Q.21 Ozone is a layer of atmosphere extending from ___________ km above earth and absorbs
ultraviolent radiations.
A) 10-50 C) 5-30
B) 50-60 D) 10-80
Q.22 Light rays from the sun are absorbed by CO2 and re-radiate as ________ radiations.
A) Ultraviolent C) Infra-Red
B) Indigo D) Green
Q.23 The gases which are produced by burning of fossils fuels and are responsible for acid rain are:
A) CFCs C) HCl and Oxides of Nitrogen
B) CO2 and CO D) SO2 and Oxides of Nitrogen
Q.24 During successions, the first organisms that develop on bare rock are:
A) Lichens C) Moss
B) Shrubs D) Herbs
Q.25 Trophic level of a herbivore in given food-web is:
Fox Owl Dog
Bettle Rat Rabbit
Grass
A) 1 C) 4
B) 3 D) 2