Respiratory system2

Respiratory System6th Grade Science

I. Function

A. Take in oxygen from airB. Remove carbon dioxideC. Provides Energy for all cellsD. SmellE. Water balanceF. Communication

II. Air Exchange

A. Inhaled Air1. Nitrogen 78%2. Oxygen 21%3. Carbon Dioxide 0.03%

B. Exhaled Air1. Nitrogen 78%2. Oxygen 16%3. Carbon Dioxide 4%

III. Pathway

A. Nose1. Hairs and mucus – Clean Air2. Nasal Membranes – Warm and moisten Air3. Sinuses – Air chambers

B. Uvula

1. Close off nose during swallowing

C. Pharynx

1. Throati. Shared with dig.

D. Larynx

1. Allows speech (vocal cords control)

E. Trachea

1. Wrapped in cartilage ring to keep open2. Cilia to sweep stuff out of lungs

i. Bring up to pharynx for swallowingii. Contract violently if irritated – sneeze

F. Bronchi

1. Branches into each lung2. Continued until reached end

G. Alveoli

1. Tiny sacs for gas exchangei. Oxygen into bloodii. Carbon dioxide into alveoli

2. Numbers – 300 million3. Area – 7 meters2

IV. Breathing

A. Two step process1. Inhalation

i. Ribs move outii. Diaphragm pulls down

2. Exhalationi. Ribs relaxii. Diaphragm relaxiii. Pull in intestines

V. Speech

VI. Damage and Disease

A. Smoking1. ~1,100 deaths every day2. 4,000 different chemicals

i. Tar – Chemicals that coat airwaysii. Carbon Monoxide – Replaces oxygen in bloodiii. Nicotine – Addictive stimulant

B. Asthma

1. Blocking of airways inappropriately1. Inhalers used to relax muscles

C. Bronchitis

1. Blocking of airways from pollution

E. Emphysema

1. Lung damage – No gas exchange

F. Lung Cancer

1. 400 people each day2. 53 cancer chemicals in cigarettes

G. Atherosclerosis

1. Tar chemicals harden arteriesi. Smokers have twice as many heart attacks