Flashcards in Ch 10 - Conception & Fetal Dev Deck (100)
Union between a single sperm and egg that marks the start of a pregnancy
process of conception
Process by which oocytes and spermatocytes are produced
When does oogenesis begin?
When does spermatogenesis begin?
oogenesis: during fetal life. When a female is born, she is born with all the eggs she will ever have (2 million, most of which degenerate, leaving only 400-500)
spermatogenesis: starting from puberty, continues into 80s and 90s.
- what occurs
- hormones responsible for follicular rupture
- what occurs to make fraternal twins possible
Each month one ova matures and is released from its ruptured ovarian follicle
hormones responsible: LH, FSH. Occasionally, two ovum
are released, making fraternal twins possible
High levels of ________ increase the motility of the fallopian tubes so that the cilia are able to move the ova through the tube toward the uterus
Most common site of conception
If fertilization is to occur, it usually takes place in the _______ _______ of the tube
Ova are fertile for __ hours after ovulation. If fertilization does not take place in this timeframe, the ova breaks down and is reabsorbed.
Protective layers will need to be penetrated by sperm in order for fertilization to occur. This is able to occur when __________ from the ______ are released and aid in breaking down that protective coating of the ova
Typical male ejaculation contains # - # million sperm & can live in a woman’s reproductive tract for # - # days
2-5 million sperm
Occurs when a sperm is able to penetrate the membrane surrounding the ova
At this time, both ova and sperm become enclosed in the membrane
Progression of zygote to implantation
zygote --> 2 cell --> 4 cell --> morula (little mulberry) --> blastycyst/trophoblast/embryoblast --> implantation
eventually will be placenta
eventually will become embryo
whole structure of developing embryo
When the protective coating degenerates, trophoblast cells will displace the endometrial cells at the implantation site and the blastocyst embeds itself on the endometrium when uterus is at its most nourished
usually occurs in fundus endometrium w/in 6-10 days after conception
implantation in cervix
blocks baby's passage
What will secrete enzymes to allow the fertilized egg to burrow into the endometrium and cover the blastocyst?
What occurs @ the site of implantation that makes implantation bleeding occur? - usually around the same time as the when a period might occur which makes women miss the first month of pregnancy
Endometrial blood vessels erode
conception - day 14
week 2 - 8
Week 9 - birth
which period is the baby at greatest risk due to drugs, alcohol, trauma, malnutrition, smoking, lack of folic acid, measles?
what might these things cause?
Why is she @ greatest risk?
spontaneous miscarriage or fetal development issues
mom doesn't know she's pregnant
When do people generally realize they're pregnant?
What is the primary reason for barrier methods with pregnant women?
protection from STI
Develops into epidermis, glands, hair and nails, nervous systems, lens of the eye, tooth enamel, and floor of amniotic cavity
Develops into bones, teeth, muscles, dermis, connective tissue, spleen, genitourinary, and cardiovascular system
Lining of respiratory and digestive tracts, and the glandular cells of associated organs. Forms the roof of yolk sac.