Question

On what basis are mammals classified into different groups, and what these groups?

Answer 1

• Monotremes
• Marsupials
• Placental

Explanation:

• Monotremes

Monotremes are the mammal who lay eggs.
Eg: *Duck-billed Platypus, Echidna.*

• Marsupials

Marsupials Give birth to undernourished babies.

They doesnt have a placenta .
They keep their babies inside a pouch attached with their stomach where the baby is well-nourished.
Eg: Kangaroo.***

• Placental
  Placental mammals consist of the rest of the mammals who nourish their babies in placenta, in the early stage of the babies.
  Eg: *Humans, Dogs, Cats.*

Placenta - is a organ or a* lining which enables transportation of Nutrients from mother's body to the baby via Umbli cord.
[ It further injects the faecal matter produced by the baby into mother's blood.]