chapter 28- reproduction lecture

what are the functions of the reproductive system?

what are the functions of the reproductive system?

produce gametes, hormone production, deliver/receive sperm cells, and nurture a fetus

what is the male gonad?

testes

what is the female gonad?

ovaries

what is the male gamete?

sperm (spermatazoa)

what is the female gamete?

ova (eggs)

which hormone is released from the hypothalamus to help release hormones in the anterior pituitary?

GnRH (gonadotropin releasing hormone)

Which hormones are released from the anterior pituitary to be sent to the gonads?

FSH (follicle-stimulating hormone) and LH (luteinizing hormone)

what hormones are released from the gonads?

Female: estrogen, progesterone and inhibin

Male: testosterone and inhibin

perineum

landmark region in males and females of the pelvic floor

anterior border of the peritoneum?

pubic symphysis

posterior border of periteneum?

coccyx

lateral sides of the periteneum?

ischial tuberosities

anterior triangle of the periteneum?

urogenital triangle

posterior triangle on perineum?

anal triangle

perineal raphe

ridge of skin tissue extending from the anus through the center of the perineum

spermatogenesis

making new sperm (haploid cells)

oogenesis

making new eggs (haploid cells)

Autosomes have…

22 pairs of chromosomes

sex chromosomes have…

1 pair extra, the 23rd pair determines sex (XX female, XY male)

where do the testes form during development?

in the pelvic cavity

how do the testes drop in fetal development?

descend into scrotum through inguinal canal through inguinal ring

scrotum

surrounds and suspends testes, has a medium septum to separate left from right

what is the spermatic cord?

an encasing of nerves, arteries, and muscles the testes needs from the pelvic cavity passing through the inguinal cavity to enter pelvic

what does the spermatic cord surround?

ductus deferens (DAISY)

testicular nerve (TRIES)

testicular artery (TO)

pampiniform venous plexus (PRANK)

cremaster muscle (CALL)

fascia layers (FIONA)

why does the scrotum need to be cooler than the rest of the body?

so spermatogenesis can occur (3*C cooler)

what are the 3 factors that cool the testes

external location

involuntary muscle contraction from the dartos and cremaster muscles

countercurrent heat exchange

how does heat flow in the countercurrent heat exchange of the testicular veins work?

warm arterial blood descends to the testes, but it is surrounded by the cooled off blood from the ascending arteries so heat is lost from the arteries to the veins

tunica albugina

white CT layer surrounding each testis

seminiferous tubules

coiled tubes within each lobe of the testis (specific site of spermatogenesis)

what are the three cell types of the testis

Germ cells (GRACE)

Sustentacular cells (SMELLS)

Interstitial cells (ICKY)

germ cells

future sperm themselves attached to the basement membrane of the tubule

sustentacular cells

form the walls of the tubules, when FSH is released they release ABP (androgen-binding protein) stimulating germ cells to migrate towards lumen, forms blood-testis barrier via tight junctions to protect sperm from white blood cells

interstitial cells

fill up the space surrounding the seminiferous tubule, respond to LH by releasing testosterone

what are the 3 parts of a sperm cell?

head (holds enzymes and chromosomes), mid-piece (holds mitochondria), and tail piece (flagella)

epididymis

coiled tube made up of a head body and tail, sperm are stored and fully matured here

ductus deferens

tube ascending the spermatic cord into the pelvic cavity enlarging into an ampulla

ejaculatory duct

connecter ductus deferens and urethra passing through prostate gland

urethra

passed through the penis (prostatic, membranous, and spongy portions)

penis

has a root, body, glans, and possibly foreskin

what are the two erectile tissues

corpus cavernosum- surrounds testicular artery

corpus spongeiosum- surrounds urethra

what is semen formed by?

accesory glands

seminal vesicles

connects ductus deferense to urethra, 60% of semen

prostate gland

anterior to the rectum, 30% of semen

bulbourethral glands

at the base of the prostate, lubricates urethra and neautralizes the pH if pee came out before, 10% of semen

how much is one ejaculation?

3-5mL of fluid, 300 million sperm cells

what are the 3 contents of semen?

• basic pH- to help sperm motility in acidic vagina

• mucus- for lubrication

• fructose- nutrients for energy for sperm

what do the ovaries hold?

oocytes (immature ova), surrounded by a follicle (turns in to a luteum then albicans)

uterine tube

has a Funnel (holds fimbriae closest to the ovary), Ampulla (site of fertilization), Isthmus (bridge to uterus)

uterus

site of implantation, tilts forward, empties into vagina

uterine fundus

upper domed area

uterine body

main central area

cervix

open area deep to the body

uterine cavity

inferior end of uterus (pap smear)

cervical canal

channel that runs through cervix with mucus glands

internal os

opening between cervix and cervical canal

external os

opening between cervical canal and vagina

what are the 3 uterine layers?

perimetrium- outermost (PINATAS)

myometrium- middle muscle layer (MAY)

endometrium- innermost lining cervical canal (EXPLODE)

vagina

receptable for intercourse, birth canal, menstrual fluid discharged here

fornix

the vaginal “blindspot” around cervix

what is the pH of the vagina

3.5-4, because it is exposed to the environment high pH helps to protect against bacteria

what are the three stages of the ovarian cycle

1. follicular phase (days 1-13): developing follicle will grow as FSH increases, LH increases to cause follicle swelling and then rupture

2. ovulation (day 14): the new oocyte gets released and swept up by the fimbriae

3. luteal phase (days 15-28): follicle turns into corpus luteum which secretes mostly progesterone to thicken uterine lining.It will release some estrogen too as well as inhibin to influence the anterior pituitary to pause follicle development incase of fertilization

what are the stages of the uterine cycle?

1. menses days 1-5: the corpus luteum dies making estrogen and progesterone decrease making the lining of uterus shed

2. proliferative phase days 6-13: estrogen increases allowing for a wet nutrient rich bed to become available for the embryo

3. secretory phase days 14-28: post-ovulation, corpus luteum forming increases progesterone so blood vessels and secretions build up