Respiratory System
Function
• Brings oxygen from the air into the body and
expels carbon dioxide from the body
▫ Accomplished by circulatory system
Upper Respiratory System
• Consists of the nose, mouth, pharynx, epiglottis,
and larynx
▫ Mucous membranes
 Lining of respiratory tract that secrete mucus
▫ Mucus
 Slimy secretion that helps to warm, moisten, and
filter air
Upper Respiratory System
• Cilia
▫ Tiny wave-like hairs that line the nostrils and help to
filter air
• Pharynx
▫ Passageway shared by the digestive and respiratory
system
• Epiglottis
▫ Tiny flap that covers the larynx during swallowing
• Larynx
▫ “voice box,” contains vocal cords that vibrate when air
passes through
5
Nasal cavity
Anatomy &
Physiology
TM
Pharynx
Esophagus
Mouth
Larynx
Epiglottis
Tongue
Trachea
Lower Respiratory System
• Trachea
▫ “windpipe,” has rings of cartilage that keep its shape.
• Bronchi
▫ Branches at the bottom of the trachea that are
contained in the lungs. (singular: bronchus)
• Bronchial tree
▫ Term describing how branches of the bronchi get
continually smaller, like a tree branch
• Bronchioles
▫ Small branches of the bronchial tree
Lower Respiratory System
• Alveoli
▫ Grape-like clusters at ends of bronchioles where
exchange of gases occurs
• Lungs
▫ Paired organs containing bronchi that are divided into
clearly defined lobes
• Diaphragm
▫ Muscle located below the lungs that contracts causing
the lungs to fill with air.
8
Epiglottis
Larynx
Anatomy &
Physiology
TM
Alveoli
Trachea
Cartilage
ring
Lungs
Bronchi
Bronchioles
Breathing
• Inhalation
▫ Drawing in of a breath
• Exhalation
▫ Release of a breath
• Apnea
▫ Not breathing
Breathing
• Dyspnea
▫ Difficult breathing
• Bradypnea
▫ Abnormally slow breathing rate
• Tachypnea
▫ Abnormally fast breathing rate
• Respiration
▫ Exchange of oxygen and carbon dioxide gases in the
lungs