064 Male Reproductive Physiology

Question 1

Normal testosterone and sperm production depends on the pulsatile secretion of hypothalamic __and __ and __ from the anterior pituitary gland.

Answer 1

Normal testosterone and sperm production depends on the pulsatile secretion of hypothalamic GnRH and LH and FSH from the anterior pituitary gland.

Question 2

Regulation of hypothalamic-pituitary-gonadal (HPG) axis hormones occurs primarily through __.

Answer 2

Regulation of hypothalamic-pituitary-gonadal (HPG) axis hormones occurs primarily through NEGATIVE FEEDBACK.

Question 3

The determination of maleness is derived from the __ on the Y chromosome. However, developmental genes such as __ and __ are considered antitestis genes and can proactively induce female gonadal development.

Answer 3

The determination of maleness is derived from the SRY GENE on the Y chromosome. However, developmental genes such as WNT4 and DAX1 are considered antitestis genes and can proactively induce female gonadal development.

Question 4

Changes to the HPG axis with paternal age include __, __, and __.

Answer 4

Changes to the HPG axis with paternal age include LOWER TESTOSTERONE LEVELS, BLUNTED AXIS FEEDBACK, and IRREGULAR HORMONE PULSATILITY.

Question 5

The testis contains __ of seminiferous tubules and __ Leydig cells in the young adult.

Answer 5

The testis contains 250 m of seminiferous tubules and 700 million Leydig cells in the young adult.

Question 6

__ occurs in stages, cycles, and waves to ensure constant sperm production.

Answer 6

SPERMATOGENESIS occurs in stages, cycles, and waves to ensure constant sperm production.

Question 7

Genes on the X as well as the Y chromosome govern spermatogenesis and contribute to __.

Answer 7

Genes on the X as well as the Y chromosome govern spermatogenesis and contribute to MALE INFERTILITY.

Question 8

With paternal age, there are increases in __, __, and __ leading to disease in offspring.

Answer 8

With paternal age, there are increases in SPERM STRUCTURAL CHROMOSOMAL ABNORMALITIES, AUTOSOMAL DOMINANT MUTATIONS, and EPIGENETIC ALTERATIONS leading to disease in offspring.

Question 9

The __ consists of principal cells with absorptive and secretory function, basal cells derived from macrophages, and contractile cells that facilitate sperm transport.

Answer 9

The EPIDIDYMIS consists of principal cells with absorptive and secretory function, basal cells derived from macrophages, and contractile cells that facilitate sperm transport.

Question 10

During epididymal passage, sperm mature by gaining progressive __ and the ability to __ the egg zona pellucida.

Answer 10

During epididymal passage, sperm mature by gaining progressive MOTILITY and the ability to BIND TO AND PENETRATE the egg zona pellucida.

Question 11

Epididymal function is __, important considerations for cryptorchidism, varicocele, and 5α-reductase use.

Answer 11

Epididymal function is TEMPERATURE AND ANDROGEN DEPENDENT, important considerations for cryptorchidism, varicocele, and 5α-reductase use.

Question 12

The vas deferens is of __ origin and serves to transport sperm from the cauda epididymis to the ejaculatory duct during seminal emission.

Answer 12

The vas deferens is of WOLFFIAN (MESONEPHRIC) DUCT origin and serves to transport sperm from the cauda epididymis to the ejaculatory duct during seminal emission.

Question 13

The seminal vesicle and ejaculatory duct unit is analogous to the __and __ and is subject to both physical blockage and functional disorders that result in infertility.

Answer 13

The seminal vesicle and ejaculatory duct unit is analogous to the BLADDER and URETHRA and is subject to both physical blockage and functional disorders that result in infertility.

Question 14

Sperm are ciliated cells that possess a “__” axonemal structure that allows motility.

Answer 14

Sperm are ciliated cells that possess a “9 + 2” axonemal structure that allows motility.

Question 15

It is estimated that __ genes regulate sperm motility.

Answer 15

It is estimated that 200 to 300 genes regulate sperm motility.

Question 16

Sperm motility defects, termed __, are common and can be either correctable (nonspecific flagellar anomalies) or genetic (dysplasia of the fibrous sheath).

Answer 16

Sperm motility defects, termed CILIARY DYSKINESIAS, are common and can be either correctable (nonspecific flagellar anomalies) or genetic (dysplasia of the fibrous sheath).

Question 17

__ is a circular, histone- and intron-free DNA ring that encodes for respiratory-chain–complex proteins and is very susceptible to mutations.

Answer 17

HUMAN SPERM mtDNA is a circular, histone- and intron-free DNA ring that encodes for respiratory-chain–complex proteins and is very susceptible to mutations.