Placentation

Question 1

What are the classification of placenta?

Answer 1

1. Contact of blood vessels with the uterus 2. Type implantation 3. Number of maternal layers

Question 2

Enumerate the contact of blood vessels with the uterus:

Answer 2

1. Diffuse 2. Cotyledonary 3. Zonary 4. Discoid

Question 3

The point of contact is scattered all throughout and what animals are under it?

Answer 3

Diffuse (sows and mares)

Question 4

The point of contact is confined in a button like structure & what animal is under it?

Answer 4

Cotyledonary ( ruminants like cattle, sheep, goats)

Question 5

The point of contact is scattered but belted and what animal is under it?

Answer 5

Zonary ( carnivores: dogs & cats)

Question 6

Humans have this at later stage 1. And what do they have at early stage? Live examples.

Answer 6

1. Discoid 2. Diffuse ( primates & rodents)

Question 7

The placenta is centrally located and what animals are under it?

Answer 7

Central (carnivores, monkeys, ungulates)

Question 8

Located only at one side of uterus and what animal are under it?

Answer 8

Eccentric ( rodents)

Question 9

Also at one side but no side of contact. Give example.

Answer 9

Interstitial ( humans, guinea pig, some rodents at early stages

Question 10

Has a complete 3 layers what animals are under it?

Answer 10

Epitheliochorial (mares & sows)

Question 11

Disappearance of uterine epithelium and what Iayer stays? Give example.

Answer 11

Endotheliochorial ( connective tissues and endothelium) (cats and dogs)

Question 12

Disappearance of uterine epithelium and endothelium lining • what layer is left? Give example.

Answer 12

Hemochorial ( connective tissue) (humans & rodents)

Question 13

All maternal layers are missing and maternal blood circulation has direct contact. What animalis under them?

Answer 13

Syndesmochorial (ruminants)