Reproductive System, Natalie Perez, P.5

Major Functions of Reproductive System (males and females)

Not active until puberty

Male and female organs different but same 4 functions

  1. Form specialized cells for sexual reproduction (gametes)

Sperm (M)

Ova (eggs) (F)

  1. Bring F & M gametes together through sexual intercourse
  1. Combine genetic info. within gametes through fertilization. Zygote is formed when sperm and egg fuse.
  1. Support development of fetus and birth of baby

Anatomy of Male Reproductive Structures

Primary Sex Organs

Testes: sperm-producing male gonads that lie within scrotum

Tunica Vaginalis: Outer layer derived from peritoneum

Tunica Albuginea: Inner layer forms fibrous capsule

Accessory Reproductive Organs: ducts, glands, & external genitalia

Scrotum: sac of skin & superficial fascia

hangs outside abdominopelvic cavity at root of penis

contains paired testes

Sperm delivered to body through system of ducts

  1. Epididymis: made up of head, body, and tail; where sperm mature
  1. Ductus Deferns: passes through inguinal canal to pelvic cavity
  1. Ejaculatory Duct: Smooth muscle in walls propels sperm from epidermis to urethra
  1. Urethra: during ejaculation , epididymis contracts, expelling sperm out through the urethra

Penis: male copulatory organ

consist of root and shaft that ends in glans penis

Spermatogenesis: process of forming male gametes in seminiferous tubules

Sperm

Head: genetic region; enable sperm to penetrate egg

Midpiece: metabolic region containing mitochondria that produce ATP to move tail

Tail: locomotor region includes flagellum

Anatomy of Female Reproductive Structures

Disorders Associated with Reproductive System

Internal Genitalia: in pelvic cavity; ovaries & duct system (uterine tubes, uterus, & vagina)

External Genitalia: external sex organs

Ovaries: paired structures flank uterus, almond shape (2x bigger)

Ovarian Follicles: tiny saclike structures embedded in cortex. Contain immature egg (oocyte)

Uterine Tubes: AKA Fallopian tubes, receive ovulated oocyte and are usual site of fertilization

Uterus: hollow thick-walled muscular organ. Receives, retains, and nourishes fertilized ovum

Body: major portion

Fondus: rounded superior region

Isthmus: narrowed inferior region

Cervix: narrow neck; projects towards vagina

Cervical Canal: communicates with vagina and uterine body

Uterine wall

Perimetrium: outermost serous layer

Myometrium: bulky middle layer consisting of interlacing layers of smooth muscle

Endometrium: mucosal lining

Mons Pubis: fatty area overlying pubic symphysis

Vagina: Thin-walled tube. Functions as birth canal, passageway for menstrual flow, & organ of copulation

Labia Majora: hair-covered, fatty skin folds

Labia Minora: skin folds lying within labia majora

Vestibule: recess within labia minora

Clitoris: anterior to vestibule

Hormones of the Reproductive System (male and female)

Females Hormones

Estrogen: Promote oogenesis & follicle growth in ovary. Exert anabolic effect on F reproductive tract. Support rapid short-lived growth spurts at puberty. Induce secondary sex characteristics.

Progesterone: works with estrogen to est. and regulate uterine cycle. Promotes changes in cervical mucus. Effects of placental progesterone during pregnancy.

GnRH: stimulates FSH & LH secretion.

FSH: stimulates cells to release estrogen & LH prods other cells to produce androgens, which converts to estrogens

LH: surge triggers ovulation & formation of corpus luteum

FSH * LH stimulate follicles to grow, mature, & secrete sex hormones

Male Hormones

Testosterone: vital in development & function of reproductive organs & other organs/ tissues, sexual behavior, sexual drives

Inhibin: released from gonads in both M&F. Exerts neg. feedback in PSH release from anterior pituitary

Events of Female Hormonal Cycles

Stages of Follicle Development

Phase 1: gonadotropin-independent prenatal phase involves intrafollicular paracrines.

Phase 2: antra phase stimulated by FSH & LH

A primordial follicle becomes primary

Primary follicle becomes secondary follicle

Secondary follicle becomes vesicular follicle

The Ovarian Cycle: monthly series of events associated w/ maturation of egg

Follicular Phase: period of vesicular follicle growth (days 1-14)

Luteal Phase: period of corpus luteum activity (days 14-28)

Ovulation: in between follicular and luteal phase

Ballooning ovary wall ruptures, expelling secondary oocytewith its corona radiata into peritoneal cavity

If no fertilization occurs: oocyte is actually activated 12 months prior to ovulation but mature 14 days before ovulation. Corpus luteum degenerates when LH levels start to fall. Causes sharp decrease in estrogen and progesterone.

Uterine (Menstrual) Cycle: Cyclic series of changes in endometrium that occur in response to fluctuating ovarian hormone levels

Days 1-5: Menstrucal Phase where menstrual flow of blood & tissue lasts 3-5 days. Ovarian hormones at lowest levels

Days 6-14: Proliferative (preovulatory phase) Rising estrogen levels prompt generation of new stratum functionalism layer. Ovulation occurs at end of this phase on day 14

Days 15-28: Secretory (postovulatory) phase Endometrium prepares for embryo to implant

Chlamydia: most common bacterial STI in U.S. Urethritis; penile & vaginal discharges; abdominal, rectal or testicular pain; painful intercourse; irregular menses

Trichomoniasis: parasitic infection that is more common in women than in men. Easily and inexpensively treated

Gonorrhea: Bacterial Infection of mucosal of reproductive & urinary tracts

Syphilis: bacterial infection transmitted sexually or congenitally. Bacteria invades mucosal or even broken skin. Infection = asymptomatic for 2-3 weeks and then is painless

Human Papillomvirus (HPV): cause of genital warts

Genital Herpes: One of the most difficult human pathogens to control because most don't know they are infected

Breast Cancer: Invasive breast cancer = most common malignancy & 2nd most common cause of cancer death in US women