male reproductive system

a smooth muscle tube that carries the semen from the epididymis to the penis

ductus deferens

a tube from the ductus deferens to the penis

ejaculatory duct

a muscle-like gland secreting alkaline fluid to neutralize the acids in urine

prostate gland

a protein produced by a gene on the Y chromosome, which results in male primary sex characteristics

testis determining factor (TDF)

male sex hormone secreted by interstitial cells of the testes; results in male primary and secondary sex characteristics

testosterone

secretes fluids to form semen

Cowper's gland

'nurse' cells in the seminiferous tubules that assist in spermatogenesis and produce the hormone inhibin

Sertoli cells

male group of steroid hormones; includes testosterone

androgens

the larger sex chromosome with many more genes than Y

X chromosome

a small sex chromosome that contains the TDF gene; determines maleness of fetus

Y chromosome

-From each testis, sperm are transported to a nearby duct called the epididymis -Within each epididymis, the sperm mature and become motile. -The epididymis is connected to a storage duct called the ductus deferens, which leads to the penis via the ejaculatory duct.

epididymis

a cap on each testicle where sperm are matured and stored prior to ejaculation

epididymis

the ability to produce gametes and reproduce

fertility

a haploid cell made during meiosis that participates in fertilization to make a zygote

gamete

sex organs that produce gametes (sperm or egg); testes in males and ovaries in females

gonads

a hormone produced by Sertoli cells during spermatogenesis that inhibits GnRH, preventing excessive sperm production

inhibin

tightly packed testosterone-secreting cells that surround the seminiferous tubules in the testes

interstitial cells

XY

male sex chromosome

a condition in which there are less than 20 million spermatozoa per millilitre of semen

oligospermia (oligozoospermia)

-the copulatory organ of the male. Its function is to transfers semen to the female. -The penis has a shaft with an enlarged tip called the glans penis -The foreskin surrounds and protects the glans penis. The foreskin does not have any reproductive function. - blood flow increases to specialized erectile tissues in the body and the veins that carry blood away from the penis becomes compressed. This process causes erectile tissues to expand to achieve an erection. -Sperm cells move out of each epididymis through the ductus deferens.

penis

structures that are essential for reproduction

primary sex characteristics

-a pouch of skin located below the penis that holds the testes. -regulates the temperature of the testes. -In the cold, the scrotum draws close to the body(shrivels) to keep testicles warm. -In warm weather the scrotum hangs more loosely to allow the testicles to remain cooler than the body.

scrotum

characteristics that distinguish male from female but are not required for reproduction

secondary sex characteristics

-the ejaculated liquid that contains sperm plus the secretions of the seminal vesicles, prostate, and Cowper's gland. -Semen is combination of sperm cells and fluids.

semen

-As the sperm cells pass through the ductus deferentia, they are mixed with fluids from a series of glands. -The seminal vesicles produce a mucus-like fluid that contains the sugar fructose, which provides energy for the sperm. -The prostate gland and Cowper's gland also secrete mucus-like fluids, as well as an alkaline fluid to neutralize the acids from urine in the urethra. -

seminal fluid

glands producing a fluid containing fructose, which supplies energy for use by sperm

seminal vesicles

-long, coiled, hollow tubes in the testes where sperm are produced. -interstitial cells lie between the seminiferous tubules. -Each testis contains more than 250 m of seminiferous tubules and can produce more than 100 million sperm each day.

seminiferous tubules

Developing sperm are supported and nourished by Sertoli cells, which are also located in the seminiferous tubules.

settle cells

a biochemical compound controlling the development, maintenance, and function of the reproductive system and secondary sex characteristics

sex hormone

-the male gamete. -In sexual reproduction, the haploid sperm contributes half the chromosomes to the zygote; the egg contributes the other half. -sperm reproduction is most successful at temperatures around 35° C. -A mature sperm is a tadpole-shaped structure, about 0.06 mm long. -

sperm

the production of sperm

spermatogenesis

mature sperm stored in the epididymis

spermatozoa

-Each sperm cell has three parts: an oval head, a cylindrical middle piece, and an extended tail. -The head contains a nucleus with 23 chromosomes. It is covered by a cap- like structure called the acrosome. The acrosome stores enzymes that are needed to penetrate the protective layer surrounding a female egg. -The middle piece contains mitochondria, which provide energy for the movement of the tail. -The tail propels the sperm with a lashing motion. The sperm can move at a rate of about 3 mm per hour.

structure/functions of the sperm

-two male gonads that produce sperm and secrete testosterone. - located in the scrotum. - composed of seminiferous tubules, hormone-secreting cells called interstitial cells that lie between the seminiferous tubules.

testes

a pair of male gonads producing sperm and testosterone; also called testes

testicles

-The urethra is a duct that carries fluid through the penis -If sexual arousal continues, semen enters the urethra from the ductus deferentia. -The urethra is shared by the urinary and reproductive systems. (During sexual intercourse, a sphincter tightens to prevent urine from mixing with the semen.) -The movement of semen is the result of a series of interactions between the sympathetic, parasympathetic, and somatic nervous systems. -Sensory stimulation, arousal, and co-ordinated muscular contractions combine to trigger ejaculation.

urethra

the tube leading from the bladder to the penis The urethra may carry either urine or semen.

urethra