Whales and dolphins keep coming to the surface of water to breathe in air.
True
False
We must always let water stagnate in and around our house.
We put a spoonful of sugar in the tanks of water coolers to prevent mosquitoes from laying eggs.
Free-floating plants have spongy and air-filled parts.
Lotus and water lily have a long and hollow stem.
Which of the following organs do fish and crabs use to breathe in air?
Lungs
Gills
Skin
Which of the following animals have webbed feet that help them to wade through water?
Lobsters
Dolphins
Ducks
Which of the following aquatic animals have a streamlined body?
Crabs
Turtles
Fish
What do aquatic weeds cause?
Water pollution
Malaria
Typhoid
Bulrush
Lotus
urine
blood
insects
birds
free-floating
rooted-floating
