Heal session 11-13

Reproductive System

Reproductive system function

Delivery of gametes(egg+sperm)

Production of sex hormone(feminine+masculine)

Protect fetus until birth

Reproductive organ/genital function:

Produce sperm in testes

Produce egg in ovary

Transport gametes to body exterior

Ovary + Testes

Endocrine gland, and reproductive glands or gonads

Puberty

Child→ sexually competent adult

@end individual is capable of producing children

Ages of sexual maturity

Girl;10-14

Boy:12-16

Mitosis

Cell division occurring throughout life. Duplication division AKA exact copies so every cell resulting will have 46 chromosomes too.

Purpose: development, growth + repair

Meiosis

Takes place only in testes +ovary. Called reduction division goes from diploid(46) to haploid(23). Requires two successive divisions meiosis 1+2. Forms gametes and genetic variability

What happens after meiosis?

haploid cells(23) develop into either sperm of 1 egg.

Zygote

fusion of the egg and sperm. Has 46 chromosomes, 23 from egg and 23 from sperm.

Testes

Male gonads/ primary sex organ

Scrotum

sac holding testes

Epididymis

where sperm mature(the little testes hat)

Vas deferens

passes into abdominal cavity bringing sperm into ejaculatory duct→urethra

Seminal vesicle

nutrients and fluid for sperm

Prostate gland

contributes fluid to semen. Surrounds urethra below bladder.

Bulborethral gland

contribute mucus-containing fluid to semen.

Ejaculation process

2 seminal vessicles, prostate gland,+2 bulbourethral glands make semen which is released by the penis

Semen

pH=7.5 slightly basic, fructose sugar is the NRG source for them, contain prostaglandin causing uterus contraction propelling sperm toward egg.

Penis

male organ of intercourse, contains urethra of urinary system. glans penis=enlarged tip of penis, foreskin=skin covering glans penis

Erection mechanics

spongy erectile tissue in shaft. During arousal autonomic nerves release nitric oxide(NO) relaxing blood vessels. Causing cGMP production(relaxes arterial smooth muscle), veins taking blood AWAY from penis r compressed, sphincter closes of bladder.

How many sperm in ejaculation?

300 million 3.5mL of semen

Erectile disfunction

caused by:poor blood flow, medications, illness. Meds like viagra stop the enzyme that breaks down cGMP.

Priapism

persistent +painful erection last over 4 hrs.

Testes development

Develop in abdominal cavity descend into scrotum in last 2 month of fetal development.

Seminiferous tubules:

have lobules(compartments) within the testes. where spermatogenisis happens(sperm production)

Spermatogenesis

Spermatogonia divide into primary spermatocytes(2n)

Primary spermatocytes undergo meiosis 1 to make secondary spermatocytes(n)

Secondary spermatocytes undergo meiosis 2 to make 4 spermatids(n) which develop into sperm.

(takes 74 days)

Sertoli cells

support, nourish+regulate spermatogenesis+produce inhilbin

Inhibin

selectively inhibits FSH secretion from anterior pituitary.

Sperm parts

Head:nucleus covered by acrosome holding enzymes for egg penetration, middle piece:contain mitochondria providing nRG for tail movement, tail(flagellum).

Interstitial/Leydig cells

make androgens(male sex hormones) Ex:testosterone. R between seminiferous tubules.

Male hormonal regulation

hyothalamus secretes GnRH who stimulates FSH+LH.

FSH:promotes sperm production

LH:stimulates testosterone production.

Controlled by negative feedback.

Testosterone, what is it+what does it do?

main male sex hormone.

maintains +starts secondary sex characteristics like height, broad shoulders, deep voice, facial hair, receding hairline, greater muscular development.

Female genetically tract parts(4)

Uterine tubes, Uterus, cervix, vagina.

Ovaries

Female gonads, suspended by 3 ligaments(broad, suspensory+ovarian), site of oogenesis, produces estrogen+progesterone. Regions:fundus,corpus, cervix.

Ligaments holding ovary:

Ovarian ligament holds ovaries to uterus+ suspensory attaches them to the pelvic wall.

Uterine tubes:

(Oviducts, fallopian tubes, salpinges). Have fimbrae to sweep egg into uterine tube(finger like project), funnel is called infundibulum, egg moves toward uterus by ciliary movement.

Egg and sperm life time

Egg lives 6-24hrs, sperm lives 5 days.

Utérus

3 lyrs parametrium, myometrium+endometrium. Uterine tube joins to uterus @fundus, main body is corpus, and cervix enters the vagina.

Endometrium

Supplies nutrients for embryonic+fetal development. Lyrs:functional shed during mentration+basal lyr(multiplying cells)

Endometriosis

Tissues like endometrium is outside the uterus causing chronic inflammation, causing scar tissue production.

Pap test

Screens for cervical cancer by detecting cell changes in te cervix and microscopically examining them.

Hysterectomy+Ovariohysterectomy

Surgical uterus removal.

Ovary and Uterus removal.

Vagina

Folded+stretchy mucosal lining, acidic to prevent bacteria.

Oocyte

Immature egg within a follicle. Females are born with 2mill. Follicles only 500 mature. During ovarian cycle follicle goes from primary -secondary-vesicular follicle.

Ovarian cycle:

Primary follicles:epithelial cells surround (2n)

Secondary follicle:surrounded by follicular fluid+theca cells(n)

Vesicular follicle:fluid-filled cavity balloons out over surface

Ovulation:vesicular follicle bursts releasing oocyte.

The remaining follicle then develops into corpus luteum(gland-like), if not fertilized it disintegrates.

Oogenesis steps

Primary oocyte does meiosis 1=2 haploid cells, one of which is a polar body for holding discarded chromosomes.

Secondary oocyte does meiosis 2 arrested

Which follicles produce which hormones

Primary: estrogen

Secondary:estrogen+some progesterone

Corpus luteum:progesterone+some estrogen

Ovarian cycle hormones:

FSH+LH control ovarian cycle, release of estrogen, progesterone+inhibins.

Inhibin:

Protein secreted by serotonin cells by men and granulosa cells in women. Inhibits FSH, reduces hypothalamic releasing hormone.

Follicular phase

First half of the cycle.FSH promotes primary follicle development who secretes estrogen. Causing negative feedback to control FSH secretion and end follicular phase.

Lutéal phase

LH promotes corpus luteum development which secretes lots of progesterone(some estrogen).

Ménopause

Ovarian cycle stops age 45-55. Ovaries no longer secrete estrogen or progesterone. Complete once menstruation is gone for 1 year.

Uterine cycle(period)

28 day cycle.

Day1-5:menstruation-low estrogen lvls cause endometrium disintegrate and blood vessel rupture.

Day6-13:proliferation phase increased estrogen by new follicles causes thicker endometrium

Day 14:ovulation in ovaries

Day 15=28:secretory phase, more progesterone by corpus luteum thickens endometrium uterine glands mature+produce thick secretion.

Low progesterone causes menstruation.

Zygote, embryo, fetus

Sperm and egg connect.

Mitosis of zygot in uterus makes embryo

Fetus 9th week after conception(or week 11 after last menstrual period).

Menses

Flow of blood and tissues out of the vagina

Implantation

Day 7, signals pregnancy beginning.

Placenta

Sustains developing embryo, made from maternal and fetal tissues. Where the exchange of fetal and maternal blood occurs. Produces HCG which maintains corpus luteum. Pregnancy tests detect HCG lvls in blood(11 days) or urine(15-20days)

Birth control

Active pills (estrogen+progesterone) for 21 days then inactive pills for 7 days. Uterine lining builds up while active pills r taken. Progesterone decreases after last active pill causing menstruation.

Infertility

Failure to become preganant after 1 yr trying. 15% of couples r infertile.

Mâle infertility

Low sperm #, abnormal sperm, sedentary life, smoking, alcohol.

Female infertility:

Overweight women, more leptin impacts GnRH+FSH lvls, uterine tubes blocked by pelvic inflammatory or endometriosis

(AID, IUI, IVF, Intracytoplasmic sperm injection, GIFT,

Artificial insemination by donor:Sperm placed in vagina by doctor.

Intra-utérine insémination.:fertility drugs stimulate ovaries, sperm r placed in uterus can be sorted to get male or female child.

In vitro fer: conception in dish 2-4 days later transferred to uterus.

Intracytoplasmic sperm inj:sperm injected into egg.

Gamete intrafallopian transfer:same as IVF but placed in uterine tubes IMMEDIATELY after brought together.