Lungs are the part of some animals like pigs that helps them breathe air. Gills are the part of fish that takes air from the water to help them breathe. This document discusses and compares the organs that different types of animals use to breathe - lungs for air-breathing animals and gills for fish.

3. The part of some animals that helps them breathe
air. Pigs are animals that breathe using lungs.

4. The part of a fish that takes air from the
water.