Download The Respiratory System. Presented by Toni Davis and Niamh

The Respiratory System.
Presented by Toni Davis and Niamh
McDonald
Function of the Respiratory System
What Does The Respiratory System Do?
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The respiratory system takes in oxygen to circulate
around the body for many uses such as creating
ATP, supplying systems with oxygen for smelling
and speaking.
Also, includes that fibers that filter particles from
the outside air to and from the lungs
Encompasses the whole process by which oxygen is
delivered to the cells and used to break down
glucose from food, releasing energy.
Structures of the Respiratory System
The Lungs
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They are covered by
fluid-filled double
transparent membrane
called the pleura.
Beneath the pleura is a
dome shaped muscle
structure called the
diaphragm which
contracts and relaxes to
expand and relax the
lungs.
The Bronchial Tree
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The bronchial tree
consists of branched air
passages that lead from
the trachea to the airs
sacs.
Nasal Cavity
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The nasal concha divide the nasal cavity into
passageways and help increase the surface area of the
mucous membrane. The mucous membrane with
hairlike projections called cilia, lines the nasal cavity
and moistens, filter and warms incoming air.
Particles caught in mucous is carried away to the
pharynx as a result of the ciliary action, and are
eventually swallowed.
Nasal Cavity
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The mucous traps
invading germs with
antibacterial enzymes,
cilia then allows for
mucous to be
swallowed.
Pharynx
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Behind nasal nasal
cavity, oral cavity, and
larynx
Passageway for air and
food
Consists of
nasopharynx,
oropharynx, and
larynopharynx
Larynx
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Conducts air and helps
prevent foreign objects
from entering the
trachea
Composed of muscles
and cartilages
Lined with mucous
membrane
Trachea
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Covered with a ciliated
mucous membrane
Cilia move mucus and
trapped foreign matter
to the pharynx
Bronchioles
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Bronchus branches
from the lower trachea
and carry air to the
lungs.
They divide into smaller
branches called
segmental bronchial ,
and subdivide smaller
and smaller into
bronchioles.
Alveoli
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Approx 600 million
Alveoli sacs exist on the
tips of bronchioles.
Capillaries in the walls
of Alveoli absorb
oxygen, and release Co2
and H2O to be exhaled.
Mechanics of breathing
Breathing Mechanism
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The action of breathing in and out is due to changes
of pressure within the thorax, in comparison with
the outside
When you inhale, intercostals muscles move rib
cage upwards and out
Increase in size and decreases internal pressure and
air from outside rushes into the lungs to equalize
the pressures
Breathing Mechanism
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When you exhale, the
diaphragm and
intercostal muscles relax
and return to their
resting positions
Reduces size of
Thoracic cavity,
increasing pressure and
forcing air out of the
lungs
The Pathway of air
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With each breath...
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Person clinches diaphragm, making a vacuum that air is
drawn into
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The air enters trachea moving through one of the two
bronchial tubes
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They branch into smaller into smaller bronchioles
ending in alveoli (small sacs)
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Alveoli contain capillaries in the walls. Red blood cells
that carry carbon dioxide from the body trades the
carbon for oxygen in air by diffusion
The Pathway of Air
(cont.)
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Oxygenated blood travels all over the body, supply
oxygen when needed
Diaphragm relax, carbon dioxide rushes out of the
alveoli, through bronchioles and bronchial tubes,
out of the trachea and out of the body
The Respiratory System in the brain
Respiratory Center of The Brain
Groups of neurons scattered through the pons and
Medulla Oblongota make up the respiratory center
of the brain.
The Medullary Rhythmycity area have two neuron
groups: Dorsal and Ventral that extend the length of
the Medulla Oblongota
Dorsal Respiratory
This controls the basic rhythms of inspiration.
Neurons emit bursts of impulses that signal the
Diaphragm and the other breathing muscles to
contract.
Ventral Respiratory
This group usually is very quiet when breathing
normally, but if you are more active and have more
forceful breathing, like in exercise, this group is
activated.
Function and structure of Respiratory Membrane
Respiratory Membrane
The respiratory membrane is absorbent tissue where
gases are exchanged between alveolar air and the blood
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4 Layers of the Respiratory Membrane
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Alveolar epithelial wall
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Alveolar epithelial basment membrane
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Capillary basement membrane
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Endothelial cells of capillaries
Air and blood gas exchange
Gas Exchange
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Blood that is low in
oxygen is pumped from
the right side of the heart,
through pulmonary veins
External respiration
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Carbon dioxide fuses from
the Pulmonary Capillaries
into the alveoli, oxygen
diffuses from the alveoli
into the pulmonary
capillaries
Internal Respiration
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Internal Respiration
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Oxygen-rich blood is pumped through the systemic
circuit to tissues throughout the body.
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Internal respiration occurs within tissues, as oxygen
diffuses from the systemic capillaries into the cells, and
carbon dioxide diffuses from the cell and into the
systemic circuit.
External Respiration
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Each breath draws
down through the
bronchi and
bronchioles into the
alveoli. Here, in the air
sacs, occurs the central
process of external
respiration.
Oxygen & Carbon dioxide transportation
How Oxygen diffuses
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Usually, air is about 78% Nitrogen, 21% oxygen, and
0.04% Carbon Dioxide
When air is inhaled, the gas molecules are filtered through,
come into the Alveoli, and dissolve into the blood stream
and diffuse with the stream in areas of differentiating
pressure.
98% of oxygen binds to the Iron in Hemoglobin, and is
pumped through the body by the heart. The other 2% of
Oxygen dissolves into the plasma
Oxygen Increase
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Oxygen is released faster over time as the Carbon Dioxide
concentration increases, the environment becomes more acidic, or as
blood temperature increases. This is why you breathe harder to bring
in more oxygen when exercising
Blood flow picks up Carbon Dioxide and transported in three different
forms.
Some dissolves into plasma, some attach to Hemoglobin and makes its
way back out to the lungs, and the third becomes Bicarbonate ions.
CO2 bonds to the amino acids in Hemoglobin, and can be carried out
on Hemoglobin with Oxygen already on it.
Bicarbonate Ions
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The Bicarbonate ions are when CO2 react with
H2O to create a carbonic acid, then results in the
ions. This then travels out with the blood stream,
through capillaries of the lungs, dissolves in the
alveoli, and exhaled.
Rate of Diffusion depends on
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Partial pressure difference
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Large surface area of alveoli
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Diffusion distance (Membrane thickness)
Factors that affect breathing
Factors that affect breathing
Asthma: Narrowed airways
caused by an allergic reaction
(i.e Dust, Pollen, Smoke).
Infections or a large amount
of physical activity can cause
an attack.
Whooping Cough: Attacks
the Bronchi, inflame lung
tissues, and create thick
fluid to weaken breathing.
Factors that affect breathing
Tuberculosis: Bacterial
infection of the lung
cavities, and potentially
fatal.
Bronchitis: Inflammation of
Bronchi and coughing of
yellow mucosa fluid.
Pneumonia: Inflammation of
lungs from infection. Parts
of lungs fill with fluid and
become airless.
The End
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You have five to ten minutes to study before taking
the quiz.