Unit 11 - Reproductive Physiology Flashcards
Achievement of Pregnancy
Sperm, Ovum, Healthy environment, normally functioning hormone pathways
Sperm
head (consists primarily of the nucleusDNA)
acrsome (enzyme-filled vesicle that caps tip of the head, used to penetrate ovum)
Midpiece (area where mitochondria are concentrated)
Tail (provides mobility for spermatozoan)
Male reproductive functions
Production of sperm
delivery of sperm to female
female reproductive functions
production of ova
reception of sperm
transport of sperm and ovum to common site for union (fertilization or conception)
maintenance of the developing fetus until it can survive in outside world (pregnancy)
Giving birth to the baby (parturition)
nourishing infant after birth by milk production (lactation)
Female reproductive organs
Ovaries, oviducts, uterus
Ovaries
primary female reproductive organs
produce ova
secrete female sex hormones
oviducts
pick up ova ovulation
serve as site for fertilization
uterus
maintenance of fetus during development
expelling fetus at end of pregnancy
Ovarian cycle two phases
follicular phase and luteal phase
Follicular phase
first half of cycle
increased amounts of estrogen
rapid follicular growth (mature about 14 days)
follicle ruptures to release oocyte from ovary (ovulation)
oocyte enters oviducts (it may or may not be fertilized)
Luteal phase
last 14 days of ovarian cycle
old follicular cells transform to corpus luteum
secretes progesterone along with smaller amounts of estrogen
converts endometrium to highly vascularized, glycogen filled tissue
1. If released ovum is not fertilized corpus luteum degenerates within about 14 days
2. if ovum -> corpus luteum becomes corpus luteum of pregnancy
oviduct
ovum transport to oviduct (must within 24 after ovulation)
sperm deposited in vagina travel through cervical canal, uterus, and to upper third of oviduct (female reproductive tract aids in sperm migration) contractions of myometrium, upward contractions of oviduct smooth muscle, allurin released by mature eggs
Accessory Sex Glands
seminal vesicles, prostate gland, bulbourethral gland
Seminal Vesicles
supply fructose for energy
supply prostaglandins (promote smooth muscle movement (enhances sperm transport)
secrete fibrinogen
Prostate gland
contributes alkaline fluid that neutralizes acidic vaginal secretions
provides clotting enzymes and fibrinolysin
Bulbourethral glands
release lubricating mucus
Fertilization
First sperm to reach ovum
Fuses with plasma membrane of ovum
triggers chemical change in ovum’s surrounding membrane that makes outer layer impermeable to entry of more sperm
Head of sperm gradually pulled into ovum’s cytoplasm
within hour, sperm and egg nuclei fuse fertilized ovum now called a zygote
ovum and sperm transport to the site of fertilization
complication : ectopic pregnancy
Blastocyst
fertilized ovum divides mitotically (within week grows and differentiates into blastocyst capable of implantation)
blastocyst implants in endometrial lining with the help of enzymes released by trophoblasts (enzymes digest endometrial tissue, carve hole in endometrium for implantation of blastocyst, release nutrients from endometrial cells for use by developing embryo)