Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/20

Click to flip

20 Cards in this Set

  • Front
  • Back
testes descend from abdominal cavity through inguinal canal into scrotum during last months of fetal life
scrotum provides cool environment(optimal for spermatogenesis). the position of the scrotum can vary by spinal reflex mechanism
seminiferous tubules carry out spermatogenesis
leydig cells in the testis secrete testosterone. testosterone secreted into blood, carries by plasma proteins
testosteroe secretion by fetal testis masculinizes reproductive tract and exteral genitalia
secretion at onset of puberty signals growth and maturation of reproductive system
testosterone is essential for spermatogenesis and maintainng male reproductive tract
testosterone: development and maintenance of libido in adult male
testosterone signals development of secondary sexual characteristics like voice change, hair, muscle growth
testosterone's nonrepoductive functions: signals protein anabolism, bone growth at puberty followed by closure of epiphyseal plates.
spermatogenesis produces highly specialized mobile sperm.
spermatozoon=sperm
differentiated , haploid
spermatogonium=undifferentiated, diploid
spermIOgenesis: the packaging (remodeling) of cellular elements of spermatids. includes differentiation into 4 parts: head, acrosome, tail, and midpiece
mitochondria located in midpiece
nucleus is in the head

centriole located between head and midpiece
sertoli cells found in wall of seminiferous tubules. throughout maturation, sperm cells intimately assiciated with sertoli cells
function of sertoli cels: selective transport of materials into the lumen of the tubules. tight junctions between the sertoli cells form a blood-testes barrier (BTB) which allow selective transport of material. sertoli cells provide nourishment for sperm cells (barred by BTB)
sertoli cells function cont:
phagocytosis of cytoplasm extruded during remodeling (destroy defective germ cells), secrete seminiferous tubule fluid into the lumens of the tubules; flushes released sperm into epididymis,secretes androgen-binding protein, maintaining high level of testosterone in lumen which is essential for sperm production, and sertoli cells are also the site of action for spermatogenesis by testosterone and FSH
LH works on leydig cells, causes release of testosterone. FSH works on sertoli cells usual in promoting spermatogenesis
testosterone is essential for mitosis and meiosis of germ cells
there is a higher concentration of testosterone in the testes than the blood due to androgen-binding protein. the high conc. sustains sperm production
FSH: important for spermatid remodeling
estrogen: imp. for spermatogenesis and normal sexuality
-small amount produced by adrenal cortex, and a portion of testosterone secreted by testes converted to estrogen by aromatase (widely distributed in male reproductive tract)
GnRH activity increases at puberty
winding series of tubules in male reproductive tract: transport sperm from the testis to outside the body
accesory glands: secrete fluid into the tract for sperm viability and motility
penis: penetration and deposition of sperm in female
epididymis: attached to the rear of the testis. it is the exit route from the testis to the ductus deferens. here the sperm cells gain ability to move and fertilize. the epididymis concentrates sperm (100X) as they mature
ductus deferens: passes from the scrotal sac up thru the inguinal canal into the abdomen. it is the storage site for concentrated sperm. the two ductus deferens unite behind the bladder forming a V. After bladder, ductus deferens form an ejaculatory duct. ejaculatory duct joins the urethra in the prostate gland under the bladder
male accessory sex glands add to what is ejaculated. they contribute secretions that constitute the bulk of semen.
semen
sex gland secretions, sperm, mucus. provide support for viability of sperm in female reproductive tract, and thereby facilitate fertilization
seminal vesicles: two, which join last part of each ductus deferens
seminal vesicles: supply fructose to nurish ejaculated sperm. secrete prostaglandins which stimulate smooth muscle contraction, helping move sperm. provide bulk of semen. provide precursors (fibrinogen) for clotting of semen.
prostate gland:
single, completely surrounds urethra at neck of bladder
prostate gland:
secretes alkaline fluid that neutralizes acidic vaginal secretions. it also provides clotting enzymes and fibronolysin. cloitting enzymes act on fibrinogen to form fibrin, thus clotting the semen. this keeps the sperm in the vagina during penis withdrawl. fibrinolysin degrades seminal clot, releasing motile sperm within female tract.
bulbourethral glands: two, both empty into urethra just before it enters the penis. it secretes mucus for lubrication for intercourse.
prostaglandins:
locally acting chemical messengers. first discovered in semen. they are fatty acid derivatives found in most tissues. they havea wide variety of effects.
prostaglandin effects:
promoting sperm transport, promoting bronchodilation, increasing renal blood flow, inhibiting hydrochloric acid secretion in the stomach, enhancing cortisol secretion, and cause bursting of follicle so ovulation occurs