Toni - Week 1 - Exam 1 Flashcards
What are the 4 functions of amniotic fluid?
Protection, Temperature Control, Fetal Growth, and Movement
T/F: Amniotic fluid volume is constantly changing
TRUE
How does the mother help create amniotic fluid?
Amniotic fluid is derived in part from maternal blood moving across the amnion
How does the fetus add and remove fluid volume?
Adds to amniotic fluid via urine
removes amniotic fluid by swallowing
How much does amniotic fluid increase at term?
Volume increases weekly to a LITER at term
What is oligohydramnios?
Too little fluid - could result from fetal kidney problems
What is polyhydramnios?
Too much fluid - could result from GI tract problems
What is the chorion?
the outer sac next to uterine wall
what is the amnion?
the INNER sac next to fetus. Thin & translucent, but high in tensile strength. originated from the blastocyte
What type of jelly is a characteristic of the umbilical cord and what is its function?
It is Wharton’s Jelly and it’s a thick substance that protects the vessels
How many vessels does the umbilical cord have?
3 vessels - 2 arteries and 1 vein (AVA)
- 2 arteries carry DE-OXYGENATED blood from fetus to placenta
- 1 vein carries OXYGENATED blood to the fetus
What is the average length of the cord at term?
22 inches
When the umbilical cord is cut, can the mother /fetus feel pain?
No, it lacks sensory neurons. Good to reassure fathers/partners that this will not hurt.
Where does the placenta develop and what size is it at term?
Placenta develops at the site of embryonic attachment; it’s 1/6 the size of newborn - placenta develops the size of the newborn.
What are the 4 functions of the placenta?
fetal gas exchange, nutrition, excretion, and hormone regulation
What is the placenta composed of?
maternal and fetal tissues
The layers of fetal tissues form a placental barrier, what is the purpose of this barrier?
- Materials only exchanged via diffusion
- Prevents contact between fetal and maternal blood
What are the two different surfaces of the placenta?
- maternal surface (red/uneven) attaches to uterine wall
- outer fetal surface (gray/shiny) contains umbilical vessels and cord
What is the most crucial stage of development?
the embryonic stage
What is the “all or nothing” period?
Period between ovulation and implantation
Not yet sustained by mother; sustained by corpus luteum
No teratogens effect
Will die or live with no consequence
How much blood needs to go to the liver and lungs of a developing fetus?
Just enough to nourish the tissues
What are the 3 fetal shunts?
Foramen Ovale, Ductus Venosus, and Ductus Arteriosus
What is the Foramen Ovale?
A flap in the wall between the right and left atrium of the heart that allows a large percentage of oxygenated blood to go out into the body (blood goes from RA to LA and out into the body)
- will functionally close at birth with the change in pressure gradient that will occur with normal circulation
What is the Ductus Arteriosus?
A tiny, little shunt that connects the pulmonary artery and the aorta - some that is unnecessary in the lungs/pulmonary artery carries over to the aorta.
- will functionally close at birth d/t change in pressure gradient