Respiratory SystemMXMS 7th Grade Science

What is respiration?• the act of breathing, where oxygen is inhaled and

carbon dioxide is exhaled

Main Functions

• to carry oxygen to your lungs, where it is transferred into your bloodstream

• to carry carbon dioxide away from your lungs, where it can be exhaled

Interesting Facts• your lungs are not the same size, to make room for

your heart

• we take about 12-15 breaths per minute

• we lose about 0.5 Liter of water through breathing

Main Parts• Nasal passage & Mouth

• Pharynx

• Larynx

• Trachea

• Epiglottis

• Lungs

A. Bronchi

B. Bronchioles

C. Alveoli

D. Diaphragm

Nasal Passage & Mouth

• both allow air (O2 & CO2) to enter and leave the body

• nasal passage warms, filters, & moistens the incoming air

Pharynx• tubular area which allows passage of air into the

lungs

• tonsils are located here (part of the immune system)

Larynx

• controls the flow of air at the time of breathing

• aka: the voice box

Trachea

• tube which carries air from the throat into the lungs

• very rigid, lined with cartilage rings meant to keep it open at all times

Epiglottis

• flap-like structure which prevents food or water from entering the trachea when swallowing

Lungs• Bronchi: one of two passages which

allows air to flow into a lung (right or left)

• Bronchioles: much narrower tubes allowing air to pass from the bronchi to the alveoli

• Alveoli: individual hollow sacs that act as the surface for O2 & CO2 to be exchanged with the bloodstream

• Diaphragm: large muscle under the lungs that expands & contracts to force air in & out of the lungs

Hiccups

• occurs when the diaphragm begins to spasm

Respiratory Disorders

• COPD (Chronic Obstructive Pulmonary Disorder)

• Asthma

• Cystic Fibrosis

• Cancer

COPD• Chronic Obstructive Pulmonary Disorder can refer

to emphysema or chronic bronchitis

• caused by damage to the airways that carry air to & from the lungs

Asthma• caused by triggers (environmental, etc.) that cause

airways to suddenly tighten and make it hard to breathe

Cystic Fibrosis

• genetic disease that can be fatal

• makes it hard to clear lungs of bacteria

Cancer• can be caused by smoking (lung cancer) or

chewing tobacco (mouth/esophageal cancer)

• can be caused by exposure to airborne chemical/toxins