Ch. 3 (part 2: Prenatal Development)

Question 1

name the three stages of prenatal development

Answer 1

germinal, embryonic and fetal

Question 2

BRIEFLY describe the germinal period (week # and two key events)

Answer 2

2 weeks, fertilization and implantation and start of placenta

Question 3

BRIEFLY describe the embryonic period (week # and one key event)

Answer 3

6 weeks, groundwork laid for all body structures and internal organs

Question 4

BRIEFLY describe the fetal period (week # and one key event)

Answer 4

30 weeks, “growth and finishing” phase

Question 5

list the three steps of implantation

Answer 5

zygote - blastocyst- implantation

Question 6

as the zygote moves down the fallopian tube …

Answer 6

it duplicates, at first slowly and then more rapidly

Question 7

describe what a blastocyst is

Answer 7

a zygote that on the fourth day forms a hollow fluid-filled ball

Question 8

(blastocyst) the inner cells, called the …, will become …

Answer 8

embryonic disk, the new organism

Question 9

(blastocyst) the outer cells, or …, will provide …

Answer 9

trophoblast, protective covering

Question 10

describe the stage of implantation

Answer 10

at the end of the first week, the blastocyst begins to implant in the uterine lining

Question 11

(the embryonic period)
upon implantation, this __-___ ______ is called an _____

Answer 11

multi-cellular organism, embryo

Question 12

when do blood vessels grow to form the placenta

Answer 12

during the embryonic period

Question 13

the placenta is a structure …

Answer 13

connected to the uterus that provides nourishment and oxygen from the mother to the developing embryo via the umbilical cord

Question 14

list the two directions of growth during prenatal development

Answer 14

cephalocaudal development and proximodistal development

Question 15

list three things that occur in the first trimester

Answer 15

organs, muscles and nervous system organize, lungs begin to expand and contract and sex of fetus is visible

Question 16

list three things that occur in the second trimester

Answer 16

active fetus; mother can feel movement, neurons rapidly form synapses, sensitivity to sound and light emerges

Question 17

neurogenesis (define) is largely completed after …

Answer 17

the formation of neurons, five months of gestation

Question 18

grey matter refers to the …

Answer 18

regions of the brain that contain cell bodies

Question 19

white matter consists of …

Answer 19

the axons that form neural pathways