Prenatal Development

Question 1

What are the 3 periods of prenatal development

Answer 1

1. Germinal/Zygotic period
2. Embryonic period
3. Fetal period

Question 2

Timeframe and qualia of the Embryonic period

Answer 2

3rd-8th week, 3 main cell layers from rapidly

1. Ectoderm - develops into the nervous system, skin and hair
2. Mesoderm - develops into the muscles, bones and circulatory system
3. Endoderm - develops into the digestive system, lungs, urinary tract and other vital organs.

Question 3

6 Factors of the embryonic period

Answer 3

1. ears are formed
2. Eyes develop cornea, lenses
3. rudimentary skeleton formed
4. Limbs develop
5. Brains develop rapidly
6. around 2.5 cm, 7grams

Question 4

4 factors of the 3rd month (beginning of the fetal period)

Answer 4

1. Able to kick, twist - not felt by the mother
2. Can swallow, digest and urinate
3. Testosterone is secreted by testes of the males, the absence of which develops female genitals
4. 7.5 cm long and under 28 gs

Question 5

4 factors of the second trimester

Answer 5

1. more refined motor and sensory actions
2. Kicking felt by mother
3. Heartbeat can be heard using a stethoscope
4. eyebrows, eyelashes and scalp hair appear

Question 6

What are the 3 compounds covering fetus’s

Answer 6

1. Amniotic fluid
2. Vernix (white cheesy covering to prevent chapped skin)
3. Lanugo (fine layer of body hair)

Question 7

Characteristics of the third trimester

Answer 7

Organ systems mature
Weight gain
enters the Age of Viability (22-28 weeks, can potentially survive independent of the mother)
Moves into a head-down position in 9th month
48-53 cm, 3.2 - 3.6 kg

Question 8

Can the fetus respond to sound? taste? detect temperature? see?

Answer 8

Sound - yes, 2nd trim, reacts to mothers speech (measured by monitoring mvmt)
Taste - yes young as 12 w, discriminates between sweet and noxious compounds added to the amniotic fluids
Temp - anecdotally, yes, although the amniotic fluid remains at such a regular temperature that there is little to no method of testing
sight - yes, eyes open around 28 weeks (vision is the last system to develop, will react to bright lights on moms stomach, not a fully developed sense like ours.)

Question 9

What are the 3 Principles that guide development?

Answer 9

1. Dev. proceeds in a cephalocaudal direction (head to toe/extremities)
2. Dev. proceeds from basic to more specialized (ie heart begins w 2 chambers, then expands to 4)
3. Dev. proceeds in order of importance (brain and heart 1st organs to dev.)

Question 10

What is the APGAR test? How is it conducted?

Answer 10

A - Appearance: colour 
P - Pulse: heartrate 
G - grimace: reflex irritability 
A - Activity: Muscle tone and movement
R - Respiration - breathing
-conducted at 1, 5 mins after birth, with a score of 7 or higher being good, lower than 4 requires medical attention.