Reproductive System Flashcards
Male-Structure
-urethra is passageway for urine and reproductive fluid (semen)
Essential Organs
- gonads
- pair of testes–>produce sperm and testosterone
Accessory Organs
- passageways/ducts carry sperm from testes to exterior
- additional sex glands provide secretions
- external genitals
Overview
- gametes (sex cells) –>sperm, ova
- sperm and ova fertilize to form zygote
- organs adapted to specific sequence
- production of hormones
Testes-Structure
- located in pouch-like scrotum
- outside of body, below penis
- 1 degree cooler than normal body temperature
- surrounded by tough, whitish membrane (tunica albuginea) which forms lobules
- each lobule consists of narrow, long, coiled seminiferous tubule
- form bulk of testicular tissue mass
- interstitial cells secret testosterone
- each is long duct with central passageway
- sperm develop in walls of tubule
Testes-Function
Spematogenesis
- in seminiferous tubules continually
- sperm stem cells (increase by mitosis)
- Gonadotropin releasing H (GnRH) stimulates ant. pit. to secrete FSH and LH
- undergo meiosis
Testosterone Production
- production stimulated by LH
- masculinization, maintenance of accessory organs, muscular strength and development
Male-Reproductive Ducts
Epididymis
- tightly coiled tube, along top and behind testes
- sperm stored, mature, develop ability to swim
Ductus Deferens
- tube permits sperm to leave epididymis
- encloses blood vessels and nerves
Ejaculatory Duct
-permits sperm to empty into urethra
Urethra
-passes through penis and opens to exterior
Male-Accessory Sex Glands
Semen
- mix of sex cells and secretions
- 3-5ml at one time, each ml contains 100 million sperm
- alkaline to balance acidity of female
Seminal Vesicles
- pouch-like glands, rich in fructose (60%)
- source of energy for sperm
Prostate Gland
- secretes thin, milk-coloured fluid (30%)
- activate sperm and maintain motility
Bulbourethral Gland (Cowper’s)
- before rest, neutralizes residue of acidic urine
- lubricates urethra
Male-External Genitals
Penis
- stiff by filling of tissue with blood during arousal
- enters and deposits sperm
- corpus spongiosum surrounds urethra
- corpora cavernosa lie above (2)
- glans penis is distal end, highly sensitive
Scrotum
- skin-covered pouch suspended from groin
- divides into 2 sacs each containing testis, epididymis, ductus deferens, beginning of spermatic cords
Female-Structure
Essential Organs
- ovaries
- produce ova, estrogens, progesterone
Accessory Organs
- series of ducts extending from ovaries to exterior
- additional sex glands (mammary)
- external genitals
Ovaries-Structure
- attached to ligaments in pelvic cavity
- about 1 million ovarian follicles each have oocyte
- reduced number become primary follicles each with granulosa cell layer
- 350-500 become mature follicles which ovulate and release ovum
- Graafian follicle is a mature ovum in its sac
- follicle ruptures after ovulation and become corpus luteum
Ovaries-Function
Oogenesis
- cytoplasm divided unequally
- one large ovum and 3 small polar bodies
Production of Estrogen and Progesterone
- corpus luteum chiefly secretes progesterone
- Estrogen
- development and maintenance of female secondary sex. char.
- initiation of 1st menstrual cycle
- Progesterone
- produces 11 days after ovulation
- stimulates proliferation of epithelia uterine lining
- acts with estrogen to initiate menstrual cycle
Uterine Tubes
- aka Fallopian tubes/oviducts
- serves as ducts for ovaries
- outer end terminates in expanded, funnel-shaped
- curves over top of each ovary
- inner end attached to uterus, opens into cavity
- some ova never reach tube and remain in ab. cavity
- ectopic pregnancy if fertilized
Uterus
- almost all muscle (myometrium) with small cavity
- body is upper portion
- cervix is lower narrow section
- Fundus
- rounds out to form bulging prominence
- functions in 3 processes
1) Menstruation (endometrium sheds)
2) Pregnancy (endometrium intact)
3) Labour
Vagina
- about 10cm
- mainly smooth muscle
- lined with mucous membrane
- lies in pelvic cavity b/w urinary bladder and rectum
- opens to exterior
Female-Accessory Sex Glands
Bartholin’s Glands
- aka greater vestibular glands
- secretion of lubricating fluid
- open into space b/w labia minora and vestibule
Breasts
- lie over pectoral muscles, attached by connective tissue
- 15-20 divisions (lobes) arranged radially
- several lobules with milk-secreting arranged in clusters
- areola is coloured area around nipple
Female-External Genitals
Mons pubis-skin-covered pad of fat, in hair
Clitoris-erectile tissue
Urethral Orifice-b/w clitoris and vaginal opening
Labia minora-area b/w is vestibule
Hymen-membrane, sometimes partially closes vagina
Orifice-Duct of Bartholin’s open on either side of vagina
Orifice of Vagina
Labia Majora
-elongated folds, fat, pigmented skin
-hair on outer, no hair on inner
