Fetal Development & Delivery

Question 1

3 layers of embryo

Answer 1

1. ectoderm
2. mesoderm
3. endoderm

Question 2

supportive structures for fetal development (3)

Answer 2

1. amnion
2. placenta
3. umbilical cord

Question 3

amnion

Answer 3

sac filled with fluid that cushions and protects fetus

Question 4

placenta

Answer 4

temporary organ

carries out all nutritive, respiratory, excretory, endocrine functions of embryo/fetus

Question 5

umbilical cord

Answer 5

connects embryo/fetus to placenta

Question 6

ectoderm becomes (2)

Answer 6

skin + nervous tissue

Question 7

endoderm becomes (4)

Answer 7

• glands
• liver
• pancreas
• lining of hollow organs (resp/dig system)

Question 8

mesoderm becomes

Answer 8

everything else (cardiovascular system, muscle, rbcs, etc)

Question 9

important milestones of first trimester (5)

Answer 9

• heart starts beating
• head shape formed (disproportionately large)
• neurulation
• arms/legs begin forming, movable joints develop
• eyes/ears/nose form (incorrect positions)

Question 10

heart beat timeline

Answer 10

• starts at wk 3

- can be heard via ultrasound by week 6

Question 11

when embryo becomes fetus

Answer 11

week 8

Question 12

when moveable joints develop

Answer 12

by week 13

Question 13

important milestones of second trimester (6)

Answer 13

• head + body grow to proper proportions (things in the right place)
• unique fingerprints develop
• lanugo grows
• mother can feel movement
• fetus has sleep/wake cycles
• heart gets regular rhythm

Question 14

when eyes can detect light and dark

Answer 14

by week 16

Question 15

lanugo

Answer 15

fetal hair that grows to keep fetus warm

Question 16

when start to feel movement

Answer 16

by weeks 18-21

Question 17

neurulation

Answer 17

formation of neural tube from outer folds of ectoderm

Question 18

neural tube becomes (2)

Answer 18

• anterior –> brain

- rest –> spinal cord + brainstem

Question 19

neurulation steps (3)

Answer 19

1. lateral sides of the ectoderm move together (convergence) –> form the epidermis superficially
2. neural fold forms underneath the epidermis –> becomes neural crest.
3. neural plate –> neural groove –> neural tube once convergence is complete

Question 20

important milestones of third trimester (6)

Answer 20

• systems in place continue developing
• weight increases + fat develops under skin
• lungs mature
• able to self regulate temperature
• sucking reflexes
• testes (if present) descend into scrotum

Question 21

general size of fetus at full term

Answer 21

• 19-22 inches

- 6-10 lbs

Question 22

oxytocin

Answer 22

stimulates myometrium to contract