is the fate of the corpus luteum if pregnancy occurs? -It secretes progesterone and some estrogen for about three months. -It produces progesterone and some estrogen for about 10 days and then degrades. -It continues to stimulate the development of the oocyte until ovulation can occur. -It implants into the uterine wall to begin pregnancy. Submit
It secretes progesterone and some estrogen for about three months. Correct It implants into the uterine wall to begin pregnancy. Submit
Which hormone stimulates the ruptured ovarian follicle to become the corpus luteum? FSH GnRH estrogen LH
LH right answer feedback:As indicated by its name, luteinizing hormone stimulates the ruptured ovarian follicle to become the corpus luteum, which will secrete large quantities of progesterone to maintain the stratum functionalis in case conception occurs.
Which of the following is true about meiosis? Meiosis is how most cells in the body divide. Meiosis produces cells that have a haploid chromosome number. Meiosis leads to the production of genetically identical cells. Meiosis involves only one cell division event.
Meiosis produces cells that have a haploid chromosome number. Meiosis is used to produce haploid gametes. Most body cells divide by mitosis, not meiosis. Unlike mitosis, meiosis involves two rounds of cell division. Meiosis leads to the production of four genetically unique cells.
Which of the following hormones is NOT involved in the regulation of the number of sperm produced in the testes? testosterone gonadotropin-releasing hormone PSA inhibin
PSA right answer feedback:PSA is a prostate cancer marker and is not involved in the regulation of spermatogenesis.
Why are the male testes located in the scrotum, outside the abdominopelvic cavity? -The testes begin their development outside of the abdominopelvic region. -Spermatogenesis is temperature sensitive. -Their external location is necessary for penile development. -Their external location influences the development of male secondary sexual characteristics.
Spermatogenesis is temperature sensitive. Correct Spermatogenesis, the production and maturation of sperm, requires a temperature lower than core body temperature.
Which of the following differentiates the follicular and luteal phases of the ovarian cycle? -The luteal phase occurs directly before ovulation while estrogen levels are high, and the follicular phase occurs directly after ovulation when estrogen levels drop. -The follicular phase is the period during which the follicle secretes estrogen, and the luteal phase is when the follicle secretes luteinizing hormone. -The follicular phase occurs directly before ovulation, and the luteal phase occurs directly after ovulation. -The follicular phase ends with a peak in progesterone production that triggers ovulation and the start of the luteal phase.
The follicular phase occurs directly before ovulation, and the luteal phase occurs directly after ovulation. Correct The follicular phase is the period in which the dominant follicle prepares for ovulation and secretes large amounts of estrogen. The luteal phase occurs after ovulation as the corpus luteum secretes progesterone and some estrogen.
What is the main difference between oogenesis and spermatogenesis in terms of meiosis? -Oogenesis produces three polar bodies, while spermatogenesis produces only one. -Oogenesis does not include a second meiotic division. -Oogenesis takes place in the uterus, while spermatogenesis takes place in gonadal tissue. -The number of functional gametes produced is different.
The number of functional gametes produced is different. Correct In spermatogenesis, four functional gametes are produced, while oogenesis produces only one functional gamete because of the loss of three polar bodies.
What is the most common bacterial sexually transmitted disease in the United States? genital warts chlamydia syphilis vaginitis gonorrhea
chlamydia right answer feedback:Chlamydia is the most common bacterial sexually transmitted disease in the United States.
Match the following. Using the drop-down menus, match each numbered item on the left with a lettered item on the right. Uterus -> receives, retains, and nourishes a fertilized ovum fimbriae->fingerlike projections that brush over the ovary uterine (fallopian) tubes->generally the site of fertilization of the ovulate oocyte vagina -> thin-walled structure that connects the uterus to the body exterior ovaries -> house and form the female gametes
The ovaries are the primary sex organs in females: They produce and store the female gametes. The uterine (fallopian) tubes are generally the site of fertilization of the ovulated oocyte. Since the uterine tubes are not directly connected to the ovaries, the ends of the tubes that are near the ovaries are equipped with fimbriae. Fimbriae are fingerlike projections that brush over the ovary to sweep ovulated eggs into the uterine tubes. The fertilized ovum is received, retained, and nourished by the uterus. The inferior end of the uterus is called the cervix; it connects the body of the uterus to the vagina. The vagina is a thin-walled structure that connects the uterus to the body exterior.
Which of the following is FALSE regarding the vagina of an adult female? -The vagina is also called the birth canal. -The pH of the adult vagina is alkaline. -The vaginal mucosa lacks glands. -The mucosa of the vagina is stratified squamous epithelium.
The pH of the adult vagina is alkaline. Correct The pH of the vagina is acidic
Match the following. Using the drop-down menus, match each numbered item on the left with a lettered item on the right. tunica albuginea-->fibrous capsule of the testes seminiferous tubules ---> site of sperm production in the testes epididymis ---> site of sperm storage pampiniform venous plexus-->cools arterial blood to keep the testes below core temperature interstitial endocrine cells---> make testosterone
The production of sperm is optimal at about 3°C below core body temperature. The pampiniform venous plexus is an adaptation that cools arterial blood that is being delivered to the testes to keep them below core temperature.Each testicle is surrounded by two layers (tunics). The outer tunic is the two-layered tunica vaginalis. Deep to this serous layer is the tunica albuginea, which is the fibrous capsule of the testis.The production of sperm occurs in the seminiferous tubules, which are packed into the lobules of the testis. Surrounding each seminiferous tubule are three to five layers of smooth muscle-like myoid cells. By contracting, these cells help to squeeze sperm and testicular fluids through the tubules and out of the testes. Sperm are stored in the epididymis.Sperm production requires testosterone. Testosterone is produced in the testes by interstitial endocrine cells (Leydig cells).
Why does only one egg, rather than four eggs, develop during oogenesis, given that spermatogenesis results in four sperm formed from one stem cell? -Once formed, spermatids, but not oocytes, undergo additional rounds of division by mitosis. -Only one egg can be fertilized at a time. -Unequal cytoplasmic division ensures that a fertilized egg has ample nutrients for its journey to the uterus. -The egg does not go through the meiotic division processes that the sperm undergo.
Unequal cytoplasmic division ensures that a fertilized egg has ample nutrients for its journey to the uterus. Correct 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. Lacking nutrient-containing cytoplasm, the polar bodies degenerate and die. This is very different than the result of sperm formation.
Which of the following is NOT produced by meiosis? - a sperm cell -a liver cell -an egg, or ovum - all of the given choices are produced by meiosis
a liver cell Correct Liver cells are somatic cells, and they are all produced by mitosis, not by meiosis.
The pH of the adult female vagina is normally __________. neutral basic acidic alkaline
acidic The pH of the adult vagina is acidic. This is because bacteria in the vagina ferment glycogen to form lactic acid. This acidity protects the vagina from a number of pathogens.In adolescents, the vaginal fluid tends to be alkaline (basic). Question
Which portion of the sperm contains the enzymes needed to penetrate the oocyte? -midpiece -acrosome -head -tail
acrosome Correct The acrosome contains the hydrolytic enzymes needed to digest the zona pellucida on the oocyte.
Which of the following might be reported by a man with benign prostatic hypertrophy (BPH)? -feeling of the bladder is full, even just after urinating -having to strain to urinate -pain after ejaculation or during urination -All of the above
all of the above Correct Use your textbook to review the anatomy of the prostate gland, bladder and urethra to understand how the function of these organs can be impacted by BPH.
The __________ of the mammary glands are responsible for producing milk during lactation. lactiferous sinuses lactiferous ducts alveoli areolae
alveoli The lobules of the mammary glands contain glandular alveoli that are responsible for milk production when a woman is lactating. The alveoli then pass the milk they produce to the lactiferous ducts, which open to the outside at the nipple. Just deep to the areola, each lactiferous duct has a dilated region called a lactiferous sinus, where milk accumulates during nursing.
At which point in the uterine cycle are the ovarian hormone levels at their lowest? -at the beginning of the proliferative phase -about one week after ovulation -at the beginning of the menstrual phase -at ovulation
at the beginning of the menstrual phase Correct The ovarian hormone levels are lowest at the beginning of the menstrual phase. Their low levels are what trigger menstruation.
When does ovulation occur in the uterine cycle? -at the end of the secretory phase -at the end of the proliferative phse -at the end of the luteal phase -at the end of the menstrual period
at the end of the proliferative phase Correct A surge in luteinizing hormone triggers ovulation at the end of the proliferative phase of the uterine cycle, around day 14.
The sperm's acrosome __________. provides motility contains enzymes provides the blood testis barrier has a high density of mitochondria contains nutrients
contains enzymes right answer feedback:The acrosome contains enzymes that allow the sperm to penetrate the egg.
Within the ovary, progesterone is produced by the __________. secondary follicles tertiary follicles corpus albicans primary follicles corpus luteum
corpus luteum right answer feedback:Within the ovary, progesterone is produced by the corpus luteum.
The functional layer of the endometrium is shed in response to __________. increased progesterone levels increased estrogen levels decreased progesterone levels decreased estrogen levels
decreased progesterone levels feedback:The endometrium has two layers: the stratum functionalis and the stratum basalis. The stratum functionalis (or functional layer of the endometrium) is shed during menstruation in response to declining levels of progesterone. During the proliferative phase of the uterine cycle, the stratum basalis will regenerate the stratum functionalis.
Which of the following is NOT an effect of testosterone? stimulates maturation of male sex organs maintains male libido maintains male secondary sex characteristics decreases sperm production
decreases sperm production Testosterone stimulates sperm cell production, promotes the development of male secondary sex characteristics, maintains male libido, and stimulates maturation of male sex organs.
When does the total number of chromosomes get reduced from 46 pairs to 23 individual chromosomes? during mitosis during metaphase II during meiosis I during interphase
during meiosis I Correct Chromosome pairs are separated during anaphase I, and this first division is called the "reduction division."
In terms of the male sexual response, parasympathetic stimulation causes __________. ejaculation fertilization the penis to become flaccid spermiogenesis erection of the penis
erection of the penis right answer feedback:Parasympathetic stimulation causes NO to be released, causing penile arterioles to dilate, allowing the erectile bodies to fill with blood.
Which hormone is responsible for the development of secondary sex characteristics found in women? estrogen prolactin LH progesterone FSH
esetrogen
Meiosis results in __________. two identical diploid cells two nonidentical haploid cells four identical diploid cells four nonidentical diploid cells four nonidentical haploid cells
foru nonidentical haploid cells Correct: Meiosis is the processes by which genetically unique haploid gametes are formed.
Meiosis starts with a single diploid cell and produces -eight haploid cells -two haploid cells -four diploid cells -two diploid cells -four haploid cells
four haploid cells Correct Meiosis produces four haploid cells.
Which of the following is a likely result of meiosis? -two eggs, each with 23 chromosomes -two eggs, each with 46 chromosomes -four sperm, each with 23 chromosomes -four sperm, each with 46 chromosomes
four sperm, each with 23 chromosomes Correct In males, meiosis produces four sperm, each with 23 chromosomes.
The uterine layer shed with each monthly cycle is the __________. perimetrium basal layer of endometrium functional layer of endometrium tunica albuginea myometrium
functional layer of endometrium right answer feedback:The uterine layer shed with each monthly cycle is the functional layer of endometrium. This innermost layer is shed when hormone levels drop at the end of the monthly cycle.
During prophase I of meiosis, -chromosome pairs are positioned in the middle of the cell. -there are two daughter cells, each with 23 chromosomes. -there are four haploid daughter cells. -the homologous chromosomes separate and move towards opposite poles. -homologous chromosomes stick together in pairs. Submit
homologous chromosomes stick together in pairs. Correct Homologous chromosomes stick together in pairs during prophase I.
In response to warmth, the scrotum __________. increases its surface area pulls the testes closer to the body becomes heavily wrinkled decreases blood flow to the testes
increases its surface area Viable sperm cannot be produced in abundance at core body temperature (37°C). The superficial location of the scrotum, which holds the testes, provides a temperature about 3°C lower than core temperature, allowing viable sperm to be produced.The scrotum is affected by temperature changes. When it is cold, the scrotum reduces its surface area by becoming heavily wrinkled; it also shortens to pull the testes closer to the body wall. In warm temperatures, the scrotum becomes flaccid and loose to increase its surface area, and hangs lower to keep the testes away from the warmer body trunk.
A cell preparing to undergo meiosis duplicates its chromosomes during -meiosis II -prophase I -interphase -metaphase I -anaphase I
interphase Correct Chromosomes are duplicated during interphase.
__________ cells, located between seminiferous tubules, produce testosterone. Follicle Myometrial Thalamic Interstitial Sustentacular
interstitial right answer feedback:Interstitial, or Leydig cells, produce testosterone.
In males, which of the following includes the correct atrget and result of LH stimulation -sustentocytes: increased testosterone -sustentocytes: increased spermatogenesis -interstitial cells: increased androgen-binding protein (ABP) secretions -interstitial cells: increased androgen secretions
interstitial cells: increased androgen secretions Correct In males, LH targets interstitial cells. As a result of LH stimulation of interstitial cells, the levels of androgens, such as testosterone, increase.
Which of the following are MISMATCHED? luteal phase; characterized by decreased progesterone levels ovulation; release of a secondary oocyte ovarian cycle; monthly series of events associated with maturation of an egg follicular phase; development of a secondary oocyte within a dominant follicle right answer feedback:
luteal phase; characterized by decreased progesterone levels The ovarian cycle includes the monthly events that are associated with the maturation of an egg. The ovarian cycle includes the follicular phase, ovulation, and the luteal phase. During the follicular phase, a secondary oocyte develops within a dominant follicle. During ovulation, the secondary oocyte is released from the ovary. After ovulation, the ruptured follicle in the ovary collapses and the remaining granulosa cells are modified into an endocrine structure called the corpus luteum. The corpus luteum secretes progesterone and some estrogen.
Which hormone is most responsible for triggering ovulation? -progesterone -estrogen -follicle-stimulating hormone (FSH) -luteinizing hormone (LH)
luteinizing hormone (LH) Correct Estrogen levels increase during the follicular phase, which triggers a surge of LH. This surge of LH triggers ovulation.
Which of these meiosis stages is functionally the most similar to mitosis? -meiosis I -meiosis II -meiosis I with II -neither meiosis I nor II
meiosis II Correct Meiosis II is fundamentally identical to mitosis. Prophase II, anaphase II, metaphase II, and telophase II have the same events as their corresponding stages in mitosis.
During what phase of the female's uterine cycle is the uterine lining shed? -secretory of postovulatory, phase -preovulatory phase -menstrual phase -proliferative phase
menstrual phase Correct: The functional layer of the endometrium is shed during days 1 through 5 of the uterine cycle, a process called menses or menstruation.
The area of the sperm cell that contains many mitochondria is the __________. tail acrosome midpiece head
midpiece The head of the sperm contains the cell's nucleus. Atop the nucleus is a package of enzymes called the acrosome. The enzymes in the acrosome allow the sperm cell to penetrate the egg. The sperm midpiece contains many mitochondria spiraled tightly around the contractile filament of the tail. The main role of the mitochondria is to provide energy for motility.
The organ that makes estrogen and progesterone is the __________. ovary pineal gland vestibular gland vagina hypothalamus
ovary right answer feedback:The ovaries, which make estrogen and progesterone, are the primary sex organs of the female.
The surge in LH that occurs during the middle of the ovarian cycle triggers __________. FSH release activation of primordial follicles menstruation ovulation uterine-lining secretion
ovulation right answer feedback:The surge in LH that occurs during the middle of the ovarian cycle triggers ovulation, which occurs, on average, on day 14 of the monthly cycle.
When estrogen reaches a certain level in the body, it triggers a positive feedback loop that triggers an LH surge. This triggers ovulation. -stratum functionalis is shed -glandular secretions commence -menstruation begins -ovulation occurs
ovulation occurs Correct When estrogen reaches a certain level in the body, it triggers a positive feedback loop that triggers an LH surge. This triggers ovulation.
If a male undergoes a vasectomy, which of the following can no longer take place? -passage of sperm cells from the rete testes to the epididymis duct -passage of sperm cells from the seminiferous tubules to the rete testes -passage of sperm cells from the epididymis duct to the epididymis tail -passage of sperm cells from the epididymis to the urethra
passage of sperm cells from the epididymis to the urethra Correct Since the ductus (vas) deferens is severed during a vasectomy, sperm cells can no longer pass from the epididymis to the penis.
Which male structure is homologous to the female's clitoris? -pubis -scrotum -prostate gland -epididymis -penis
penis right answer feedback:Like the clitoris, the penis has erectile tissues.
Which portion of the penis is removed during circumcision? -prepuce (foreskin) -bulb of the penis -glans penis -crus of the penis
prepuce (foreskin) Correct The prepuce, or foreskin, forms a covering of the glans penis and is removed during circumcision. This procedure may confer some health benefits, particularly in cases of chronic infection, and is also a common religious practice.
In which uterine phase does the functional layer of the endometrium start to rebuild? preovulatory ovulation menstrual secretory proliferative right answer feedback:
proliferative right answer feedback:The functional layer of the endometrium starts to rebuild in the proliferative phase, which is initiated by rising estrogen levels.
Genetic variation of individual chromosomes occurs during __________. -metaphase I -anaphase I -prophase I -prophase II
prophase I Correct During prophase I, genetic recombination can occur as arms of homologous chromosomes become spliced with one another.
Chromosomes can exchange genetic information during a process called "crossing over." This occurs when homologous chromosomes are lined up in pairs. When does this happen? -metaphase II -prophase I -anaphase I anaphase II
prophase I Correct During prophase I, homologous chromosomes align with each other and undergo crossing over.
During meiosis, segments of nonsister chromatids can trade places. This recombination of maternal and paternal genetic material is a key feature of meiosis. During what phase of meiosis does recombination occur? -prophase I -Metaphase I -anaphase I -telophase I -meiosis II
prophase I Correct Segments of nonsister chromatids trade places during prophase I, resulting in recombination.
At what point during meiosis do homologous chromosomes pair up? -metaphase I -anaphase I -prophase II -prophase I
prophase I Correct The key event in meiosis, the pairing of homologous chromosomes, happens in prophase I. This sets the stage for halving the amount of DNA during the first cellular division.
The correct order of events during meiosis is -metaphase I, prophase I, telophase I, anaphase I, cytokinesis, meiosis II. -prophase I, anaphase I, metaphase I, telophase I, meiosis II, cytokinesis. -prophase I, anaphase I, telophase I, metaphase I, meiosis II. -prophase I, metaphase I, anaphase I, telophase I, cytokinesis, meiosis II. -metaphase I, prophase I, anaphase I, telophase I, cytokinesis, meiosis II.
prophase I, metaphase I, anaphase I, telophase I, cytokinesis, meiosis II. Correct Meiosis starts with prophase I and continues with metaphase I, anaphase I, telophase I, and cytokinesis. This is followed by meiosis II.
Although effective in treating erectile dysfunction, Viagra has the side effect of reducing systemic blood pressure by causing ______. -a reduction in cardiac output -a reduction in parasympathetic stimulation of penile arterioles -relaxation of muscle tissue in arteries -decreased blood flow to the ventricular walls
relaxation of muscle tissue in arteries Correct Smooth muscle relaxation would lead to vasodilatation of arteries. Remember that blood pressure is directly affected by blood vessel diameter.
Which cell type is ovulated from the ovary? ovum oogonium primary oocyte secondary oocyte tertiary oocyte
secondary oocyte right answer feedback:Secondary oocytes are ovulated from the ovary. Females do not ovulate true egg cells. The secondary oocyte does not complete meiosis II and become a true ovum until a sperm penetrates the cell.
Which of the following structures produces the greatest amount of the secretions found in semen? -prostate -seminal glands -bulbo-urethral glands -epididymis
seminal glands Correct The secretions of the seminal glands account for some 70% of semen volume and function to increase sperm motility and fertilizing ability.
Which of the following shows the correct pathway for sperm cells as they leave the testes? -seminiferous tubule, rete testis, epididymis, ductus deferens -ductus deferens, epididymis, rete testis, seminiferous tubule, -ductus deferens, epididymis, seminiferous tubule, rete testis -rete testis, seminiferous tubule, epididymis, ductus deferens
seminiferous tubule, rete testis, epididymis, ductus deferens Correct This is the correct pathway. Sperm are stored in the tail of the epididymis until they are ejaculated. If they are not ejaculated, they will eventually break down and be phagocytized.
Sperm is produced in the __________. -ejaculatory duct -epididymis -ductus deferens -seminiferous tubules
seminiferous tubules Correct Sperm are made in the seminiferous tubules. Rather, fluid flow in the seminiferous tubules carries sperm as they are made toward an exit point from the testis.
Sperm are produced in the __________. seminiferous tubules prostate gland seminal gland spermatic cord interstitial cells epididymis
seminiferous tubules right answer feedback:Seminiferous tubules are coiled tubes within the testes that function in sperm production.
In order, list the structures sperm will pass through from the testes to the external urethral orifice. -epididymis, seminiferous tubules, ampulla, vas deferens, prostatic urethra, ejaculatory duct, spongy urethra -epididymis, ampulla, seminiferous tubules, vas deferens, spongy urethra, prostatic urethra, ejaculatory duct -seminiferous tubules, epididymis, vas deferens, ampulla, ejaculatory duct, prostatic urethra, spongy urethra ejaculatory duct, epididymis, -seminiferous tubules, vas deferens, spongy urethra, prostatic urethra, ampulla
seminiferous tubules, epididymis, vas deferens, ampulla, ejaculatory duct, prostatic urethra, spongy urethra right answer feedback:Sperm are produced in the seminiferous tubule and exit via the urethra.
Conversion of haploid spermatids to functional sperm is specifically called __________. spermatogenesis meiosis spermiogenesis mitosis
spermiogenesis During spermiogenesis, spermatids are converted to functional sperm: The spermatids lose excess cytoplasm, elongate, and form a tail. The resulting sperm (spermatozoa) have a head, midpiece, and tail.
Which of the following structures makes up most of the male urethral length? spongy urethra membranous urethra prostatic urethra ejaculatory duct
spongy urethra right answer feedback:The spongy urethra makes up 75% of the male urethra.
The __________ is shed during menstruation. stratum basalis stratum functionalis perimetrium myometrium
stratum functionalis The uterine wall has three layers: the perimetrium, myometrium, and endometrium. The endometrium has two layers: the stratum functionalis and the stratum basalis. The stratum functionalis (or functional layer of the endometrium) is shed during menstruation in response to declining levels of progesterone. During the proliferative phase of the uterine cycle, the stratum basalis will regenerate the stratum functionalis.
Which layer of the uterus is the site for implantation of a fertilized egg? -stratum functionalis of the endometrium -myometrium -stratum basalis of the endometrium -perimetrium
stratum functionalis of the endometrium Correct Implantation occurs at the stratum functionalis, the innermost layer of the uterus.
What is the testicular target for follicle-stimulating hormone (FSH) -sustentocytes (Sertoli cells) -spermatozoa -interstitial endocrine cells (Leydig cells) -spermatogonia
sustentocytes (Sertoli cells) Correct Sustentocytes in the walls of the seminiferous tubules respond to FSH by releasing androgen-binding protein, which maintains high testosterone levels near developing sperm cells.
The primary sex organ(s) of the male is/are the __________. prostate epididymis testes penis seminal vesicle
testes right answer feedback:The testes are the primary sex organs of males; they are also called gonads.
Which of the following is considered a primary sex organ in males? scrotum penis testes prostate gland
testes wrong answer feedback:The primary sex organs, or gonads, are the organs responsible for gamete production. In males, the testes are the gamete-producing organs; in females, the ovaries accomplish this important function. The remaining structures of the reproductive system are called accessory reproductive organs.
During anaphase I, what structures separate and move to opposite poles of the cell? nucleoli tetrads nonhomologous chromosomes sister chromatids right answer feedback:
tetrads right answer feedback:The tetrads, composed of replicated homologous chromosomes, will separate and migrate to the poles of the cell during anaphase I.
Which of the following structures help(s) to keep the testes at a cool temperature? the interstitial endocrine cells the rete testis the testicular arteries the pampiniform plexus
the pampiniform plexus right answer feedback:The pampiniform plexus absorbs heat from testicular arteries, cooling the arterial blood before it enters the testes.
Which of the following structures passes through the inguinal canal? the prostatic urethra the ejaculatory duct the epididymis the spermatic cord
the spermatic cord right answer feedback:The spermatic cord passes through the inguinal canal.
Which statement about vasectomies is FALSE? They involve a minor surgical procedure. The part of the ductus deferens that lies in the scrotum is cut. They are a highly effective method of birth control. They are approximately 10% reversible.
they are approximately 10% reversible right answer feedback:Approximately 50% of vasectomies are reversible.
What is the function of the blood testis barrier? -to prevent activation of the immune system of the male against the developing sperm -to provide only select nutrients to the developing sperm -to ensure that semen contains only sperm and seminal fluid -to filter out male sex hormones Submit
to prevent activation of the immune system of the male against the developing sperm Correct: A male's immune system would identify sperm as foreign bodies. The blood testis barrier formed by sustentocytes in seminiferous tubules prevents that interaction.
What is the function of meiosis? to produce four cells, each with identical chromosomes to produce cells with double the chromosome number of the original cell to produce cells with half the chromosome number of the original spermatogonium or oogonium to produce genetically identical cells through the two nuclear divisions
to produce cells with half the chromosome number of the original spermatogonium or oogonium Correct Sperm and egg cells have half the chromosome number of the spermatogonium or oogonium. This is necessary so that they can combine to form a 2n zygote.
The reason that the testes are suspended in the scrotum is to __________. to provide a cooler temperature protect sperm from the immune system to reduce the chance of infection from the enteric bacteria place sperm storage sites nearer to the penis create extra space for the sex organs
to provide a cooler temperature right answer feedback:Spermatogenesis requires a cooler temperature than the core body temperature.
What part of the female system is the usual site of fertilization of the ovulated oocyte? -cervical canal -uterine (fallopian tube) -vagina -uterus
uterine (fallopian) tube Correct Eggs that successfully implant in the uterus are first fertilized in the uterine tube. This does not imply a "tubal pregnancy," where the zygote implants in the uterine tube.
The usual site of fertilization is the __________. ovary uterus vulva uterine tube vagina
uterine tube right answer feedback:The usual site of fertilization is the uterine, or fallopian, tube.
Which of the following is an incorrect matching of female reproductive structures with their functions? -vagina; birth control -ovarian follicle: ovum (egg) production -uterus: fertilization of ovum by sperm -uterine tube; transport ovum to uterus
uterus: fertilization of ovum by sperm Correct The uterine tube is the location where fertilization generally occurs. The uterus (womb) is the organ that receives, retains, and nourishes the fertilized ovum during pregnancy.
