- >Function is to transport O2 around the body
- >oxygen is carried in blood via circulatory system
- >CO2 leave the tissues cells as waste taken to lungs to be excreted
- > Blood maintain homeostasis by regulating blood Ph as coz is excreted.
- >overall function of RS is gas exchange, others include warming, pruifying, humidifying the air as it travels thru the passages.
- >Ensures air in lungs is warm, damp & less irritants
- >Structurally divided into 2 compartment
>RS collects O2 from the capillaries in lungs and excretes CO2 from capillaries in blood -via breathing
>cardiovascular system transports O2 to body's tissues/cells and myocardium picks up CO2 and transport it to lungs for excretion.
>CVS uses blood as carrier of gases transporting to lungs.
Process of gas exchange
> gas exchange occurs via diffusion as O2/CO2 are moved between the blood & lungs.
consists of pulmonary circulation and systemic circulation
Breathing in process
- >Pulmonary circulation leaves teh heart O2 poor
- >travel to the lungs
- >O2 diffuses across lungs to blood and CO2 leaves the blood and enter the lungs
- >Blood returns to the heart rich in O2
- >SC leaves he heart O2 rich
- >travels to the tissues/cells
- >O2 diffuses across to the cells & CO2 leaves the tissues and enters blood.
- >blood returns to the heart as O2 poor
Stucture of respiratory system
Upper respiratory system (URTI)
- >Nasal cavity
- Lower respiratory sytem (LRTI)
Gas exchange occurs here
- >alveorlar sacs & alveoli
The passageway where air travels
- >nasal cavity
Nose - nasal cavity
- >divided by nasal septum
- >surrounded by sinuses that assist with speech sounds, produce mucous which drains into nasal cavity
- >air enter nasal cavity via nostrils
- >Olfactory receptors located in nasal function is to provide a sense of smell
- >Muscosa rests on a thin wall of veins, function is to warm the air as it passes
- >Muscous, acts as deterent to pathogens, trapping invading foreign debri.
- >Debri destroyed by enzymes found in mucous.
- >Cilia prevent contaminated mucous entering lungs
- >Palate separates nose from oral cavity
Pharynx - throat
> continuous muscular organ responsible for movement of food & fluid.
- > channels for food and air.
- >Epiglottis is an elastin cartilage that ensures food/ liquids traves into the oeshagus instead of to the lungs.
- >consists of rings of hyaline cartilage
- >Rings support the walls of trachea, keeping it open during time of exertion/rapid breathing
- >ring also assists oeshagus to expand during swallowing of large pieces of food.
- >line with cilia
- >Trachea divides R & L bronchi
- >Break into smaller subdivisions to the aveoli
- >R brochus is wide, shorter, straighter
- >R brochus is more likely to incur foreign body.
- >R lung has 3 lobes
- >L lung has 2 lobe
- >Brochi enter lung and divide into samller branches ending with brochoiles. (respiratory tree)
- >The ability to expand and recoil as air oves in/out is dependent upon elastic tissue
- > each lung is covered in a membrane called visceral pluera
- >Wall of thoracic cavity is covered in parietal pleura
- > both membrane produce slippery, viscous secretion that aids the movement ot the lungs without causing any fraction
- >may become inflammed causing pain and difficulty breathing ( pluerisy).
> the ability of lungs to relax and expand freely is dependent upon the presence of pleural fluid
- >thin walls
- >enables air to move through them
- >surface is coated in water like liquid, moist
- >Expand during inhaling inresponse to incoming air
- >Recoil back to orginal size during exhaling
- >Surface of alveoli are pulmonary capillaries
- >Pulmonary capillaries and alveoli combine to form the respiratory membrane
- >Allowing O2 to diffuse from alveoli to capillaries and Co2 to diffuse from capillaries to alveoli
- >alveoli defend against pathogen
- > produce surfactant