Reproductive cont. Flashcards
- Pre-embryonic development
fertilization through second week
2 Embryonic development
wk 3 - wk 8
- Fetal development
wk 9 - birth
development after birth
postnatal
main processes of development
- cleavage
- growth
- morphogenesis
- differentiation
cleavage
cell mitotic division (2, 4, 8..) w/o embryo increasing in size
growth
cell mitotic division + size increase
morphogenesis
embryo begins to take shape as cells migrate
- “morpho” shape
- “genesis” beginning
differentiation
cells take on specific structure and function (nervous system = first visible system of embryo)
fertilization steps 1
secretions from female reproductive tract alter surface of plasma membrane of sperm
fertilization steps 2
sperm contacts corona radiata, and enzyme; spill out of acrosome
fertilization steps 3
enzymes disrupt cellular attachments (allowing passage of sperm through corona radiata -> zona pellucida
fertilization steps 4
sperm contacts plasma membrane of secondary oocyte -> plasma membranes fuse
fertilization steps 5
sperm enters cytoplasm of secondary oocyte
fertilization steps 6
granules near plasma membrane of secondary oocyte release enzymes -> zona pellucida hardens
fertilization steps 7
nucleus of sperm and egg fuse (fertilization completed)
pre-embryonic development wk 1 step 1: ovulation
secondary oocyte released from ovary and swept into eviduct
pre-embryonic development wk 1 step 2: fertilization
single sperm penetrates secondary oocyte -> sperm and egg nuclei fuse -> zygote
pre-embryonic development wk 1 step 3: cleavage
mitotic division w/o size increase
pre-embryonic development wk 1 step 4: morula
solid ball of cells that enters uterus
pre-embryonic development wk 1 step 5: blastocyst
hollow ball of cells w/ fluid-filled cavity
- increases in size
pre-embryonic development wk 1 step 6: implantation
blastocyst attaches to endometrium -> cells of inner cell mass form primary germ layers
chorion
fetal half of placenta
- organ nourishes embryo and gets rid of wastes by exchange w/ mother’s blood
allantois
gives rise to bladder and blood vessels of umbilical cord that carry blood to-fro fetus
yolk sack
contains many blood vessels and where blood cells first form
- primordial germ cells
amnion
contains amniotic fluid for protection/cushioning
embryonic development wk 2
- pregnancy begins after implantation
- human chorionic gonadotropin (HCG) secreted (maintaining corpus luteum and endometrium
- embryonic disk goes through gastrulation
gastrula
embryo w/ ectoderm, mesoderm, endoderm
ectoderm (outer layer)
skin epiderms, epithelial lining cavity and rectum, nervous system
mesoderm (middle)
skeleton, muscular, cardiovascular, urinary, reproductive, outer layers of respiratory/digestive
endoderm (inner)
epithelial lining of digestive and respiratory tract,
embryonic development wk 3
- nervous system develops
- neural tube -> spinal cord and brain
- development of heart begins
embryonic development wk 4
- chorionic villi and umbilical cord forms
- heart beats
- limb buds form
- hands/feet
embryonic development wk 5
- head enlarges
- eyes, ears, nose
fetal development months 3/4
- hair development
- head slows in growth
- cartilage -> bone
- female/male
- heartbeat
fetal development months 5-7
- fetal movement
- fetal position
- eyelids fully open
- growth
fetal development months 8/9
- gains a pound/week
- fetus rotate (head pointed towards cervix)
anti-mullerian hormone
secreted by testes, prevents development of female sex organs
dihydrotestosterone (DHT)
external organ development dependent of presence/absence of this (produced by testes)
bad changes in mother’s body
- effect of progesterone (acid reflux, constipation)
- morning sickness
- edema and varicose veins
- gestational diabetes
- stretch marks
birth stage 1 (dilation)
regular contractions, ends when cervix is dilated 10 cm
birth stage 2 (expulsion)
begins w full dilation of cervix and ends w/delivery of baby
birth stage 3 (placental)
ends w/expulsion of placenta
