reproductive system

Question 1

functions?

Answer 1

1.produce gametes egg and sperm
2.gonads (testes and ovaries) store gametes and regulate reproduction via hormones
3.testes and ovaries are endocrine glands belong in endocrine and reproductive system

Question 2

what are testes and what do they contain and are organized into?

Answer 2

paired plum size
contain seminferous tubules (sperm factories)
organized into lobules
spermatogenisis occurs here

Question 3

what are the other cells in testes?

Answer 3

sustentacular cells
aka nurse cells or sertoli cells

Question 4

what do nurse cells do?

Answer 4

1.nourish and promote the development of sperm
2. secrete testicular fluid
3. secrete androgen binding protein to create concentration in testes
4. secrete hormone inhibin which inhibits spermatogenisis
5. form blood-testes barriers which are tight junctions between cells protect developing sperm from immune system and regulate tubular fluid contents

Question 5

what are interstitial cells?

Answer 5

leydig cells
1.large cells in interstitial spaces between seminiferous tubules
2. secrete hormone testosterone

Question 6

why are testes located in the scrotum?

Answer 6

temp is 2-4 degress below normal
body temp required for sperm to develop

Question 7

which two muscles regulate testes temperature?

Answer 7

cremaster muscle- skeletal muscle contrats to pull testes closer to body
dartos muscle- smooth muscle in dermis contracts to wrinkle scrotal skin which reduces heat loss

Question 8

what is the duct rete testis?

Answer 8

network of tubules connecting seminiferous tubules with epididymis
some reabsorption of fluid here to concentrate sperm

Question 9

what is the duct epididmysis?

Answer 9

coiled duct on top of each testis approx 20 ft
sperm stored here for 40-60 days
sperm get coated with proteins which makes them non-motile
sperm only become motile once combine with seminal fluid are further activated in female repro tract
smooth muscle in epididymis contracts during ejaculation

Question 10

what is the ductus deferens ?

Answer 10

approx 18 inch in length
lies in spermatic cord which is a tube of fascia containing blood vessels and nerves
passes through a inguinal canal in abdominal wall

Question 11

what is the urethra duct?

Answer 11

duct for urine and semen and is the prostatic urethra and penile urethra
conveys semen from ejaculatory duct to outside

Question 12

what are the accessory glands?

Answer 12

they contribute to the seminal fluid

Question 13

what are the seminal glands?

Answer 13

seminal vesicles
paired and contribute to 60% of semen volume
is a alkaline secretion

Question 14

what does a alkaline secretion contain?

Answer 14

1. fructose which is an energy source for sperm
2. prostaglandins which triggers smooth muscle contraction
3. fibrinogen which coagulates semen
4. substances that enhance sperm motility

Question 15

what is the prostate gland?

Answer 15

single approx size of a walnut in shell encircles urethra
contibutes to 30% of semen volume
contain prostatic fluid

Question 16

what does prostatic fluid contain?

Answer 16

1.l seminalplasmin which is a antibiotic like protein
2. fibrionlysin which breaks down fibrinogen
3. PSA prostate specific antigen helps liquify semen and cervical mucus

Question 17

what are the bulbourethral glands?

Answer 17

cowpers gland
small, paired at the base of the penis
secrete alkaline mucus which is pre-ejaculate to neutralize traces of urine and lubricates tip of penis