FETAL SUPPORT STRUCTURES, STAGES OF INTRAUTERINE DEVELOPMENT AND FETAL CIRCULATION Flashcards
T or F = The study of development begins at birth
false, it begins at the moment of conception
What is decidua?
inner lining of uterus implanted with blastocyst
Structure of thickened endometrium that develops after implantation
What are the 3 decidua layers
1 Decidua Basalis
2 Decidua Capsularis
3 Decidua vera
Decidua Basalis location and function
L: Lies directly under embryo
F: Where trophoblast cell communicates w/ maternal blood vessels
Decidua Capsularis location and function
L: Encloses the embedded blastocyst
F: Separates blastocyst from uterine cavity
Decidua Vera location and function
L: Layer not in contact w/ ovum
F: Lines the remaining uterus
The decidua layer that becomes the maternal part of the placenta
decidua basalis
are called finger-like projections
Chorionic Villi
Contains a reservoirs of blood which provides O2 and Nutrients to fetus
intervillous spaces
Tiny Projections into the intervillous space that contain a fetal artery and vein to release waste products & pick up oxygen & nutrients from maternal blood
Chorionic Villi
fetal membranes is also known as
embryonic membrane
Function of fetal membrane
encloses fetus & amniotic fluid, protecting it from bacterial infection
2 Division of fetal membrane
Chorion (chorionic membrane) & amnion (amniotic membrane)
The outer most fetal membrane and is described as protective & nutritive
Chorion
Smooth, glistening, thin, tough, & translucent fetal membrane that lines the amniotic cavity, enclosing the fetus
Amnion
Produces the amniotic fluid
Amnion
Described as bag of water as it contains the amniotic fluid
amniotic cavity
the fetus’ position withing the amniotic cavity
flexion
The amount of amniotic fluid in mL ranges from
800-1200 mL
what is the color, alkalinity, and composition of amniotic fluid
color: clear
alkalinity: 7-&.25
composition: 99% water & 1 % solid particles
amniotic fluid function (8)
- Protection
- Allows movement
- Permits symmetrical growth
- Excretion
- Fetus has fetal waste metabolism, so it urinates & urine goes to circulation
- Temperature regulation
- Source of intrauterine oral fluid
- Lubricant during labor
To determine if the amniotic fluid or urine is the one that raptures and come out (during the time when it is thought that pregnant woman is about to deliver), what test is utilized?
Nitrazine Paper Test
Test that involves putting a drop of fluid sample from vagina onto litmus paper strips with nitrazine dye.
Nitrazine Paper Test
Yellow result of Nitrazine Paper Test indicates?
pH is 4-6
Negative for amniotic fluid
