Developmental Flashcards
ovulation
14 days before next period
How many sperm reach Fallopian tubes
100, 50 reach egg. out of millions
How long are sperm viable
3-4 days
Fertilization
ovum turns into zygote. and implants in uterus
what percentage of zygotes survive
less than 50% survive
how long is gestation
38 weeks, 3 periods
blastocyst
fluid inside cell
Germinal stage
conception to implantation 5-8 days about 150 cells,
embryo
implantation 8 weeks, 56 days
rapid cell differentiation
placenta develops
how many weeks for survival is possible
20weeks -1lb, 26 weeks - 3-4lbs
end 8 weeks in embryo stage
heart beating, brain, spinal cord developing
Fetus stage
8 weeks to birth
organs functional
last 7 months: refining brain cells
reacts to light and sound
5 months
sex features
infant head proportions
head is 1/4 body
Bebinski
toes fan out