Lect 30 Flashcards
pregnancy can be divided into what 4 stages
- initiation
- gestation
- parturition
- lactation
site of fertilization
- oviduct
- normally occurs in upper third (ampulla)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/179/033/720/a_image_thumb.gif?1454699094)
fertilization must occur within what time frame after ovulation
24 hours
how does female reproductive tract aid in sperm migration
- contraction of myometrium
- upward contraction of oviduct smooth muscle
-
Allurin released by mature eggs
- chemoattractant for sperm to reach egg in ampulla of oviduct
upon sperm passage through female reproductive tract, process of what occurs
-
capacitation: or activation
- surface characteristics of sperm are altered
- cholesterol withdrawal
- surface prodteins redistributed
- calcium influx -> increase motility
- surface characteristics of sperm are altered
sperm motility in the cervical canal requires what pH? What makes this pH
- alkaline
- alkaline secretions from prostate gland
- estrogen makes mucus water
sperm transported is assisted by myometrial contractions. what is responsible for this
- prostaglandins in ejaculate
- estrogen-primed tissue
capacitated sperm penetrate the corona radiata, contact the zona pellucida and undergo what reaction
acrosome reaction
![](https://s3.amazonaws.com/brainscape-prod/system/cm/179/034/620/a_image_thumb.jpg?1454699864)
sperm contain receptors that bind to what protein that in turn triggers the acrosome reaction
ZP3 protein
what is the acrosomal reaction
- acrosomal enzymes digest zona pellucida creating a pathway to the plasma membrane of the ovum
![](https://s3.amazonaws.com/brainscape-prod/system/cm/179/034/722/a_image_thumb.jpg?1454700054)
sperm fusion to ovum’s membrane is mediated by
- binding of fertilin on sperm head to integrin receptor on ovum membrane -> zona reaction
What is the zona reaction
- release of cortical granules containing enzymes that degrade ZP3 proteins and harden zona pelucida
- prevent polyspermy
- signals ovum for completion of 2nd meiotic division
formation of female pronucleus and male pronucleus is termed
fusion
blastocyst is composed of what two cells
- trophoblasts cells: become placenta
- inner cell mass: become embryonic structure
![](https://s3.amazonaws.com/brainscape-prod/system/cm/179/035/049/a_image_thumb.png?1454700338)
blastocyst implants in endometrial lining by means of enzymes released by
trophoblast