Respiratory System Flashcards
What are the functions of the lungs?
- Ventilation
- O2 intake and CO2 output
- Water loss
- Heat removal
Function of the upper airway?
- Provide passage for air to pass to body
- Warm and moisten air prior to entering lungs
- Filter out particles, via cilia, coughing or swallowing
- Directs, air, fluid and food to the correct organs
Functions of Trachea
Rigid walls made of hyaline cartilage
Lined with ciliates mucosa to expel foreign bodies
5 Facts about the lungs?
Base rests on diaphragm
Each lung is divided into lobes by fissures
Left has 2 lobes right has 3 lobes
Covered by a lining called visceral pleura
Contain pleural fluid allowing lungs to glide over the thorax wall
What are bronchioles?
Primary Bronchi is sub divided not bronchioles
They terminate at the alveoli (air sacs)
The terminal bronchioles lead to respiratory zone structures
What are alveoli composed of?
A single layer of squamous epithelial cells
‘What is the air blood barrier’ ?
Alveoli are covered in cobwebs of pulmonary capillaries
Air is flowing past one side and blood flowing passed the other
Gas’s exchange occurs by simple diffusion through the respiratory membrane
Area for gas exchange is approx 40x greater then the surface of the skin
What happens to your resp rate when you are acidotic ?
Your resp rate increases
Associated structures with the respiratory system?
Chemoreceptors for O2 and CO2
Afferent nerve to the brain from :- intercostal muscles and diaphragm
Medulla oblongata
Efferent nerve to the :- rib cage, intercostal muscles and diaphragm
What happens during inspiration?
- Diaphragm and external intercostal muscles contract
- Dome shaped diaphragm contracts + flattens increasing the height of the thorax cavity
- Contraction of the external intercostal muscles lift the rib cage up and sternum forward, increasing the anterior - posterior dimension of the thorax
What happens during expiration?
Inspiratory muscles relax, rib cage descends and lungs re coil
- Gases flow out
Chemical control of the respiratory system?
- Blood gas’s composition monitored by chemoreceptors, that respond to changes in CO2 and O2
- Chemoreceptors are found in the carotid body and aortic body (peripheral receptors)
- Changes in CO2 levels trigger impulses to the respiratory centre of their brain.
- This triggers phrenic and intercostal nerves and increases the rate in order to lower CO2
What are the three volumes of the lungs?
Tidal volume = 500 mls (air moved into and out of the lungs with each breath)
Residual volume= 1200mls ( air left in lungs after expiration)
Dead space volume= 150mls (air that remains in the conducting zone)
Altered physiology
What happens when the CO2 and lactic acid level rise?
High levels of CO2 can cause the lactic acid levels to rise (the blood pH falls making it more acidic)
- Chemoreceptors in the carotid body detect the rise in CO2 and Lactic acid
- This stimulates the respiratory centre in the Medulla oblongata
- Diaphragm and intercostal muscles respond
- The resp rate increases
- The excretion of of CO2 causes the blood pH to back to neutral 7.35-7.45
Signs and symptoms of respiratory distress
- Tachypnoea (rapid breathing)
- Use of accessory muscles
- Cyanosis
- Air hunger