Placenta

Question 1

Hemochorial

Answer 1

Maternal and fetal blood does not mix

Question 2

Deciduate

Answer 2

Shed of

Question 3

Discoidal

Answer 3

Shape

Question 4

Placenta at term

Answer 4

500gm

Question 5

Placenta volume at term

Answer 5

500ml

Question 6

Ration of placenta : fetal wt at term

Answer 6

1:6

Question 7

Period of gestation when placental weight : fetal weight

Answer 7

17 weeks

Question 8

Functional unit of maternal placenta

Answer 8

Lobule aka cotyledon

Question 9

Placenta is attached to which side

Fetal or maternal

Answer 9

Fetal side

Question 10

Taltala surface area for gaseous exchange on maternal side is

Answer 10

12m square

Question 11

Stages of development Of villi

Answer 11

Primary -day 13 it is solid
Secondary - day 16 it is mesodermal core
Tertiary Villus - day 21 it contains vessels

Question 12

Maternal blood is present in which space 
Villus or intervillus
Amount of Blood present 
How many spiral arteries 
O2 saturation of intervillus space 
Partial pressure of O2 in IV space 
Rate of O2 delivery to foetus

Answer 12

Intervillus 
140ml 
120
65-75%
35-40mmHg
8 ml/kg/min

Question 13

When does placenta begins formation (anatomical)
Finishes formation (anatomical)
Physiologically it keeps maturing till

Answer 13

6 weeks

16 weeks 3rd trimester

Question 14

Which of the following is true for term placenta

1. No trophocytoblast
2. Syncitio blast increases
3. Stroma constant
4. Hoffbauer - fetal macrophages
5. Fetal capillaries decreases

Answer 14

1and 4 are correct
2,3,5 are wrong
2 - syncitioblast decreases (thin)-(thickness)
3 - stroma decreases
5 - fetal capillaries increase : they move towards periphery of villus

Question 15

Which of the functions of placenta is most imp

Answer 15

Endocrinology function

Question 16

Placental hormones

Answer 16

Estrogen
Progesterone
HpL
HCG

Question 17

What helps in maintaining of corpus luteum in Px

Answer 17

HCG

Question 18

Placenta takes over function of progesterone secretion at

Answer 18

8 weeks

8-10 weeks

Question 19

When does corpus luteum of pregnancy degenerates

Answer 19

12 weeks

Question 20

Precursor for progesterone synthesis

Answer 20

LDL cholesterol of mom

Question 21

Estrogen specific to pregnancy is

Answer 21

E3 (estriol)

Question 22

Which estrogen is produced in maximum amount at term

Answer 22

E2 (estradiol)

Question 23

Does placenta produce E by itself
If yes why?
If no why?

Answer 23

No placenta does not produce E by itself b/c it lacks 17 OH Lase
It takes help of foetus adrenal gland by secreting DHEAS (Dihydroepiandrosterone sulphate)- not cortisol and this makes placenta

Question 24

Names for HPL

Answer 24

Placental growth hormone (older days )
NOW
Human placental lactogen
Human chorionic somatomammotrophin

Question 25

Source of HPL/progesterone/estrogen/steroid

Answer 25

Syncitiotrophoblast

Question 26

HCS can be detected in how many weeks of gestation in maternal serum

Answer 26

3 weeks

Question 27

Production of HpL is maximum at what time

Answer 27

At term 1 gm per day Where as progesterone is only 250mg

Question 28

Hormone which tells about fetal well being

Answer 28

HCS

Question 29

Which hormone is responsible for fetal growth

Answer 29

Insulin/ insulin like growth factor

Question 30

Unique endocrinology function of HPL | Significance

Answer 30

Insulin resistance Insulin or insulin like growth factor is responsible for the fetal growth By making insulin resistance it avoids excessive growth of foetus

Question 31

T1/2 of HPL

Answer 31

30 days

Question 32

Which subunit is specific for HCG

Answer 32

Beta subunit

Question 33

Alpha and beta subunits of HCG closing resembles

Answer 33

Alpha - non specific for HCG resembles LH/FSH/TSH | Beta - specific for HCG closely resembles LH (differs by 8 A.A)

Question 34

HCG is secreted by which cells

Answer 34

Syncytiotrophoblast

Question 35

When can HCG be found in maternal serum

Answer 35

8th day post fertilisation

Question 36

T1/2 of HCG | Doubling time of HCG

Answer 36

24hrs (24-36 hrs) | 48hrs (1.4-2 days)

Question 37

``` Arrange in order of highest sensitivity test for HCG FIA (Fluoroscent immunoassay) IRMA ELISA RIA (radio immunoassay) RRA (radioreceptor assay) ```

Answer 37

FIA>RIA>ELISA=RRA>IRMA

Question 38

Critical titre value for TVS (transvaginal

Answer 38

1500 IU | Since TVS is operator dependant therefore range may vary from 1000-2000 IU HCG BETA

Question 39

Critical titre value for trans abdominal scan

Answer 39

6500 IU