Fish breathe with the help of gills which are richly supplied with blood vessels. The gills help the fish to (a) take in oxygen from the air. (b) take in oxygen dissolved in water. (c) absorb nutrients present in water. (d) release waste substances in water.
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Soln:
The answer is (b) take in oxygen dissolved in water.
Explanation:
Fishes use gills for the exchange of gases. As the water enters through mouth it flows through gills. Capillaries in the gills absorb oxygen dissolved in water and also help in expelling out CO2 from the body.
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