breathing system

breathing

taking in oxygen from the atmosphere and releasing carbon dioxide

Homeostasis

maintenance of a stable internal environment

Lungs

-are air tight

-located in thoracic cavity

-protected by rib cage and sternum

nasal passage

lined with cilia and mucus to trap dust particles and pollem

Epiglottis

flap of tissue at the top of trachea to seal during eating and prevents food from entering

Pharynx

creates a passage for air to travel

larynx

creates sound/voice

trachea

allows air to enter lungs longer with rings of cartilage to prevent collapse

bronchus

trachea divides into two bronchus

one leading into each lung

Bronchioles

bronchus divides into smaller branches

alveoli

site of gas exchange at the end of the bronchioles

Alveoli adaptations

-presence of many alveoli (large surface area)

-walls are one cell thick

-moist surface

-surrounded by a good blood supply

intercostal muscles

move the ribs by contracting

ribs

Protect the lungs

Diaphragm

contracts and expands lungs

Gaseous exchange in alveoli

Oxygen moves through walls of alveoli and into capillaries into red blood cells. Carbon dioxide in blood moves through walls of capillaries into alveoli

asthma symptoms

coughing and difficulty breathing

asthma cause

presence of dust, pollen and other allergens

asthma treatment and prevention

inhaler