Download The Respiratory System

The Respiratory System
Just Breathe!
Interesting Facts
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The right lung is slightly larger than the left.
We lose half a litre of water per day
breathing.
At rest, the average adult takes in and
breathes out 6 litres of air each minute.
Breathing Experiments:
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Page 287 - Hold your breath
Page 287 - Breaths per minute
The average adult takes 12 breaths/min
In an average lifetime (74 years), does a person take
more breaths or heartbeats?
Heartbeats! 3 billion to 600 million breaths!
The Respiratory System:
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Respiration:
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all processes involved in the exchange of oxygen
and carbon dioxide between cells & the environment
O2
CO2
The Respiratory System:
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For Animal, Respiration Has 2 Purposes:
– To get oxygen (O2) to its cells
– To get rid of excess carbon dioxide (CO2)
O2
CO2
Types of Respiration: (P.289)
External Respiration In our Lungs!
 gas exchange between blood and the
surrounding air (Diffusion)
Types of Respiration:
Internal Respiration In our cells!
 gas exchange between blood and cells
(by diffusion also)
 Provides O2 for Cellular Respiration
Circulation of Oxygen
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Red Blood cells are O2 “Taxis”
They contain Hemoglobin!
When blood has a low O2 [ ](deoxygenated)
the hemoglobin is dark red/purple!
When blood has high O2 [ ](oxygenated) the
hemoglobin is bright red!
The LUNGS
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Massive amount of surface area…increased gas
exchange efficiency!
Ave. surface area = 70m2
Spread out flat, the lungs would provide enough
space for seven cars!
The word ‘lung’ comes from the Greek word
meaning ‘light’. Lungs are the only human organs
light enough to float!
The average male will breathe out enough air over
his lifetime to fill 250 two-person hot air balloons!
That’s a lot of hot air… [audience laughter]
You’ve got… 2:00
Structures:
Label
Them!
GO!!!
1:45
Structures:
1:30
Structures:
1:15
Structures:
1:00
Structures:
0:45
Structures:
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Structures:
0:15
Structures:
Time’s Up!!! 0:00
Structures:
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Nose
Mouth
Larynx
Lung
Rt. Bronchus
Diaphragm
Pharynx
Trachea
Lt. Bronchus
Bronchiole
Alveoli
External Respiration: Fxns!
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Nasal Passage: Air is warmed, humidified and
filtered & cleaned by cilia and mucous lining.
Oral Cavity: Passage of air
Pharynx: Common pathway for air and food.
Larynx: Adam’s apple. Produces sound (vocal
cords)
Trachea: Epiglottis opens allowing air to move
down the cilia and mucous-lined trachea to one
of two bronchi, heading to the lungs.
External Respiration: Fxns!
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Bronchi: Main branches of the trachea
Divide to form bronchioles, and air eventually
reaches tiny air sacs called alveoli.
Gas exchange occurs at the alveoli – O2 moving into
the blood, and CO2 moving out.
Oxygen is distributed to the cells of the body via the
blood (pumped by the heart!)
Ribs: protect the lungs and heart, aid in breathing.
Lungs: major organ of respiration
Gas Exchange @ the Alveoli
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Each alveolus is only one cell
thick and is very moist. This
facilitates diffusion!
240 alveolar membranes
stacked together would only be
as thick as a sheet of paper!
Each lung contains 150 million
alveoli!
Alveoli: Air Sacs!
External Respiration:
2 Phases:
 Inspiration
–
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diaphragm contracts and moves downward
(flattens), volume increases, creating low
pressure and drawing air in
Expiration
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diaphragm relaxes, volume decreases, creating
high pressure, forcing air out
The Diaphragm!
Complete Diaphragm Worksheet!!
Breathing Physiology
Quickly complete worksheet (use P. 297)
 Tidal Volume: Demo
 Vital Capacity
 Vital Capacity can be…
- Increased by training (i.e. swimmers ~6L)
- Decreased by smoking!
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Feedback Regulation
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The Medulla Oblongata is the control centre in the
brain!
CO2 levels in the blood increase, making the blood
acidic.
Chemoreceptors in the aorta and other large arteries
sense this change and relay a message to the brain.
Brain sends a message to the diaphragm and
intercostal muscles of ribs to increase breathing rate.
Homeostasis is restored!
Diseases & Health Problems:
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Obstructive Diseases (e.g., Emphysema,
Bronchitis, Asthma)
Restrictive Diseases (e.g., Cystic Fibrosis, Alveolar
Damage)
Vascular Diseases (e.g., Pulmonary Edema)
Infectious Diseases: (e.g., Pneumonia, Influenza,
Tuberculosis)
Environmental Irritants: (e.g., Asbestos, Particulate
Pollutants, SMOKING!)
F.Y.I.
Coughing is of major importance, as it is the bodies
main method to remove dust, mucus, saliva, and other debris
from the lungs. Inability to cough can lead to infection.
Treatment Options
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Asthma – Caused by
contracting muscles
that surround bronchi.
Air mov’t is restricted.
Puffers contain
“bronchodilators” that
relax the muscles.
Treatment Options
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Bronchitis & EmphysemaMucous layers are broken
down, dirt/particles collect in
lungs and damage alveoli.
Caused by smoking and other
environmental irritants (‘Darts’
contain ~4000 chemicals!).
Must use a portable O2 delivery
system to compensate for less
gas exchange surface.
Any one for a smoke?
Altitude Sickness
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High Altitude Pulmonary
Edema (fluid in the lungs) persistent dry cough, fever
and shortness of breath
even when resting
HAPE can lead to…
High Altitude Cerebral
Edema (swelling of the
brain) - headache that does
not respond to analgesics,
unsteady walking,
increasing vomiting and
gradual loss of
consciousness
Mount Everest – 8 848 m (29 028 ft)
Mount Everest
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May 12, 2006: Ed Viesturs became the first American to summit all
fourteen 8000m+ peaks without the use of supplemental oxygen!!
"I am nothing more than a single narrow gasping lung, floating over
the mists and summits." Reinhold Messner
Above 8000m is called the “Death Zone”
As of 2004, 2,238 people had reached the summit (1,148 of them
since 1998) and 186 people have died trying!
HAPE- Treatment
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Acclimatize: “Climb
high, Sleep Low”
Get to lower altitudes
quickly!