Transcript The Human Respiratory System

The Human Respiratory System
Biology 314
Mr. Doron
Game Plan
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Introduction to the respiratory system
Pathway the air takes
Role of the nasal cavity
Role of the pharynx
Role of the epiglottis
Role of the trachea
Role of the bronchi & lungs
Fun FAQ’s (yawning, sneezing, hiccups)
Respiratory System
Nasal Cavity
Mouth
Trachea
Bronchioles
Lung
Diaphragm
Human Respiratory System
 The respiratory system has two parts
 The respiratory airways (nasal, cavity,
pharynx, trachea, bronchi)
 The lungs
 What pathway does air take in the
respiratory system?
 Nasal cavity --> pharynx --> trachea -->
bronchi --> lungs
What is the role of the nasal
cavity?
 Hairs: filters out the largest foreign particles
in the air that enters the nostrils
 Capillaries: warm up the air that is inhaled
 Mucous glands: moisten the air
The Role of the Pharynx
 Pharynx: crossover point (for the digestive
and respiratory tracts).
 collects incoming air from the nose and
passes it downward to the trachea
(windpipe).
The Role of the Epiglottis
 Known as the switching mechanism
 It is a flap of tissue that guards the entrance
to the trachea, closing when anything is
swallowed that should go into the
esophagus and stomach
What is the role of the trachea?
 The larynx is situated at the upper end of
the trachea.
 Contains vocal chords
 In males it’s the adam’s apple.
Role of the Trachea Con’t
 The walls of the trachea are lined with numerous
cilia (hair) and mucous glands
 The mucus secreted by the mucous glands capture
the foreign particles that have escaped nasal
filtration.
 The beating of the cilia move the particles now
coated with mucus back to the pharynx.
 At the pharynx, they are either swallowed down
the esophagus or expelled from the respiratory
tract.
Role of the Pharynx
 Serve as the crossover point
 Serves as the pathway that either
 Air enters the respiratory tract or
 Food enters the esophagus
Role of the Bronchi
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Extensions of the trachea
Branch into the bronchioles
Carry air to the lungs
Have cilia and mucous glands
Role of the Lungs
 Each bronchus enters a lung and branches
into smaller bronchi known as bronchioles.
These in turn subdivide into millions of
alveoli.
 Alveolus is the functional unit of the lungs
 It is here that venous blood (carbon –
dioxide carrying blood) is oxygenated to
become arterial blood (oxygen carrying
blood)
 Thus, oxygen enters the alveolus
 Carbon dioxide leaves the alveolus
A Picture is Worth 1000 words
Chest
Anatomy
More Pictures
X ray of
human chest
Work in Class / Homework
Do Page 83, 84 & 85. Copy in your notes #1-
 Air
 The ribs
 Intercostal muscles
 Enters the body
 Move out and up
 Contract, moving the
rigs up and out, the
diaphragm contacts
and moves down
Why Do You Yawn?
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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 You 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.