L6: placenta & fetal membranes

Question 1

What is the Functions of the fetal membrane?

Answer 1

Protection

Question 2

What do the Fetal membranes include?

Answer 2

• Amnion
• Chorion > sheet membrane of extraembryonic origin to support the fetus
• Yolk sac
• Allantois > ( connective stalk - came from extraembryonic mesoderm)

Question 3

From where do it develop? (the fetal membrane)

Answer 3

These develop from the zygote

Question 4

What is the importance of the amnion and chorion?

Answer 4

• essential for fetal development

- Transfer of nutrients during 2nd and 3rd weeks of development

Question 5

The amnion and chorion do not participate in…

Answer 5

the formation of the embryo or fetus > bc they are derived from the extraembryonic mesoderm

Question 6

The yolk sac is incorporate as

Answer 6

primordium of the gut

Question 7

When does Blood cells develop?

Answer 7

Blood cells develop in its wall from 3rd to 6th week of development

Question 8

When does the Primordial germ cells appear in its wall?

Answer 8

in the 3rd week of development

Question 9

What is the importance of the Allantois?

Answer 9

• forms urachus in the fetus
• and median umbilical ligament in the adult Blood cells develop in its wall from 3rd to 5th week
• Its blood vessels persist as the umbilical vein and arteries

Question 10

What is the Functions of the placents?

Answer 10

Metabolism

Production of hormones

Question 11

metabolism of placenta synthesizes what

Answer 11

Synthesis of glycogen, cholesterol, and fatty acids > provides nutrition

Question 12

passive immunity from the mother to the fetus

Answer 12

Maternal immunoglobulin G

Question 13

what are the hormones produced by placenta?

Answer 13

o Human chorionic gonadotrophin HCG
o Progesterone
o Estriol
o Somatomammotropin

Question 14

abnormal secretion of Somatomammotropin leads to…..

Answer 14

pregnancy diabetes

Question 15

When does the Placenta start to develop?

Answer 15

As soon as implantation > syncytiotrophoblast start invading the endometrium

Question 16

What is the Placenta?

Answer 16

is a fetomaternal organ > fatal components and mother component

Question 17

where does the fetal part develops from

Answer 17

from the chorionic sac

Question 18

where does the maternal part derived from

Answer 18

the endometrium > blood source

Question 19

hemochorial Type

Answer 19

no mixing in the blood (placenta)

Question 20

Where does the Implantation of a blastocyst take place?

Answer 20

The endometrium of the uterus

Question 21

what is the decidua?

Answer 21

• the functional layer of the endometrium in a pregnant woman
• which separates from the remainder of the uterus after childbirth > shut off after birth

Question 22

How many regions of the decidua are there?

Answer 22

The three regions

Question 23

decidua are named according to

Answer 23

their relation to the implantation site

Question 24

what are the 3 regions of decidua?

Answer 24

• basalis
• capsularis
• parietalis

Question 25

The decidua basalis

Answer 25

forms the maternal part of the placenta.

Question 26

The decidua capsularis

Answer 26

overlies the conceptus.

Question 27

decidua parietalis

Answer 27

is all the remaining parts of the decidua

Question 28

what is the chorionic plate?

Answer 28

it is a layer of the extraembryonic mesoderm that marks the fetal part of the placenta

Question 29

Amnion

Answer 29

sac that the baby will swim in

Question 30

how many arteries & veins does the umbilical cord have

Answer 30

* 2 arteries > deoxygenated blood | * one vein > oxygenated blood

Question 31

Describe the mother blood circulation?

Answer 31

* Arteries >oxygenated | * Vein > deoxygenated

Question 32

why do we need to maintain villi

Answer 32

to allow blood to flow | between the spaces for gas exchange

Question 33

What happens to the barrier from week 4 to the 4th month?

Answer 33

The barrier decreases end becomes thinner In order to ease the exchange

Question 34

why does the villi changes their morphology?

Answer 34

to increase | the blood exchange due to the growth of the fetus

Question 35

How many cotyledons Maternal side exhibit?

Answer 35

Maternal side exhibits 15-20 cotyledons separated by | decidual septa

Question 36

what is decidual septa

Answer 36

These are spaces between the villi

Question 37

What coveres the Fetal surface?

Answer 37

the chorionic plate, which is covered by the amnion.

Question 38

What are the products that are carried away from the fetus by the umbilical arterys?

Answer 38

Waste products o carbon dioxide, water, urea, uric acid ,Bilirubin Other substances o RBCs antigen o hormones

Question 39

What are the products that are brought to the fetus via the umbilical vein?

Answer 39

- Oxygen and nutrients | - Harmful substances

Question 40

Non-transferable substances

Answer 40

cant pass (ex: bacteria,heparin,transferrin IgS &IgM)`

Question 41

The waste product will be disposed by

Answer 41

the umbilical circulation

Question 42

Describe a Monozygotic twins ?

Answer 42

They come from one oocyte > but during the cleavage two embryoblast are formed

Question 43

Monozygotic twins have

Answer 43

o One placenta o One chorionic sac o Two amniotic sacs

Question 44

Describe a dizygotic twins?

Answer 44

Two different oocytes

Question 45

dizygotic twins could be due to

Answer 45

- continuous AMH hormone secretion | - Or because both ovaries ovulated and released eggs at the same time

Question 46

dizygotic twins have

Answer 46

* One placenta or two * Two chorionic sac * Two amniotic sacs

Question 47

What are the presenter abnormalities ?

Answer 47

Placenta accreta: Placenta percreta: Placenta previa:

Question 48

Placenta accreta:

Answer 48

is when the chronic villi goes deep goes into the myometrium

Question 49

Placenta percreta:

Answer 49

is when the chromic villi goes through the myometrium and attaches to the perimetrium the only treatment is the removal of the uterus

Question 50

Placenta previa:

Answer 50

is attaches of the embryo in the lower segment of the uterus > Interior OS of the uterus > needs cesarean section.

Question 51

What are the Significance of amniotic fluid?

Answer 51

* Permits symmetrical growth of the embryo and fetus * Acts as a barrier to infection • Prevents adherence of amnion to the embryo and fetus * Permits normal fetal lung development * Cushions the embryo and fetus * Enables movement of the fetus aiding in muscular development * Maintains homeostasis of fluid and electrolytes

Question 52

Oligohydramnios?

Answer 52

Refers to when there is a shortage of aminiotic fluid, it can cause the baby to be born with severe abnormalities including underdeveloped lungs and kidney agenesis

Question 53

Polyhydramnios?

Answer 53

• Refers to when there is an excess of aminiotic fluid, it can cause the baby to be born with severe abnormalities including anencephaly and esophageal atresia