The Respiratory System

Breathing• the process of taking in air into our bodies and giving it out again.

• is to take in oxygen which is used for the process of respiration.

• also removes carbon dioxide (produced during respiration) from our bodies and releases it to the air.

The parts of a living thing that help it to breathe form the respiratory system.

Different living things have different parts in their respiratory systems.

Living Things Respiratory Systems

Fish Gills

Amphibian Lungs, Skin or Gills

Plants Stomata

Worms Moist Skin

Respiratory in Human Body

When you breathe in, your ribs move out and upwards. Your diaphragm, a thin sheet of muscle moves downwards. This causes your chest to become bigger.

When you breathe out, your ribs move in and downwards. This time, your diaphragm moves upwards. This causes your chest to become smaller and the air that has carbon dioxide in it, is forced out of your lungs.

This is how the lungs expand itself when the air enters or exits from it.

Respiration in Human Body

When you breathe in,

• Air enters into the your body through your nose or your mouth.

• Air is cleaned, warmed and moistened.

Respiration in Human Body

When you breathe in,

• Air then moves into the windpipe.

• The windpipe has tiny hair that traps dust particles found in the air.

Respiration in Human Body

When you breathe in,

• Air enters the left and right into 2 smaller tubes.

• Tubes branch further into tiny tubes that end in balloon-like air sacs.

An Alveoli – Air Sac

When the air you breathe in reaches your air sacs, oxygen passes through the walls of the sacs into the blood vessels.

Air Sac

Blood Vessel

The blood then carries the oxygen to all parts of your body.

An Alveoli – Air Sac

Air Sac

Blood Vessel

At the same time, carbon dioxide from the blood passes through your blood vessel into the air sacs. Carbon dioxide mixes with the air in your air sacs.