male reproductive 2

What is the histology of the seminiferous tubules?

have thick, stratified epithelium surrounding central-fluid containing lumen

What does the epithelium of the seminiferous tubules contain?

spheroid spermatogonia embedded in support cells (sertoli cells)

What surrounds each seminiferous tubules?

myoid cells

What are myoid cells?

smooth muscle-like cells that may squeeze sperm and testicular fluids out of the testes

What are interstitial endocrine cells?

located in soft tissue surrounding seminiferous tubules; produce androgens, such as testosterone and secrete it into interstitial fluid

What do the seminiferous tubules consist of?

thick stratified epithelium

What are sustentacular cells (aka. sertoli cells/nurse cells)?

large columnar cells act as supporting cells and play role in sperm formation

What are spermatogenic cells?

cells that are surrounded by sustentocytes and give rise to sperm

What is the scrotum?

sac for testes and associated structures

What divides the scrotum into two compartments?

dartos fascia

How long do males produce sperm?

continuously throughout their lives

What do sperm need to develop correctly?

exactly the appropriate range of temperature to develop correctly (32-35C)

What happens to the sperm if its too hot?

they are malformed

What happens if the sperm are too cold?

they die

What allows for the regulation of temperature of the sperm-producing apparatus?

male scrotum

What is the cremaster muscle?

muscles inside the skin of the sac that can expand and contract as the temperature changes

What is the pampiniform plexus?

veins ascending near testicular artery

What cools arterial blood entering the testes?

countercurrent heat exchanger

What is the function of the cremaster muscle?

pulls testes close to body; continuation of the internal oblique muscle

What is the dartos muscle?

wrinkles skin reducing surface area of scrotum and lifts it upwards

What two things does the urethra convey?

both urine and semen at different time

What are the three regions of the urethra?

prostatic urethra, intermediate part of urethra (membranous urethra), and spongy urethra

What is the prostatic urethra?

surrounded by prostate

What is the membranous urethra?

in urogenital diaphragm

What is the spongy urethra?

runs through penis and opens at external urethra orifice

What is the male copulatory organ?

the penis

What is the male external genitalia?

includes the scrotum and penis

What does the penis consist of?

the root and shaft that ends in the glans penis

What is the prepuce, or foreskin?

cuff of loose skin covering the glans

What is the penis made of internally?

spongy urethra and three cylindrical bodies of erectile tissue

What is the corpus spongiosum?

surrounds urethra and expands to form glans and bulb of penis

What is the corpora cavernosa?

paired dorsal erectile bodies

What is an erection?

erectile tissue fills with blood, causing penis to enlarge and become rigid

Where do the testes descend from during development?

the testes descend from the gonads primitive position high up in the body (abdominal cavity) and end up lying in the scrotum

Why are males more prone to hernias?

because of their descendents from fish, in which the gonads pierce the abdominal wall

What is semen a mixture of?

consist of secretions from the seminiferous tubules, seminal vesicles, prostate and bulbourethral glands

What is the pH of semen?

above 7

Which ANS system controls erection of penis ?

parasympathetic triggers dilation of deep arteries and filling with blood

Which ANS system controls ejaculation?

emission is the sympathetic nervous system, as well as expulsion

Which ANS system controls resolution?

sympathetic signals constrict internal pudendal artery and reduce blood flow to penis

What is the basic pattern of interactions along the hypothalamic-pituitary-gonadal axis?

hypothalamus -> anterior pituitary -> gonads -> target cells

What is the first step in sperm production?

hypothalamus releases gonadotropin-releasing hormone (GnRH)

What is the second step in sperm production?

GnRH binds to anterior pituitary gonadotropic cells, causing them to secrete FSH and LH