Pick the odd-one-out from each of the groups given below on the basis of respiratory organs. Give a reason for your answer. (a) cockroach, grasshopper, snail, ant (b) lizard, cow, earthworm, snake (c) crocodile, whale, dolphin, fish (d) snake, tadpole, crow, goat
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Soln:
a) Snail- Because snail does not breathe by trachea, whereas cockroach, grasshopper and ants breathe by the trachea
b) Earthworm-because it breathes through its skin and it does not have lungs.
c) Fish- because fish don’t have lungs and they breathe by their gills.
d) Tadpoles- because tadpoles don’t have lungs and they breathe by their gills.
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