Question:
What is placenta ? Mention its role during pregnancy. (CCE 2011, 2014)
Solution:
Placenta: It is a special double layered, spongy tissue connection between the foetus and uternine wall found in pregnant females. It has finger-like outgrowths or villi which are in contact with blood sinuses present in the uterine wall.
Role:
- Attachment: Placenta attaches the foetus to uterine wall.
- Villi: Placenta has finger-like outgrowths or villi which develop a large surface area for fixation and absorption.
- Nutrients: Placenta picks up nutrients from mother’s blood and passes it to the blood of the foetus.
- Waste Products: Waste products produced by the foetus passes out through the placenta into mother’s blood.
- Gases: Foetus obtains oxygen supply from mother’s blood and eliminates carbon dioxide through placenta.