Human Health and Disease — BIOLOGY STD 12 Science — Question

Given below is a list of autotrophs and heterotrophs. With your knowledge about food chain, establish various linkages between the organisms on the principle of ‘eating and being eaten’. What is this inter-linkage established known as?
Algae, hydrilla, grasshopper, rat, squirrel, crow, maize plant, deer, rabbit, lizard, wolf, snake, peacock, phytoplankton, crustaceans, whale, tiger, lion, sparrow, duck, crane, cockroach, spider, toad, fish, leopard, elephant, goat, Nymphaea, Spirogyra.

Identify a, b, c, d, e and f in the table given below:

	Organism	Bioactive molecule	Use
1. 2. 3.	Monascus perpureus (yeast) c e	a d Cyclosporin A	b antibiotic f

Match Column I with Column II.

S. No.	Column I	S. No.	Column II
A.	Cleavage	1.	Outer layer of the blastocyst that attaches to the endometrium during implantation.
B.	Implantation	2.	Mitotic divisions of the zygote in quick succession.
C.	Inner cell mass	3.	Embedding of the blastocyst in the endometrium of uterus.
D.	Trophoblast	4.	Release of secondary oocyte from the ovary.
E.		5.	Group of cells attached to one end of trophoblast that differentiate into embryo proper.

Why is hormone releasing IUD considered a good contraceptive to space children?

Differentiate between homology and analogy. Give one example of each.

Name the regions marked A, B and C.

'Predation is beneficial in long run'. Comment.

What is the role of histamine in inflammatory response? Name few drugs which reduce the symptoms of allergy.

Draw a labelled diagram of a Graafian follicle?