Chapter 16
Reproduction
Male Anatomy
• Testes
• sperm production
• scrotum
– divided sac of skin
– house testes- olive size
– muscles
» cremaster - move to maintain
temperature
» dartos - move to maintain temperature
At 3 degrees lower than body temp.
• Seminiferous tubules
• sperm made here
• spermatogenesis
–
–
–
–
–
meiosis
primary spermatocytes
4 spermatids
n = 23
initiated by FSH
• mature sperm
• takes 64- 72 days to mature
• cytoplasm becomes compacted into head,
midpiece, and tail
• Conducting tubes
• epididymis
–stores immature sperm,
–takes 20 days for sperm
to transverse through
complete maturation
• vas deferens
–transports sperm to
urethra,
glands secrete fluids
into vas deferens
• urethra
–ejaculation of sperm
• Accessory glands
• seminal vesicles
– 60 % of semen- alkaline
– fructose, vitamin C, and prostaglandins
– yellowish secretions
• prostate gland
– milky fluid with buffer pH 7.5
– 30% of semen
• bulbourethral glands
– cowper’s gland
– thick clear mucus
– cleanses acid in urethra & lubricates penis
– Pre-ejaculatory fluid
• Semen
• sperm + fructose + buffer + other
chemicals
• pH 7.2 - 7.6
• contains a bacterial growth inhibitor
• 2 -5 ml containing 50 - 130 million sperm
per milliliter ejaculated
• Sterile: 20-25 million/ml
• Penis
• anatomy
• erectile tissue
– spongy tissue
– fills with blood
– parasympathetic
• vasocongestion of erectile tissue results in
erection
• ejaculation
– bladder sphincter constricts
– cowper’s gland secretes
– sympathetic spinal reflex nerves
• Testosterone production
• produced by interstitial cells (surround
Seminiferous tubules)
• secondary sex characteristics
–deeper voice
–increased hair growth
–enlargement of skeletal muscles
–thickening of bones
• Ovaries
Female Anatomy
• size of almonds, produces eggs
• contains ovarian follicles
• each follicle contains an immature egg “oocyte”
• Oogenesis
• meiosis
• primary oocytes formed 4 months --> birth
• at puberty each month FSH stimulates a secondary oocyte
to mature into a mature ovum
• LH causes ovulation
• egg and the “corpus luteum” follicle cells are released into
oviduct
• Duct system
• fallopian tubes “oviducts”
– 4 inches long lined with cilia transports egg from
ovary to uterus, fimbriae finger like projections
• uterus
– pear shaped endometrial lining
• vagina
– 3-4 inch tube
– proximal end: cervix - cervical mucus
– distal end: hymen
• external genitalia
•
•
•
•
•
•
vulva
mons pubis
labia
vestibular gland - secrete lubricant
clitoris - erectile tissue
perineum
• Mammary glands
• milk
• menstrual cycle
• 21 - 40 days, ovulation 14 days after onset of
menstruation
• menses
– 1-5 endometrial lining is shed, 1/4 - 1/2 cup,
FSH secreted during these days
– dysmenorrhea
• proliferative stage
– 6-14 rising estrogen levels, thicken endometrium
• ovulation
– day 14, surge of LH, egg is released
• secretory stage
– 15-28, estrogen & rising levels of progesterone
keep endometrium in tact
– no fertilization, progesterone & estrogen levels
fall - start of menses
Pregnancy
• Fertilization
– Must take place in oviducts
• takes sperm 1-2 hours for sperm to complete their
trip
• egg + sperm --> zygote
• 23
23
46
• embryonic development
• fetal development
• effects of the mother
• anatomical
• physiological
– gastrointestinal, urinary, respiratory, cardiovascular
• Childbirth
• parturition
• labor
– dilation
– expulsion
– placental
• contraception
– The pill, condoms, shot, spermicide,
diaphram, nuvaring, abstinence,
• Developmental aspects
•
•
•
•
abnormalities
puberty
menopause - 46-54 yrs
disorders / diseases