Organs for breathing

Not all animals have the same organs fo r breathing. Microscopic organisms, such as Paramecium and Amoeba, breathe through their body surface. Insects breathe through small openings, known as spiracles, present on the thorax and abdomen of their bodies. Spiracles are connected to the trachea*.

Animals, such as earthworms, breathe through their thin and moist skin. Some aquatic animals, such as fishes, prawns and oysters, breathe through their gills. Amphibians, such as frogs, breathe through both their gills and lungs. A tadpole breathes through gills, whereas an adult frog breathes through lungs on land and through its moist skin in water.

HOW ANIMALS MOVE?

Different animals have different body parts that help them move from one place to another.

Land animals

Almost all mammals have fo ur limbs. The two limbs that are present at the front are called forelimbs and the two at the back are called hindlimbs.

Aquatic animals

Fishes have fins that enable them to swim. Turtles have four paddle-like limbs that help push water in the backward direction. Frogs use their webbed feet to swim and long hindlegs to jump on land.

Insects

Some insects, such as cockroaches and ants, crawl on their legs. Water insects use their legs to swim. Some insects, such as flies, beetles and wasps, have wings that help them fly.

Birds

The forelimbs of birds are adapted into wings. Wings help them fly. These wings have feathers and are joined to the breastbone of birds through strong muscles. The hindlimbs of birds are used for walking, hopping, perching and running. Birds which cannot fly are known as flightless birds. Such birds depend on their ability to run or swim for their moveme nt. Ostriches, penguins and emu are a few flightless birds.