Name four substances an organism needs to exchange with its environment.
Carbon Dioxide
Oxygen
Glucose
Urea
Nitrogen
Select two features of alveoli that makes them suitable for efficient gaseous exchange.
Large Surface Area
Good Blood Supply
Small Surface Area
Thick Cells
The trachea contains ciliated epithelium.
The goblet cells secrete haemoglobin to trap microorganisms.
Cilia on the surface of cells waft the mucus to move it to the top of the airway to be swallowed.
Elastic fibres allow the airway diameter to be controlled.
Which of these DO the alveoli contain.
Smooth Muscle
Goblet Cells
Elastic Fibres
Cilia
The cartilage provides support.
During inspiration, the intercostal muscles contract, causing the ribcage to move upwards and outwards and the diaphragm to flatten, increasing the volume of the thorax and decreasing lung pressure.
Expiration is an active process - it requires energy.
Tidal volume is the volume of air in each breath.
Vital capacity is the maximum amount of air that can be breathed in or out.
Breathing rate is how many breaths are taken - usually in a minute.
Oxygen intake is the rate at which a person uses up oxygen e.g. number of dm3 used per minute.
Soda lime in a spirometer absorbs the oxygen.
