what is the passageway for breathing
nasal cavity pharynx epiglottis larynx trachea bronchus bronchioles alveoli
what happens at the nasal cavity
the air is warmed and moistened
dust particles are removed air travels through the cavity
what happens at the larynx
air enters the larynx and passes over the vocal cords into the trachea
what happens at the trachea
it is surrounded by cartilage to maintain shape for airflow
what are the functions of the capillaries in regards to alveoli
-they make sure that oxygen from the air is transported to the working muscles so energy can be released for exercise
what is the thoracic cavity
- area inside the chest from the base of the neck to the diaphragm
- contains the heart and lungs and is protected by the ribs and sternum
- diaphragm and both intercostal muscles attach to the ribs
what is inspiration
-the thoracic cavity increases in size
-allowing the lungs to expand
-pressure within to drop compared to outside
AIR TO ENTER THE LUNGS
What is expiration
-thoracic cavity decreases in size reducing the size of the lungs
- pressure increases in the lungs compared to outside
AIR TO LEAVE THE LUNGS
what happens to your diaphragm and intercostal muscles when you breathe in
- during inspiration the diaphragm and external intercostal muscles CONTRACT
- increasing the area of the thoracic cavity
- diaphragm flattens as it contracts
- external intercostal muscles raise
- ribs and sternum rise to allow lungs to expand
what happens to your diaphragm and intercostal muscles when you breathe out
- diaphragm and external intercostal muscles relax
- internal intercostal muscles contract
- causes decrease in size of thoracic cavity and lungs
gas exchange in the alveoli
- oxygen concentration in alveoli is high but is low in blood
- oxygen leaves the area of high conc to area of low conc
- carbon dioxide levels are high in the blood
- CO2 leaves the blood and goes into the alveoli where conc is lower
what is pulmonary ventilation (VE)
- in order to exercise we need oxygen
- we get oxygen from the air we breathe
- respiratory system:
1. takes air into body
2. extracts some oxygen from it - process of moving air in and out of lungs is called pulmonary ventilation
what are the 4 types of lung volume
- tidal volume
- vital capacity
- residual volume
- total lung volume
what is tidal volume
the amount of air inspired or expired in a normal breath when a person is at rest.
what is vital capacity
the volume of air that can be inspired or expired per breath, including forced breathing
what is residual volume
the amount of air left in the lungs after forced breath (it cant be breathed out)
what is total lung volume
vital capacity and residual volume
where is the medulla oblongata found and what does it contain
in the brain stem and it contains nerve fibres
what is the medulla responsible for
- responsible for autonomic nervous activity
- is the respiratory centre transferring messages to and from the spinal cord to the brain
what do the messages sent by the medulla control
the messages control the action of the diaphragm and intercostal muscles, increasing the rate of breathing
what happens during exercise
chemoreceptors detect an increase in CO2 and a drop in pH due to exercise, the medulla then increases the breathing rate
what happens during recovery
chemoreceptors detect a drop in CO2 and an increase in pH during recovery, the medulla reduces breathing rate
what are the short term responses
- increase in breathing rate
- increase in tidal volume
what is the long term adaptations
- increased strength of the respiratory muscles
- increased vital capacity
- increase in oxygen and carbon dioxide diffusion rate
