chapter 27- male reproductive system

What is the main difference between oogenesis and spermatogenesis in terms of meiosis?

A. Oogenesis produces three polar bodies, while spermatogenesis produces only one.

B. Oogenesis does not include a second meiotic division.

C. Oogenesis takes place in the uterus, while spermatogenesis takes place in gonadal tissue.

D. The number of functional gametes produced is different.

D

Select the statement below that is FALSE.

A. Meiosis results in haploid cells while mitosis results in diploid cells.

B. Meiosis occurs only after the onset of puberty while mitosis occurs throughout an entire lifetime.

C. A cell undergoing meiosis results in 4 cells while a cell undergoing mitosis results in 2 cells.

D. Meiosis produces genetically unique cells while mitosis produces genetically identical cells.

B

The diploid number of chromosomes in a human is 46. Therefore, the number of chromosomes in a primary spermatocyte or primary oocyte is ________.

A. 46

B. 92

C. 23

D. 38

A

Which of the following cells is released during ovulation?

A. secondary oocyte

B. ovum

C. primary oocyte

D. oogonium

A

Which of these is true regarding primary oocytes?

A. They contain chromosomal tetrads.

B. They begin to form in a female ovary at puberty.

C. They are basically the same things as oogonia.

D. They are haploid.

A

Why does only one egg, rather than four eggs, develop during oogenesis, given that spermatogenesis results in four sperm formed from one stem cell?

A. Unequal cytoplasmic division ensures that a fertilized egg has ample nutrients for its journey to the uterus.

B. Once formed, spermatids, but not oocytes, undergo additional rounds of division by mitosis.

C. The egg does not go through the meiotic division processes that the sperm undergo.

D. Only one egg can be fertilized at a time.

A

Human egg and sperm are similar in that ________.

A. they have the same number of chromosomes

B. they have the same degree of motility

C. they are about the same size

D. about the same number of each is produced per month

A

The basic difference between spermatogenesis and oogenesis is that ________.

A. during spermatogenesis two more polar bodies are produced

B. the mature ovum is n, while the sperm is 2n

C. in oogenesis, one mature ovum is produced from the parent cell, and in spermatogenesis four mature sperm are produced from the parent cell

D. spermatogenesis involves mitosis and meiosis, but oogenesis involves meiosis only

C

Occasionally three polar bodies are found clinging to the mature ovum. One came from an unequal division of the ovum, but from where did the other two arise?

A. The first polar body has also divided to produce two polar bodies.

B. One is an undeveloped primary oocyte that failed to mature.

C. What you really see are two polar bodies and the sperm that will fertilize the egg.

D. There were originally four polar bodies and one disappeared.

A

The smaller cell produced by oogenesis meiosis I, called the first polar body, is essentially a packet of discarded nuclear material

T or F

T

Spermatogenesis ________.

A. involves a kind of cell division limited to the gametes

B. results in the formation of diploid cells

C. is the process of releasing mature sperm cells into the lumen of the seminiferous tubule

D. involves a two-part process called mitosis I and mitosis II

A

Which of the following is the final product of spermiogenesis?

A. secondary spermatocytes

B. type B daughter cells

C. spermatids

D. spermatozoa

D

Which of these cells would contain 23 chromosomes?

A. early spermatids

B. spermatogonia

C. type B daughter cells

D. primary spermatocytes

A

Which of the following cells remains at the basal lamina to continue the pool of dividing germ cells?

A. type A daughter cells

B. type B daughter cells

C. primary spermatocytes

D. secondary spermatocytes

A

Meiosis starts with a single diploid cell and produces

A. four haploid cells.

B. eight haploid cells.

C. four diploid cells.

D. two diploid cells.

E. two haploid cells.

A

A cell preparing to undergo meiosis duplicates its chromosomes during

A. anaphase I.

B. prophase I.

C. meiosis II.

D. interphase.

E. metaphase I.

D

During prophase I of meiosis,

A. the homologous chromosomes separate and move towards opposite poles.

B. there are four haploid daughter cells.

C. chromosome pairs are positioned in the middle of the cell.

D. homologous chromosomes stick together in pairs.

E. there are two daughter cells, each with 23 chromosomes.

D

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?

A. prophase I.

B. meiosis II.

C. telophase I.

D. anaphase I.

E. Metaphase I.

A

What is the function of the blood testis barrier?

A. to filter out male sex hormones

B. to provide only select nutrients to the developing sperm

C. to prevent activation of the immune system of the male against the developing sperm

D. to ensure that semen contains only sperm and seminal fluid

C

Which of the following would most directly interfere with sperm production?

A. ingestion of a substance that mimicked inhibin

B. interruption of sustentocytes' production of ABP

C. low sperm count

D. use of synthetic steroids (testosterone

B

Which portion of the sperm contains the enzymes needed to penetrate the oocyte?

A. midpiece

B. acrosome

C. tail

D. head

B

A varicocele is an abnormal enlargement of veins in the pampiniform plexus which may hinder blood flow through the pampiniform venous plexus into the testicular vein. The reduced venous drainage and the resulting elevated testicular temperature may be caused by ______.

A. defective venous valves in the testis

B. elevated systemic arterial blood pressure

C. elevated core body temperature

D. reduced testicular arterial blood flow

A

All but one of the following statements are true regarding the differences between early and late spermatids. Select the answer below that does NOT reflect a difference between early and late spermatids.

A. Early spermatids have not formed flagella.

B. Early spermatids are round and have excessive cytoplasm.

C. Early spermatids have not undergone spermiogenesis.

D. Early spermatids have not undergone meiosis and are still diploid.

D

During spermiogenesis ________.

A. the acrosome migrates towards the posterior end of the spermatid because of its ability to propel the flagella moving the sperm through the female reproductive system towards the egg

B. the acrosome migrates towards the posterior end of the spermatid because its hydrolytic enzymes will be needed for digestion of the excessive cytoplasm around the flagella of the developing sperm

C. the acrosome migrates towards the anterior end of the spermatid because its pointy shape helps the sperm to move more efficiently

D. the acrosome migrates towards the anterior end of the spermatid because its hydrolytic enzymes will be needed for penetration when the sperm contacts the egg during fertilization

D

All but one of the events described below occur during spermiogenesis. Select the event that does NOT occur during spermiogenesis.

A. Mitochondrial DNA is packaged into the nucleus to be delivered to the egg during fertilization.

B. The centrioles migrate to the posterior end of the developing sperm to form the microtubules that make up the flagellum.

C. Excessive cytoplasm will be shed to reduce unneeded mass of the maturing sperm.

D. Mitochondria form around the proximal end of the flagellum. They will provide the ATP to drive the motion of the flagellum.

A

All but one of the following statements is true with regard to the blood testis barrier. Select the one statement that is FALSE.

A. The barrier marks the border between the basal compartment and the adluminal compartment.

B. The cells that form the blood testis barrier are joined by tight junctions.

C. The barrier is made up of astrocytes that surround blood vessels in the testis.

D. The barrier prevents the spermatocytes from exposing their unique antigens to the immune system.

C

The cells that produce testosterone in the testis are called ________.

A. spermatocytes

B. interstitial endocrine cells

C. sustentacular cells

D. spermatogonia

B

Which of the following statements about spermatogenesis is NOT true?

A. The secondary spermatocytes each form two spermatids.

B. The spermatogonium forms the primary spermatocyte.

C. Each spermatid forms two sperm.

D. The primary spermatocyte forms two secondary spermatocytes.

C

A boy who has not passed through puberty sustains an injury to his anterior pituitary such that FSH is no longer released, but LH is normal. After he grows to maturity, one would expect that he would ________.

A. be unable to produce viable sperm

B. not develop secondary sex characteristics

C. be impotent (unable to have an erection)

D. have impaired function of interstitial cells

A

Which of the following is NOT produced by meiosis?

A. a liver cell

B. an egg, or ovum

C. a sperm cell

D. All of the given choices are produced by meiosis.

A

When does the total number of chromosomes get reduced from 46 pairs to 23 individual chromosomes?

A. during metaphase II

B. during interphase

C. during meiosis I

D. during mitosis

C

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?

A. anaphase II

B. prophase I

C. metaphase II

D. anaphase I

B

After DNA replication, each individual chromosome becomes a homologous pair.

T or F

F

Which of the following is a likely result of meiosis?

A. four sperm, each with 46 chromosomes

B. four sperm, each with 23 chromosomes

C. two eggs, each with 23 chromosomes

D. two eggs, each with 46 chromosomes

B

Which of the following shows the correct pathway for sperm cells as they leave the testes?

A. ductus deferens, epididymis, seminiferous tubule, rete testis

B. seminiferous tubule, rete testis, epididymis, ductus deferens

C. rete testis, seminiferous tubule, epididymis, ductus deferens

D. ductus deferens, epididymis, rete testis, seminiferous tubule,

B

If a male undergoes a vasectomy, which of the following can no longer take place?

A. passage of sperm cells from the rete testes to the epididymis duct

B. passage of sperm cells from the epididymis duct to the epididymis tail

C. passage of sperm cells from the seminiferous tubules to the rete testes

D. passage of sperm cells from the epididymis to the urethra

D

Why are the male testes located in the scrotum, outside the abdominopelvic cavity?

A. Spermatogenesis is temperature sensitive.

B. Their external location influences the development of male secondary sexual characteristics.

C. The testes begin their development outside of the abdominopelvic region.

D. Their external location is necessary for penile development.

A

Sperm is produced in the __________.

A. epididymis

B. ductus deferens

C. ejaculatory duct

D. seminiferous tubules

D

A man who has had a successful orchiectomy may still be able to have children because ______.

A. the remaining testis is able, by itself, to produce a sufficient amount of testosterone

B. the seminiferous tubules of the remaining testis are still active

C. the epididymis posterior to the remaining testis is still functional

D. All of the listed responses are correct.

D

The dartos and cremaster muscles are important to the integrity of the male reproductive system. Which of the following best describes the role they play?

A. They regulate the temperature of the testes.

B. They contract to allow ejaculation.

C. They contract to push sperm along the ductus deferens.

D. They are responsible for penile erection.

A

The most important risk for testicular cancer in young males is ________.

A. failure of the testis to make their normal descent

B. a diet high in fat

C. smoking

D. sexually transmitted infections

A

When it is cold, the scrotum is pulled away from the body.

T or F

F

A scrotal muscle that contracts in response to cold environmental temperature is the cremaster.

T or F

T

Which male reproductive structure is NOT correctly matched with its function?

A. seminal vesicles: produce semen

B. epididymis: produce sperm

C. bulbourethral gland: neutralize urethra before ejaculation

D. ductus deferens: carry sperm toward ejaculation

B

Why doesn't semen enter the urinary bladder during ejaculation?A.Ejaculation is a parasympathetic reflex that activates urinary contraction muscles.

B. The smooth muscle sphincter at the base of the urinary bladder closes.

C. There is no urge to urinate during sexual intercourse because of the suppression of LH by testosterone buildup in the blood.

D. There is no common duct between the reproductive system and the urinary system.

B

Which of these male accessory ducts transports both sperm cells and urine?

A. urethra

B. ductus (vas) deferens

C. epididymis

D. ejaculatory duct

A

Prostate cancer is ________.

A. often the result of a distortion of the urethra

B. the number one cause of death in men

C. sometimes a slow-growing cancer that may never represent a threat to the patient

D. most common in Asians

C

Which of the following structures produces the greatest amount of the secretions found in semen?

A. prostate

B. epididymis

C. seminal glands

D. bulbo-urethral glands

C

Which gland is NOT matched with its type of secretion?

A. urethra: clear, viscous mucus that neutralizes urine

B. prostate gland: milky, acidic semen

C. seminal vesicles: 70% of seminal volume

D. bulbourethral glands: lubricating secretion

A

Which of the following might be reported by a man with benign prostatic hypertrophy (BPH)?

A. feeling the bladder is full, even just after urinating

B. having to strain to urinate

C. pain after ejaculation or during urination

D. All of the above.

D

The ability of sperm cells to move along the ductus deferens is due to ________.

A. peristaltic contractions

B. hormonal action

C. gravity

D. enzymatic activity

A

Which of the following glands are responsible for producing 70% of semen volume?

A. the pituitary

B. the seminal vesicles

C. the prostate

D. the bulbourethral glands

B

The secretions of the bulbourethral glands neutralize traces of acidic urine in the urethra and serve as a lubricant during sexual intercourse.

T or F

T

Erection of the penis results from ________.

A. parasympathetic activation of the bulbourethral glands

B. dilation of the veins in the penis

C. a parasympathetic reflex that promotes release of nitric oxide

D. a sympathetic activation of bulbospongiosus muscles

C

Which of the following is the result of meiosis during spermatogenesis?

A. formation of flagellum

B. shedding of excess cytoplasm

C. formation of semen

D. production of haploid cells

D

Male erection is a response to a parasympathetic reflex, and ejaculation is a response to a sympathetic reflex.

T or F

T

Sperm are ejaculated from the corpora cavernosa of the penis.

T or F

F

Which of the choices below is NOT a function of testosterone?A.stimulates the HPG axis

B. stimulates protein synthesis

C. contributes to male sexual behavior and spermatogenesis

D. stimulates the male pattern of development

A

Which of the following is true of testosterone?

A. The release of testosterone surges during ejaculation.

B. Testosterone provides positive feedback on gonadotropin release.

C. Testosterone is produced by interstitial endocrine cells.

D. The production of testosterone is stimulated by FSH.

C

Which of the following reduces circulating blood levels of follicle-stimulating hormone (FSH) when the sperm count is high?

A. androgen-binding protein (ABP)

B. estradiol

C. inhibin

D. luteinizing hormone (LH)

C

Which hormone promotes the formation of male secondary sex characteristics such as the appearance of pubic, axillary, and facial hair; enhanced hair growth on the chest; and a deepening voice?

A. follicle-stimulating hormone (FSH)

B. luteinizing hormone (LH)

C. gonadotropin-releasing hormone (GnRH)

D. testosterone

D

In males, which of the following includes the correct target and result of LH stimulation?

A. interstitial cells: increased androgen secretions

B. sustentocytes: increased testosterone

C. sustentocytes: increased spermatogenesis

D. interstitial cells: increased androgen-binding protein (ABP) secretions

A

The release of __________ encourages sustentocytes to release __________.

A. luteinizing hormone; testosterone

B. luteinizing hormone; androgen-binding protein

C. follicle-stimulating hormone; androgen-binding protein

D. inhibin; testosterone

C

Which of the following hormones controls the release of anterior pituitary gonadotropins?

A. GnRH

B. FSH

C. testosterone

D. LH

A

Which male hormone provides negative feedback for the secretion of FSH?

A. ACTH

B. inhibin

C. GnRH

D. ICSH

B

Which of the choices below is NOT a part of the hypothalamic-pituitary-gonadal axis?

A. interstitial cells

B. hypothalamus

C. anterior pituitary gland

D. thalamus

D

The hypothalamic-pituitary-gonadal axis ________.

A. involves posterior pituitary release of two regulating hormones

B. involves FSH and LH release from the anterior pituitary

C. involves positive feedback control of spermatogenesis

D. involves the release of testosterone from the anterior pituitary

B

A low secretion of luteinizing hormone (LH) in the normal male adult would cause ________.

A. excessive beard growth

B. shrinkage of the anterior pituitary gland

C. decreased testosterone secretion

D. increased spermatogenesis

C

The amount of testosterone and sperm produced by the testes is dependent on the influence of FSH alone.

T or F

F

Male testicular functions are regulated by FSH and LH.

T or F

T

What hormone, produced in the anterior pituitary gland, works in conjunction with gonadal steroids to promote bone development in males?

A. Follicle-stimulating hormone

B. Growth hormone

C. Prolactin

D. Luteinizing hormone

D

The constancy of the chromosome number for an organism from one generation to the next is maintained through ________.

A. mitosis

B. DNA synthesis

C. cytokinesis

D. meiosis

D

Select the statement which is FALSE.

A. Further genetic variation typically does not occur after meiosis I.

B. Meiosis II is essentially the same process as mitosis except the starting cells are haploid (n).

C. Meiosis II is essentially the same process as mitosis except the genetic material will not replicate before division takes place.

D. Crossing over is a source of genetic variability seen in meiosis while independent assortment is a source of genetic variability seen in mitosis.

D

What is the function of meiosis?

A. to produce four cells, each with identical chromosomes

B. to produce genetically identical cells through the two nuclear divisions

C. to produce cells with half the chromosome number of the original spermatogonium or oogonium

D. to produce cells with double the chromosome number of the original cell

C

At what point during meiosis do homologous chromosomes pair up?

A. prophase II

B. anaphase I

C. metaphase I

D. prophase I

D

Which of these meiosis stages is functionally the most similar to mitosis?

A. meiosis I

B. meiosis II

C. meiosis I with II

D. neither meiosis I nor II

B

Which of the following is considered a role of primary sex organs?A.secretions for copulation

B. site of fertilization

C. production of sex hormones

D. copulation

C

The number of chromosomes in a human gamete is __________; this is referred to as a __________ chromosome number.

A. 23; haploid

B. 23; diploid

C. 46; haploid

D. 46; diploid

A

All of the following things occur during meiosis I. Select the statement below that does NOT occur during meiosis I.

A. A single diploid (2n) nucleus has become two haploid (n) nuclei.

B. The homologous chromosomes are separated from each other.

C. The sister chromatids are separated from each other.

D. Portions of maternal chromosomes crossover with equivalent portions of paternal chromosomes.

C

Which of the following statements is true of metaphase I of meiosis I?A. The sister chromatids line up randomly on the spindle equator with some maternal and paternal chromatids on both sides of the equator.

B. Joined homologous pair uniformly line up on the equatorial spindle with chromosome one at the top and chromosome 23 on the bottom.

C. Homologous pairs align randomly on the spindle equator with a mix of paternal and maternal homologs destined for each of the daughter cells.

D. Tetrads align randomly on the spindle equator with all the maternal homologs on one side and all the paternal homologs on the opposite side

C

Select the statement which is true regarding independent assortment.

A. It only occurs in meiosis II.

B. Its effects are significant in meiosis and in mitosis.

C. It is a significant source of genetic variation only during meiosis I.

D. It is a significant source of genetic variation that occurs in meiosis I and meiosis II.

C

If gametes were diploid like somatic cells, how many chromosomes would the zygote contain?

A. Half the diploid number with no change in development.

B. Triple the diploid number, and with every succeeding generation, the chromosome number would continue to triple and normal development would not occur.

C. Twice the diploid number, and with every succeeding generation, the chromosome number would continue to double and normal development could not occur.

D. There is no relationship between gametes and somatic cells.

C

The stage in meiosis where chromosomal exchange takes place is telophase I.

T or F

F