The Respiratory System

The Respiratory SystemFunctions:1.Brings oxygen into the body2.Removes carbon dioxide and water, from the body.

•We breathe about 6L of air every minute.– Air contains oxygen which is required for

respiration to take place in our cells.• Carbon dioxide and water are the waste products of

respiration.

Oxygen + Glucose = Carbon Dioxide + Water + Energy

The Respiratory System

NoseMouth

Larynx(Voice Box)

Lung

Diaphragm

Pharynx

Epiglottis

Trachea(Windpipe)

Bronchus

Alveoli

Nose and Moutho Two locations through which air enters the

respiratory system.– Which of these two locations is the BEST for you

to breathe through?• Why?

1. Air is warmed by blood flowing through capillaries in the inner lining of the nose.

2. Air is moistened by the mucus lining which prevents tissues from drying out.

3. Air is cleaned by tiny hairs that trap dust particles and microscopic organisms.

The Nose

o Air moves into the pharynx, located at the back of the throat.

• Location where the digestive and respiratory systems cross.

Food and air both travel through the pharynx.

o As air passes by the epiglottis and is directed down the trachea toward the lungs.

• Food would be directed into the esophagus when the epiglottis closes off the airway during swallowing.

The Pharynx

The Larynx

• After the pharynx is the larynx, voice box.o Vocal cords vibrate as air

passes through them to create sound. Men’s vocal cords are longer

thus deeper voices. Women’s vocal cords are

shorter thus higher pitched voices.

Stephen Tyler – 10:42 min

The Trachea

• The Trachea – (Windpipe)o passes by the epiglottis and is directed down the

trachea toward the lungs.o Alternating bands of cartilage and smooth

muscle make up the trachea.o Tiny hairs line the trachea and trap particles that

made it past the nose.

The TracheaLarynx

Cartilage Rings

Trachea

The Bronchi

• The lower end of the trachea splits into two tubes – Bronchi.– One directs air to the left lung and one to the

right lung.

Bronchi

The Lungs• Lungs are made up of smaller and smaller

tubes that eventually end in small grape-like clusters called alveoli.– Make up most of the tissue of the lungs.– Make the lungs soft and spongy.– Surrounded by capillaries and oxygen and carbon

dioxide are exchanged here by diffusion.

The Alveoli

Alveoli

OneAlveolus

Bronchiole

Capillaries

Lung Comparison

Lung Comparison

Normal Emphysema

Mechanics of Breathing

• Breathing in: (Inspiration/Inhaling)– Air pressure in your lungs is lower compared to

the air pressure outside your body.• Muscles attached to the ribs contract and pull up and

out.• The diaphragm, at the bottom of your chest, contracts

and pulls down.• Both actions make more room in your chest for the air

to rush in.

(Up & Out)

(Pulls Down)

(Air pressure is lower insideyour lungs compared to out =

Rushes In)

Mechanics of Breathing

• Breathing out: (Expiration/Exhaling)– Air pressure in your lungs is higher compared to

the air pressure outside your body.• Muscles in your chest relax, moving in and down.• The diaphragm relaxes, moving up.• Both actions reduce the amount of space available in

your chest cavity, forcing air out.

(Air pressure is higher insideyour lungs compared to out =

Rushes out)

(In & Down)

(Moves Up)