Respiratory system Flashcards
What are the two main functions of the respiratory system?
- pulmonary ventilation: inspiration and expiration
- gaseous exchange (external and internal)
What is external respiration?
movement of oxygen into the blood system and carbon dioxide into the lungs
What is internal respiration?
the release of oxygen to respiring cells for energy production and collection of waste products
Explain the path of air through the body?
- air is drawn into nasal cavity through the nose and travels down pharynx, larynx and trachea.
- trachea divides into left and right bronchi as they enter lung cavity
- bronchi sub divide into smaller bronchioles and end in alveolar ducts
- air moves into alveoli by diffusion
In what two ways can oxygen be transported
- carried with heamoglobin in red blood cless
- carried within blood plasma
What is carbon dioxide a waste product of?
aerobic energy production
What three ways can carbon dioxide be transported>
- dissolved in water and carried as carbonic acid
- carried with haemoglobin
- dissolved in blood plasma
What is breathing rate?
- number of inspirations per minute
What is tidal volume?
volume of air inspired or expired per breath
What is minute ventilation?
-volume of air inspired or expired per minute
How do you calculate minute ventilation?
tidal volume x breathing rate
Explain minute ventilation response to increasing exercise intensity?
- initial anticipatory rise in VE prior to excersie due to release of adrenaline
- rapid increase in VE at start of excersise due to increased f and TV in order to increase oxygen delivery and waster removal
- steady state VE throughout the sustained intensity exercise as oxygen supply meets demand
- initially rapid and then more gradual decrease in VE to resting levels as recovary is entered and the demand for oxygen reduces
Where are the lungs located and what are they encased in?
- located in thoracic cavity and encased in pleural sacs
What reduces friction between inspiration and expiration?
pleural fluid between lung and pleural membrane
Which two muscles are responsible for inspiration at rest?
- external intercostals (contract lifting rib cage and sternum up and out)
- diaphragm (seperates the thoracic and abdominal cavity, contracts and flattens)
Explain the pressure differance in the lungs at rest?
- volume inside thoracic cavity and space inside lungs lungs increases. lowers the pressure below the atmosphere outside body. gases move from high to low pressure, so air rushes into the lungs