Page 19 - Future Stars Science Explorer-5

folded back. The teeth present in the upper jaw are not meant for biting or
chewing but to hold back the prey. Lizards have a protrusible tongue. It is
thrown out with great force to catch insects. Mammals have different kinds of

teeth which enable them to catch their prey. They also use their forelimbs to
catch the prey.

Breathing Methods

We know that all animals need air to breathe. They take in oxygen and give

out carbon dioxide. Different animals have different organs for breathing.

Birds, reptiles, and mammals breathe through

their lungs. Air enters the body through the Nostrils
nostrils and reaches the lungs through a tube Wind pipe

called the wind pipe. The lungs take in oxygen
from the air. The lungs also pass out carbon Lungs

dioxide, which goes out of the body through Human beings breathe
the nostrils. through lungs

Spiracles Insects have small holes called spiracles on their bodies.
The spiracles lead into a network of tubes called the

trachea inside the body. Air enters through the spiracles
and then, passes through the trachea. Oxygen from this
air is absorbed by the tissues of the body. Carbon

Mosquito dioxide is removed from the body through the spiracles.

Fish, tadpoles and other aquatic animals breathe

through gills. They take in water through their
mouth. As this water passes through the gills,

oxygen from the water is absorbed and carbon Gills
dioxide is allowed to pass out. Tadpole

Blowhole
Whales and dolphins also live in water. They have lungs
which can take in oxygen from the air. So, they cannot
breathe under water, so they come up to the surface of

water to breathe. They breathe through blowholes
located on the top of their heads.

Dolphin

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