The document describes the human respiratory system. It includes diagrams of the major structures like the nose, mouth, pharynx, larynx, trachea, bronchi, bronchioles and lungs. It defines respiration as the process of gas exchange between oxygen and carbon dioxide in the blood and alveoli. Breathing is controlled by the medulla oblongata which monitors carbon dioxide levels and signals the diaphragm to contract and expand the lungs during inhalation. Oxygen diffuses into blood capillaries surrounding each alveolus while carbon dioxide diffuses out, allowing for gas exchange.

1. The Respiratory System
Copyright Pearson Prentice Hall

2. The Human Respiratory
System
Pharynx
Nose Larynx
Mouth Trache
aLungs
Epiglottis
Bronchus
Bronchioles
Diaphragm
Copyright Pearson Prentice Hall

3. What Is Respiration?
What Is Respiration?
In biology, respiration means different things.
Cellular respiration is the release of energy
from the breakdown of food in the presence of
oxygen
(occurs in the?????)
At the organism level, respiration is the process
of gas exchange—the release of carbon
dioxide and the uptake of oxygen that occurs
between RBCs and alveoli
Breathing is the actual mechanical intake of air
Copyright Pearson Prentice Hall

4. Breathing
BREATHING
Lungs are sealed
in pleural
membranes
inside the chest
cavity.
At the bottom of
the cavity is a
large, flat muscle
known as the
diaphragm.
Copyright Pearson Prentice Hall

5. Breathing
During inhalation, the
diaphragm contracts and
the rib cage rises up.
This expands the volume of
the chest cavity.
The chest cavity is sealed,
so this creates a partial
vacuum inside the cavity.
Atmospheric pressure fills
the lungs as air rushes into
the breathing passages.
Copyright Pearson Prentice Hall

6. Breathing
Often exhaling is a Air Exhaled
passive event.
When the rib cage Rib cage
lowers
lowers and the
diaphragm relaxes,
pressure in the chest
cavity is greater than
atmospheric
pressure.
Air is pushed out of Exhalation
the lungs. Copyright Pearson Prentice Hall

7. Copyright Pearson Prentice Hall

8. How Breathing Is Controlled
How Breathing Is Controlled
Breathing is controlled by
the medulla oblongata.
The medulla oblongata
monitors carbon
dioxide in the blood.
As carbon dioxide
increases, nerve
impulses make the
diaphragm contract,
bringing air into the
lungs.
The higher the carbon
dioxide level, the
stronger the impulses.
Copyright Pearson Prentice Hall

9. So what’s a hiccup?
Longest bout of hiccups – 68 years!!!
Check out IPp 50 for more info!
Copyright Pearson Prentice Hall

10. Lung Capacity Lab!! (we’ll do next class)
Objective
Measure the amount of air your lungs can hold
Copyright Pearson Prentice Hall

11. The Human Respiratory System
RESPIRATION
Alveoli are grouped in
clusters. Pulmonary
artery
A network of
capillaries surrounds
each alveolus. Pulmonary
vein
Capillaries
Copyright Pearson Prentice Hall

12. Gas Exchange
RESPIRATION O2
Gas exchange takes place
in the alveoli.
Oxygen diffuses into the CO2
blood.
Carbon dioxide in the
blood diffuses into the
alveolus.
Let’s examine this up close
Capillary
Copyright Pearson Prentice Hall