Human Reproduction — BIOLOGY STD 12 Science — Question

Name an opioid drug and its source plant. How does the drug affect the human body?

In general, the male gametes are motile while the female gametes are stationary. Mention two types of exceptions to this, with an example for each.

What is meant by the following:
Explant.

Name a free-living and a symbiotic bacterium that serve as bio-fertiliser. Why are they so called?

List any four parasitic adaptations in a parasite.
OR
List any four features evolved in animals to adapt to their parasitic mode of life.

Certain attributes of innate immunity are given in the table below. Identify A, B, C, D, E and Frespectively in it.

S.No.	Type of barrier	Example of the barrier	Function
(і)	А	B	Prevent microbial growth
(ii)	C	Polymorpho nuclear leucocytes	D
(iii)	Cytokine	E	F

Name the four levels of group organization of living things in order of increasing size.

Name the relationship between the first two words and suggest a suitable word
Doob grass : Runner : : Potato : ………

A man with blood group O and his wife with blood group AB claim a child with blood group AB as their son. With Punnett square justify their statement.

Sometimes even beneficial research turns out to be harmful, explain.