Transcript BASIS NEEDS OF LIVING THINGS

The Human
Breathing System
This system includes the lungs,
pathways connecting them to the
outside
environment,
and
structures in the chest involved
with moving air in and out of the
lungs.
We
inhale oxygen and
exhale carbon dioxide
Breathing
process
involves inhalation and
exhalation.
What
is Inhalation?
 The
process of breathing air into the
lungs through the mouth and/ or nose
What
 The
is exhalation?
movement of air out of the lungs
to the external environment during
breathing.
Oxygen
Nose/
mouth
Windpipe
Lungs
Carbon
Dioxide
Lungs
Windpipe
Nose/ mouth
Air enters the
body through the
nose, is warmed,
filtered, and
passed through
the nasal cavity
Air passes the
pharynx and
then to larynx.
•After passing the
larynx, the air
moves into the
bronchi that carry
air in and out of
the lungs.
•Bronchi
branch
into smaller and
smaller
tubes
known
as
bronchioles.
Bronchioles
terminate in grapelike sac clusters
known as alveoli.
•
•Alveoli
are
surrounded by a
network of thinwalled capillaries.
When you breath in:
3.
1. The intercostals muscles
contract. These pull the
ribcage upwards. So the
chest increase in volume.
2.
As the chest gets larger
internal air pressure in the
lungs and thoracic cavity
becomes less than outside
atmospheric pressure . This
pressure difference ,forces air
down the windpipe into the
lung
The diaphragm
contracts. This makes
it flatten out, so the
chest gets even larger.
When you breathe out:
1. The intercostal muscles
relax, which lowers the
ribcage. The chest
decrease in volume.
2. The diaphargm relaxes,
and buges upwards. This
decreases the volume of
the chest even more.
3.
Because the chest has
got smaller, air pressure
becomes more than
outside, and air forced
out of the lungs.
 respiration.flv