1- Fish breathe ............ gas dissolved in water.

2-……………. destroy the lungs and causes many diseases.

3- The main control center in body..............

4- Echolocation helps dolphin identify...........

Put (√) or (×).

1- Burning forests is one of the positive human activities on the environment. ( )

2- The ecosystem can be restored by eliminating pollution. ( )

3- The body of amphibians is covered with a skin that allows water and gas to pass through. ( )

4- The Egyptian frog lives in ponds and streams. ( )

5- Dolphins have  strong sense of hearing than human do.  (   )