Question

Which one of the following is categorised as a
parasite in true sense ?
(a) The female Anopheles bites and sucks
blood from humans
(b) Human foetus developing inside the uterus
draws nourishment from the mother
(c) Head louse living on the human scalp as
well as laying eggs on human hair
(d) The cuckoo (koel) lays its eggs in crow’s nest

Answer 1

Answer:

c

Explanation:

because louse take nutrition from human body but it doesn't give any benefit to human also couse disease in human.

Answer 2

Parasite in true sense is -

(c) Head louse living on the human scalp as well as laying eggs on human hair

Parasites are the organisms which live with host organism and benefit from them. Parasites feed on host for nutrients.

The cuckoo (koel) lays its eggs in crow’s nest is not an example of parasitism because the event occurs only during brooding phase.

Human foetus developing inside the uterus draws nourishment from the mother, here too, foetus is not dependent for lifetime but only for development period. Thus, case is not of parasitism.

The female Anopheles bites and sucks blood from humans for reproduction and nourishment of its eggs, not for feeding or its nutritional requirements.

Hence, this too is not the case of parasitism.