Lungs and Respiratory systemHow do we get oxygen into the body?

Why do we need oxygen? Aerobic cells need oxygen to make energy

(remember the yeast lab?)

Human Respiratory system Path of oxygen:

Mouth/nose pharynx larynx trachea bronchi lung

Lungs have these parts: Bronchi bronchioles alveoli

Nose Function: prevent dust from getting

into the lungs.

Structures:

Hair traps dust

Mucus traps dust

Pharynx (again!) Function: prevent food getting into

the lungs

Structure: epiglottis, flap, closes when you swallow

Larynx Function: speaking

Structure: contains the vocal cords

trachea Function: passage of air

Structure: surrounded by cartilage

Bronchi Function: passage of air

Two tubes that split from the trachea

Bronchioles Function: passage of air

Structure: separates into smaller branches

alveoli Function: site of gas exchange

Structure: very thin walls, surrounded with capillaries.

Gas is carried in the blood by hemoglobin in RBC’s

Breathing The diaphragm is the muscle

responsible for breathing

When it contracts it expands the chest cavity. Negative pressure pulls air into the lungs

http://www.youtube.com/watch?v=hp-gCvW8PRY

Breathing Breathing is controlled not by how

much oxygen you have but by much CO2 is in your blood.

What can you do to hold your breath longer?

Smoking and lung cancer?