Respiratory system-anatomy

• >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.

> 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

Upper respiratory system (URTI)

• >Nose
• >Nasal cavity
• >Sinuses
• >Pharynx

• Lower respiratory sytem (LRTI)
• >Larynx
• >Trachea
• >Bronchi 
• >Lungs
• >Alveoli

Gas exchange occurs here

• >bronchoiles
• >alvelor
• >ducts
• >alveorlar sacs & alveoli

The passageway where air travels

• >Nose
• >nasal cavity
• >sinuses
• >Pharynx
• >Larynx
• >trachea
• >bronchi
• >Lungs

• >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

> 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