Page 168 - Science Class 06

Breathing: Breathing is the process in which This process is called photosynthesis.
animals take in oxygen and give out carbon
dioxide. Different kinds of animals have
different kinds of organs for breathing. In
human beings, breathing organs are nasals
or nostrils, wind pipe, a pair of lungs and
bronchi. Fishes have gills to breathe.
Nasal Cavity
Oral Cavity
Pharynx
Larynx
Trachea
Bronchi Le
Lung
Right
Lung
Breathing
v Release of Energy : Respira on takes
place inside the cells and ssues of the
body. When oxygen reaches the cells it
combines with glucose (sugar) into
which food had been converted. Energy
is released together with the waste
products of carbon dioxide and water.
Glucose + Oyxgen Water + Carbon
dioxide + energy
Why Do Plants Need Air?
Plants also need air to respire. Plants do not
breathe like animals. Atmospheric carbon
dioxide move in and out by simple diffusion,
through the small pores (stomata) on the
leaves and prepare their own food with the
help of sunlight, carbon dioxide and water.
168
During the process of photosynthesis, plants
also release oxygen.
Glucose
(sugar)
+
Sunlight Oxygen
+
Carbon dioxide
+
Water
Photosynthesis
Leaves take in air through small pores
present in them called stomata.
How do Aqua c Animals and Plants Take in
Air?
The shapes and sizes of water animals are
different that of animals living on land. But
they also need air to live. Most of the water
animals have gills for breathing.
For example, fishes take in oxygen dissolved
in water through their gills. Aqua c plants
release oxygen in water during the process
of photosynthesis. This oxygen mixes up
with water which is taken by the water
animals.
Fish takes in oxygen dissolved in water.
Smiliarly, carbon dioxide released by water
animals is taken by the water plants.
Science-6