Respiratory System

RespirationThe energyreleasing process

that is fueled byoxygen.

Function of the Respiratory

System

To get oxygen into the body & remove carbon dioxide and water from the body.

Diagram of Upper & Lower Respiratory Systems

UPPER RESPIRATORYSYSTEM

• nose• nasal cavity

• pharynx

The Nose • Air enters through 2 openings called nostrils

• Wall of cartilage separates the 2 nostrils

• Air is heated by warm blood flowing through blood vessels in the lining of the nasal cavities

• Mucus keeps air moist & keeps tissues from drying out

The Nose Continued• Mucus along with little hairs called

cilia trap tiny particles entering the nose

• These cilia also sweep old mucus towards the esophagus & down to the stomach where it is destroyed by hydrochloric acid

CILIA

LowerRespiratorySystem

• Larynx• Trachea • Bronchi• Bronchioles • Alveoli

The Anatomy of the Larynx

(voicebox)

Trachea(windpipe)

Bronchus Bronchus

bronchiolesbronchioles

alveoli alveoli

diaphragm

Diaphragm

Main muscle used in breathing

Diaphragm• Dome-shaped muscle at the bottom of the lungs.• When you breathe in, the diaphragm contracts

and flattens out while pulling downward. This movement enlarges the space that the lungs are in. This larger space pulls air into the lungs.

• When you breathe out, the diaphragm relaxes reducing the amount of space for the lungs and forcing air out.

• The diaphragm is the main muscle used in breathing.