Chapter 4 Prenatal Development & Birth
Reading Guide p97-103
1.) Where does the most dramatic and extensive transformation of the
entire life span occur? Before birth
2.) What are the first two weeks of prenatal development called?
Germinal period
3.) The 3rd through 8th week after conception is the embryonic period.
What develops during this time?
Neural tube, blood vessels, buds, arms & legs
4.) Fetal period is from week ___9th__ until birth.
5.) What MUST occur during this period?
Sex organs develop
6.) What percent of all natural conceptions fail to implant? In vitro?
60% natural 70% in vitro
7.) When can pregnancy be confirmed?
implantation
8.) How do obstetricians date the onset of pregnancy?
Last menstrual period
9.) What is LPM?
Last Menstural Period
10.)
Instead of germinal, embryonic, and fetal periods…most people
divide pregnancy how? trimesters
11.)
How is the due date determined?
LMP
12.)
If you are born “ on time” what does that mean?
3 weeks before or 2 weeks after
13.)
14.)
What system is the first to show any formal activity?
Nervous- neural tube (22 days)
What percent of all embryos are aborted spontaneously?
20%
15.)
What percent of all fetuses are aborted spontaneously before
viability?
5%
16.)
What determines the sex of an embryo?
If male (XY) gene on Y chromosome signals the
development of male sex organs
17.)
Explain what age of viability means?
Survive outside womb
18.)
Can fetuses hear by the age of viability?
yes
19.)
What was the world’s smallest surviving baby?
Rumasia
20.)
What were the 4 advantages she had?
1.) Her sex: female ( girls more likely to survive)
2.) Birthplace: Loyola Univ (specialize in low birth
weight babies),
3.) Birth process: Cesarean (easier on fetus)
4.) Reason for tiny size- twin (not malnutrition or
illness)
21.)
What is the critical difference between a fragile preterm baby
and a robust newborn?
Maturation of neurological, respiratory, and cardiovascular systems
22.)
Why is there such a substantial weight gain in the third
trimester?
Brain is developing….ensures developing brain is nourished