Transcript 1.2.3: A healthy, active lifestyle and your respiratory system

1.2.3: A healthy, active lifestyle
and your respiratory system
L.O
1.Understand the structure of the lungs
2.Understand the function of the
respiratory system
• The respiratory system is everything we
use to breath.
• You need to be able to understand how
we breath to get oxygen into the body and
to get rid of waste carbon dioxide.
• The Trachea is split up into two bronchus
that leads into both our lungs.
• The bronchi are further distributed into
bronchioles.
• The air travels along these tubes and
finally ends up in the air sacs (alveoli).
• The air sacs are surrounded by a network
of capillaries and as the blood flows
through these capillaries, the oxygen in
the air sacs(alveoli) diffuse into the blood,
thus reoxygenating them.
The diaphragm
As we breathe in (Inhale),
• the diaphragm contracts and depresses so that
a lot of air enters and fills up the lungs.
• The ribs are therefore raised.
• The Diaphragm moves downwards
• When we breathe out (Exhale),
• the ribs return to their original position and the
diaphragm relaxes and arches upwards.
• The air is forced out of the lungs and returns the
same way it came.
• The path the air takes back out is very
similar, except that this time round, the
blood meets the air sacs and carbon
dioxide diffuses out. This carbon dioxide
finally returns to the atmosphere when we
exhale.
How we breath
• Inspiration - Breath in
• When you inhale:
• the intercostal muscles contract,
expanding the ribcage.
• the diaphragm contracts, pulling
downwards to increase the volume of the
chest.
• pressure inside the chest is lowered and
air is sucked into the lungs.
How we breath
• Expiration - Breath out
• When you exhale:
• the intercostal muscles relax, the ribcage
drops inwards and downwards
• the diaphragm relaxes, moving back
upwards, decreasing the volume of the
chest.
• pressure inside the chest increases and
air is forced out.
Gaseous exchange
• Gas is exchanged from the air into the
blood stream in the alveoli (tiny air sacs).
• Waste carbon dioxide is transferred from
the blood back into the air also.
Respiration
• Respiration is the release of energy from
glucose in the muscles.
• When the body is at rest this
is aerobic respiration. As you exercise
you breathe harder and deeper and the
heart beats faster to get oxygen to the
muscles.
• Glucose + oxygen → energy + water +
carbon dioxide
Respiration
• When exercising very hard, the heart
cannot get enough oxygen to the muscles.
Respiration then becomes anaerobic.
• Glucose → energy + lactic acid
• Vital capacity is the most air you can
breath in or out in one breath.
Short term effects
1. You breath more quickly
2. You also breath more deeply (take in larger
volumes of air each breath)
3. If your doing anaerobic activity then lactic
acid will begin to build up in your muscles
4. When you stop exercising anaerobically your
body will continue to breath heavily to get rid of
the lactic acid by repaying the 'oxygen debt'.
5. Respiratory rate increases. The number of
breathes per minute
Long term effects
1. The muscles around your chest cavity get
stronger - so they can make your chest
cavity larger
2. With a larger chest cavity you can
breath in more air in one breath
(increase vital capacity)
Long terms effects
3.Your lungs get more efficient at exchanging gas
into and out of the blood stream.
4.Develop more alveoli so greater gaseous
exchange can take place
5. This means you have a better oxygen supply to
the body which means you should be able to
exercise for longer.