Multiple choice

In sponges, the exchange of gases occurs through

  1. Gills

  2. Lungs

  3. Cellular surface

  4. Trachea

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In simple multicellular animals, such as, sponges, cnidarians, etc., each cell of the body remains in contact with the environment (water) and thus, exchange of gases takes place through the surface of the cell by diffusion.