Chapter 2: Prenatal development and newborn period

Question 1

epigenesis

Answer 1

Aristotle; the emergence of new structures and functions during development

Question 2

Gametes

Answer 2

sperm and egg; produced through meiosis (special type of division with egg and sperm to receive only one of 23 chromosome pairs)

Question 3

conception

Answer 3

if sexual intercourse takes place near the time the egg is released
1 ejaculation can have 500 million sperm, must travel 6 hours (6 to 7 inches), only 200 get near egg (the healthiest, Darwin’s survival of the fittest)

Question 4

periods of prenatal dev

Answer 4

conception to 2 weeks:
-germinal
-conception, zygote implants in uterine wall, rapid cell division
3rd to 8th week:
-embryonic
-cell division, migration, differentiation, and death and hormonal influences
9th week to birth
-fetal
-continued dev of physical structures, rapid growth, and increasing behavior, sensory levels, learning

Question 5

cel migration

Answer 5

movement of newly formed cells away from point of origin

Question 6

cell differentiation

Answer 6

embryonic stem cells start to specialize in structure/function (expressed or “switched on” genes)

Question 7

phylogenetic continuity

Answer 7

because of common evolutionary history, humans share many characteristics and dev processes with other living things

Question 8

apoptosis

Answer 8

selective cell death preprogrammed so that cells will disappear

Question 9

3 layers of embryonic dev (2nd week)

Answer 9

top layer: nervous system, nails, teeth, inner ear, lens of eye, outer layer of skin
middle layer: muscles, bones, circulatory system, inner layers of skin, other internal organs
bottom layer: