Transcript File - Biology with Radjewski

Respiratory System
Taking in oxygen and getting rid of
the carbon dioxide that’s not needed
Methods of Respiration
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Diffusion/Respiratory surfaces
Gills
Tracheae
Air Sacs
Book Lungs
Lungs
Diffusion/Respiratory Surfaces
• Single celled organisms
• Diffusion Limits their size to small
• Respiratory surfaces increase surface area
for gas exchange; they are covered with
moist epithelial cells
• Sponges/jellyfish take gases in directly
from water
• Flatworms/annelids use outer surface for
gas exchange
Gills
• Arthropods, fish and amphibians
• Contain blood vessels with a thin epithelial
layer
• Can be external (some amphibians) or
internal (crabs and fish)
• Water flows over gills in one direction
while blood flows in the opposite direction
through gill capillaries. This countercurrent
flow maximizes oxygen transfer
Tracheae
• Series of tubes that carry air directly to cells
for gas exchange
• Spiracles are openings at the body surface
that lead to tracheae that branch into smaller
tubes known as tracheoles
• tracheae will not function well in animals
whose body is longer than 5 cm
• Ex. grasshopper
Air Sacs
• Air sacs are found as tiny sacs off the
larger breathing tubes (tracheae) of
insects, as extensions of the lungs in
birds, and as end organs in the lungs of
certain other vertebrates.
• They serve to increase respiratory
efficiency by providing a large surface
area for gas exchange.
Book Lungs
• terrestrial respiratory organ
characteristic of arachnids such as
scorpions and spiders.
• Each book lung consists of hollow flat
plates.
• Air bathes the outer surface of the
plates and blood circulates within them,
facilitating the exchange of gases. In
most species, adequate gas exchange
occurs without any muscular movement
to ventilate the lung.
Lungs
• In the lungs oxygen is taken into the
body and carbon dioxide is breathed
out.
• made of spongy, elastic tissue that
stretches and constricts as you breathe.
• The airways that bring air into the lungs
(the trachea and bronchi) are made of
smooth muscle and cartilage, allowing
the airways to constrict and expand.
Where the air goes
• As you breathe air in through your nose
or mouth, it goes past the epiglottis
and into the trachea.
• It continues down the trachea through
your vocal cords in the larynx until it
reaches the bronchi.
• From the bronchi, air passes into each
lung. The air then follows narrower and
narrower bronchioles until it reaches
the alveoli.
What happens next?
• Within each alveoli, the oxygen concentration
is high, so oxygen passes or diffuses across
the alveolar membrane into the pulmonary
capillary.
• At the beginning of the pulmonary capillary,
the hemoglobin in the red blood cells has
carbon dioxide bound to it and very little
oxygen.
• The oxygen binds to hemoglobin and the
carbon dioxide is released. Carbon dioxide is
also released from sodium bicarbonate
dissolved in the blood of the pulmonary
capillary.
• The concentration of carbon dioxide is
high in the pulmonary capillary, so
carbon dioxide leaves the alveolus
when you exhale and the oxygenenriched blood returns to the heart.
• Thus, the purpose of breathing is to
keep the oxygen concentration high and
the carbon dioxide concentration low in
the alveoli so this gas exchange can
occur!
Lets see the diagram
• First the body
breathes in the air
which is sucked
through the nose or
mouth and down
through the trachea
(windpipe). The
trachea is a pipe
shaped by rings of
cartilage. It divides
into two tubes called
bronchi. These carry
air into each lung.
What does a lung look like?
• Inside the lung, the
tubes divide into
smaller and smaller
tubes called
bronchioles. At the
end of each of
these tubes are
small air sacs called
alveoli.
Alveoli
• Capillaries, which are
small blood vessels with
thin walls, are wrapped
around these alveoli.
The walls are so thin
and close to each other
that the air easily seeps
through. In this way,
oxygen seeps through
into the bloodstream
and carbon dioxide, in
the bloodstream, seeps
through into the alveoli,
and is then removed
from the body when we
breathe out.
Breathing in and out
• The diaphragm is
the muscle that
controls the
breathing process.
As the diaphragm
flattens it causes the
chest to expand and
air is sucked into the
lungs. When the
diaphragm relaxes,
the chest collapses
and the air in the
lungs is forced out.
Diseases of Respiratory System
• Asthma: The bronchioles constrict, reducing
the size of the airways. This cuts down on the
flow of air and makes the respiratory muscles
work harder.
• Emphysema: The lungs become stiff with
fibers and become less elastic, which
increases the work of the respiratory muscles.
• Bronchitis: The airways become inflamed
and narrower, which restricts the flow of air
and increases the work of the respiratory
muscles
• Apnea: Breathing slows or stops under a
variety of conditions. There are many types of
apnea, and they are usually caused by
problems in the respiratory centers of the
brain.
• Smoke inhalation: Smoke particles coat the
alveoli and prevent the exchange of gases.
• Carbon monoxide poisoning: Carbon
monoxide binds to hemoglobin more tightly
than either oxygen or carbon dioxide, which
minimizes the delivery of oxygen to all the
tissues of the body, including the brain, the
heart and muscles.
Fun Facts!!!!!!!!
• Your lungs contain almost 1500 miles of
airways and over 300 million alveoli.
• Every minute you breathe in 13 pints of air.
• People tend to get more colds in the winter
because we're indoors more often and in
close proximity to other people. When
people sneeze, cough and even breathe -germs go flying
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
More fun Facts!!!!!!!!!!!!!
• Left lung is smaller to leave room for the
heart!
• You breathe over 5000x a day!
If water is made up of hydrogen and oxygen,
why can't we breathe underwater?
• Humans cannot breathe underwater
because our lungs do not have enough
surface area to absorb enough oxygen
from water, and the lining in our lungs is
adapted to handle air rather than water.