Section 4: Prenatal Development and Birth

Question 1

Periods of prenatal period:

Answer 1

Germinal
Embryonic
Fetal

Question 2

Germinal period is

Answer 2

begins when the mother’s and father’s germ cells are joined at conception, and lasts until the developing organisms becomes attached to the wall of the uterus, about 8-10 days later
includes cleavage and implantation

Question 3

cleavage is

Answer 3

zygote divides by mitosis into two cells, which then also divide, and so on

Question 4

heterochrony

Answer 4

different parts of the organism develop at different rates is called

Question 5

heterogeneity

Answer 5

variability in the levels of development of different parts of the organism at a given time

Question 6

totipotent stem cells are when

Answer 6

each cell has the potential to grow into an embryo, and, ultimately, a normal, healthy baby

Question 7

multipotent stem cells are when

Answer 7

the cell can become different types of cells, but not any type of cell

Question 8

Adult stem cells are ____ stem cells

Answer 8

multipotent

Question 9

Implantation is

Answer 9

process by which organism becomes attached to the uterus

a. Developing cell mass moves further into the uterus
b. Outer cells put out tiny branches that burrow into the spongy wall of the uterus until they come in contact with the mother’s blood vessels

Question 10

Embryonic period is

Answer 10

extends from the time the organism becomes attached to the uterus until the end of the 8th week

1. All the major organs take primitive shape
2. Organism begins to respond to direct stimulation
3. Period of rapid growth
4. Development of Placenta, Amnion, Amniotic fluid, and Chorion: Sources of Nutrition and Protection

Question 11

Amnion is

Answer 11

thin, tough transparent membrane that holds amniotic fluid

Early in development, surrounds the embryo

Question 12

Amniotic fluid is

Answer 12

1. Cushions the organism
2. Provides liquid support for its bones and muscles
3. Gives it a medium in which it can move and change position
   (In the amnion)

Question 13

Chorion is

Answer 13

membrane that surrounds the amnion

Later becomes the fetal component of the placenta

Question 14

Placenta is

Answer 14

complex organ made up of tissue from both the mother and the embryo

a. Barrier that prevents the bloodstreams of the mother and the infant from coming into direct contact
b. Filter that allows nutrients and oxygen to be exchanged
c. Converts nutrients carried by mother’s blood into food for the embryo
d. Enables the embryo’s waste products to be absorbed by the mother’s bloodstream

Question 15

The separation of inner cell mass into two layers occurs in what prenatal period?

Answer 15

Embryonic

Question 16

The ectoderm is

Answer 16

1. Outer layer
2. Gives rise to the outer surface of the skin, the nails, part of the teeth, the lens of the eye, the inner ear, and the nervous system

Question 17

The endoderm is

Answer 17

1. Inner layer

2. Develops into the digestive system and lungs

Question 18

The mesoderm is

Answer 18

1. Middle layer
2. Becomes the muscles, bones, circulatory system, and the inner layers of the skin
   Forms after ectoderm and endoderm

Question 19

Epigenesis is

Answer 19

idea that each new phenotypic form emerges as a result of the interactions that take place between the preceding form and its environment

Question 20

Two patterns of body development that are maintained until the organism reaches adolescence

Answer 20

i. Cephalocaudal pattern

ii. Proximodistal pattern

Question 21

Cephalocaudal pattern is when

Answer 21

development proceeds from the head down

Question 22

Proximodistal pattern is when

Answer 22

development proceeds from the middle of the orgnism out to the periphery

Question 23

No structural differentiation for first _____

Answer 23

six weeks

Question 24

gonadal ridge is

Answer 24

ridge of tissue from which the sex organs will develop

Question 25

Androgens are

Answer 25

1. Produced by male gonads

2. Male hormones, including testosterone

Question 26

Fetal period is

Answer 26

begins the 9th week after conception, with the first signs of the hardening of the bones, and continues until birth.

1. Primitive organ systems develop to the point where the baby can exist outside the mother without medical support
2. Ossification
3. Fetus increases in length and in weight dramatically
4. Organ systems increase in complexity

Question 27

Ossification is when

Answer 27

tissue that will become the skeleton begins to harden

Question 28

disease of spinal cord and backbone

Answer 28

Spina bifida

Question 29

disease of the brain and skull

Answer 29

Anencephaly

Question 30

Teratogens are

Answer 30

Environmental agents that increase risk of deviations in normal development and can lead to serious abnormalities or death

Question 31

In Stage 1 of labor

Answer 31

a. Uterine contractions of sufficient frequency, intensity, and duration begin to cause the cervix to dilate
b. Continues until the opening of the uterus into the vagina is fully dilated and the connections between the bones of the mother’s pelvis become more flexible

Question 32

In Stage 2 of labor

Answer 32

a. Begins as baby is pushed headfirst through the fully dilated cervix into the vagina
b. Contractions now no more than a minute apart and last about a minute
c. Pressure of the baby in the birth canal and the powerful contractions of the uterus cause the mother to bear down and push the baby out

Question 33

In Stage 3 of labor

Answer 33

a. Baby has emerged from the vagina
b. Uterus contracts around its diminished contents
c. Placenta buckles and separates from the uterine wall, pulling the other fetal membranes with it
d. Contractions quickly expel them, and they are delivered as the afterbirth

Question 34

used to rate babies’ physical condition at 1 minute and again at 5 minutes after birth using five vital signs

Answer 34

Apgar scale

Question 35

5 signs used in Apgar scale

Answer 35

i. heart rate
ii. respiratory effort
iii. Muscle tone
iv. Reflex responsivity
v. Color

Question 36

used to rate babies’ behavioral condition after birth

Answer 36

Brazelton Neo-natal Assessment scale

Question 37

5 signs used in Brazelton Neo-natal Assessment scale

Answer 37

i. Orientation to animate objects
ii. Pull-to-sit
iii. Cuddliness
iv. Defensive movements
v. Self-quieting activity