The Respiratory System
Describe the connection between the
circulatory and respiratory systems.
• Pulmonary Arteries pick up Oxygen and drop
off carbon dioxide at the lungs
• Pulmonary Veins carry oxygenated blood back
to the heart
The Lungs
What is the difference between
external and internal respiration?
•External: exchange of
oxygen and carbon
dioxide between the
AIR, BLOOD, and
LUNGS
•Occurs OUTSIDE of
cells
What is the difference between
external and internal respiration?
•Internal: Cellular
Respiration – occurs
inside of cells
•Oxygen and Carbon
dioxide are exchanged
between body cells and
capillaries, energy is
produced
Weird Science Facts
• You breathe about
21,600 times every day
• If you spread out your
lungs, they would
cover the floor of a
tennis court
• Men can hold about 6
quarts of air in their
lungs; Women can
hold 4.5 quarts
Respiratory System
Nasal Cavity
Mouth
Trachea
Bronchi
Bronchioles
Lung
Alveoli
Diaphragm
7
What is the pathway that air follows
as it travels through the respiratory
tract?
•Mouth/Nasal Cavity
•Pharynx
•Larynx
•Trachea
•Bronchi
•Bronchioles
•Alveoli
The Lungs
Nose/Nasal Passageway or Mouth
• Air enters the nose
and is filtered,
warmed, and
moistened
• Why?
To change the
temperature of
the air to match
body
temperature!
Pharynx
• Tubelike passageway
for food and air
• Back of the throat
Larynx
• Location of vocal
cords
• Air must pass over
them when we speak
to make sound
**What structure
prevents food
from entering the
respiratory
system?**
EPIGLOTTIS!!
Trachea (Wind Pipe)
• Made up of
cartilagenous rings
to keep airway open
• Lined with cilia and
mucus
**What is the role of the
cilia and mucus?
To prevent dust and
pathogens from
entering the lungs
Cilia and Mucus in the Trachea
Bronchi
• Two short branches at
the bottom of the
trachea
• Carry the air we
breathe into the lungs
Bronchioles
• Smaller tubes that
branch out from the
bronchi
Alveoli
• Tiny (grape like) air
sacs at the end of the
bronchioles
• Greatly increases the
surface area of the
lungs
• Surrounded by
capillaries
• RESPIRATORY
SURFACE: site of gas
exchange
Gas Exchange at the Alveoli
• CO2 and O2 are exchanged between capillaries
and alveoli by the process of diffusion
• Oxygen enters the blood
• Carbon Dioxide enters the alveoli
Alveoli
Alveoli
What is the diaphragm?
• Flat muscle on the floor of the chest
• Involved in breathing
• Contracts when inhaling, Relaxes when exhaling
Inhalation
• RIBS: move up and out
• DIAPHRAGM: contracts
(moves down)
• CHEST CAVITY: becomes
larger
• AIR PRESSURE: decreases,
and AIR ENTERS!
Exhalation
• RIBS: drop
• DIAPHRAGM: relaxes
(moves up)
• CHEST CAVITY:
becomes smaller
• AIR PRESSURE:
increases, and AIR EXITS!
Breathing
Breathing
Breathing
How is CO2 carried to the lungs by
the blood? (Three Ways)
• 70% of the CO2 will combine with water and
form carbonic acid (H2CO3)
• 20% will combine with hemoglobin
• 10% is dissolved in the plasma
The Breathing Rate is
controlled by:
• Concentration of carbon dioxide
• Center in brain
Regulation of Breathing:
Breathing Rate is controlled by the amount of
CO2, not O2!!
Exercise
CO2 H2CO3 Blood pH
Breathing Rate
Do Now: Label the Structures
Diseases
• Asthma
• Bronchitis
• Emphysema
• Lung Cancer
• Pneumonia
Asthma
32
Asthma
• What causes it?Allergic
reaction
• What happens? Bronchial
tubes become constricted
because of swelling;
prevents O2 from reaching
the lungs
• TREATMENT: Inhaler
Bronchitis
34
Bronchitis
• What causes it? Bacterial
infection
• What is it? Inflammation of
the bronchial tubes (swollen
and clogged with mucus)
• TREATMENT: Antibiotics
Emphysema
36
Emphysema
• What is it? Lung
disease, alveoli break
down and cannot
hold as much air.
• TREATMENT:
No cure, damage
can’t be undone.
Smoking
• Cigarette smoke contains nicotine, CO, and
tar.
• Smoking paralyzes the cilia in the respiratory
tract, preventing harmful particles and
mucus from being swept out.
• Also causes swelling and inflammation of the
respiratory surfaces.
Damage to Cilia and Mucus
Pneumonia
40
Pneumonia
• What causes it? Viral
or Bacterial infection
• What is it? Alveoli
become filled with fluid
and gas exchange is
prevented.
• TREATMENT:
Antibiotics
Lung Cancer
• What causes it? DNA
mutation resulting in…
• What is it? Uncontrolled cell
growth and tumor formation
• How is it treated? Radiation,
chemotherapy, transplant