male

A&P

Testes

outer tunica vaginalis, inner albuginea

seminiferous tubes

w/in lobules, site of sperm production

sertoli cells

spermatogenic/ sustentocytes: provide nutrients and signals to spermatogenic cells

interstitial endocrine (leidig cells)

produce androgens, testosterone

pampiniform venous plexus

absorb heat from testicular arteries, keep testes cool

scrotum

contain paired testes; lower temp by dartos and cremaster muscle

dartos muscle

smooth; wrinkles skin, pulls scrotum closer to body

cremaster muscle

skeletal; elevates testes

corpus spongiosum

surround urethra and expands to form glans and bulb (penis)

corpus cavernosa

paired dorsal erectile bodies (penis)

duct of epididymis

absorb testicular fluid and pass nutrients to stored sperm

epididymus

mature and store sperm until ejaculation

ductus (vas) deferens

joins w seminal vesicle duct to form ejaculatory duct; smooth muscle propels sperm

seminal glands

sm. muslce contracts during ejaculation; alkaline seminal fluid, 70% vol of semen

bulbo-urethral (cowper) glands

produce thick clear mucous during arousal, lubricates glans and neutralizes trace acidic urine

semen

mix of sperm and accessory gland secretions, alkaline, facilitate sperm movement

erection

sympathetic, sm. muscle relaxes, corpora cavernosa expands

ejaculation

propel semen from duct system; sympathetic, bladder sphincter contracts

spermatogonia

stem cells; type B form spermatocytes

spermatid

nonmotile, haploid

spermiogenesis

spermatids form tail and become spermatozoon (sperm)

head of sperm

acrosome (helmet shape) w/ enzymes to penetrate egg

testosterone in male reproductive

directly prompts spermatogenesis, accessory organs, sex characteristics

androgen binding protein

keeps testosterone secretion high; from anterior pituitary

inhibin

released when sperm count high; dec GnRH/FSH/LH when testosterone high