Transcript Human Respiratory System

Mrs. Degl
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What is Human Respiration?
• The human respiratory
system allows one to obtain
oxygen & eliminate carbon
dioxide.
• Breathing consists of two
phases, inhalation and
exhalation.
– Inhalation- the process of
taking in air
– Exhalation- the process of
blowing out air
Humans have 2 lungs. Lungs are made up of a
bronchus and it’s bronchioles, and alveoli.
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Organs in the Respiratory System
STRUCTURE
FUNCTION
nose / nasal cavity
warms, moistens, & filters air as it is
inhaled
pharynx (throat)
passageway for air, leads to trachea
larynx
trachea (windpipe)
bronchi
the voice box, where vocal chords are
located
keeps the windpipe "open"
trachea is lined with fine hairs called
cilia which filter air before it reaches the
lungs
two branches at the end of the trachea,
each lead to a lung
bronchioles
a network of smaller branches leading from
the bronchi into the lung tissue &
ultimately to air sacs
alveoli
the functional respiratory units in the lung
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where
gases are exchanged
Gas Exchange
The air that enters the alveoli is rich in oxygen. The blood in
the capillaries surrounding the alveoli is oxygen-poor and
contains wastes of cellular respiration (carbon dioxide and
water). The oxygen diffuses from the alveoli into the blood,
where it enters the red blood cells. Next the oxygen diffuses
out of the capillaries into the body cells.
Carbon dioxide and water
diffuse out from the cells into
the blood. When the blood
returns to the lungs, these
wastes diffuse into the alveoli
and are expelled from the
body in the exhaled air.
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Breathing Rate
•The breathing rate or respiratory rate is the number
of breaths a living being, such as a human, takes per
minute.
•The medulla of the brain controls breathing.
•When the carbon dioxide levels in the body are
high, a signal is sent from the brain to the ribs and
diaphragm to increase breathing rate.
•As the carbon dioxide levels in the body decreases,
the body will slow the breathing rate again.
•This is an example of a feedback mechanism
(helps keep the body at homeostasis).
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Disorders of the Respiratory System
•Bronchitis is an inflammation of the linings of the bronchial
tubes. Because of swelling, air passages become
narrowed and filled with mucus, causing breathing
difficulties and coughing.
•Asthma is an allergic reaction producing narrowing of the
bronchial tubes, causing difficulty breathing. Asthma
cannot be cured, but most people with asthma can control
it so that they have few and infrequent symptoms and can
live active lives.
•Emphysema is a disease in which the walls of the alveoli
break down, decreasing the surface area for gas
exchange, causing shortness of breath and decreased
breathing and lung capacity.
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Mrs. Degl
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Why Do I Yawn?
When you are sleepy or drowsy the lungs do not take enough oxygen
from the air. This causes a shortage of oxygen in our bodies. The brain
senses this shortage of oxygen and sends a message that causes you to
take a deep long breath---a YAWN.
Why Do I Sneeze?
Sneezing is like a cough in the upper breathing passages. It is the
body's way of removing an irritant from the sensitive mucous membranes
of the nose. Many things can irritate the mucous membranes. Dust, pollen,
pepper or even a cold blast of air are just some of the many things that
may cause you to sneeze.
What Causes Hiccups?
Hiccups are the sudden movements of the diaphragm. It is involuntary -- you have no control over hiccups, as you well know. There are many
causes of hiccups. The diaphragm may get irritated, you may have eaten
to fast, or maybe some substance in the blood could even have brought on
the hiccups.
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