Gas Exchange Flashcards
What factors can increase the rate of diffusion?
Short distance
Large concentration gradient
Large surface area:volume ratio
What is Fick’s law?
( Surface area x concentration difference ) / diffusion distance
What is the trachea?
A large tube covered partially in c-shaped cartilage rings, leading from the nasal and oral cavity, through the neck, to the bronchi.
What is the purpose of the cartilage on the trachea?
Prevents the trachea collapsing, changing shape, being cut off at certain angles, and damage when hit.
What are the bronchi?
2 Tubes that split off from the trachea, taking air throughout each Lung.
What are the alveoli?
Small air sacs covered in blood vessels (capillaries)
What adaptations do alveoli have to benefit gas exchange ?
Folded walls (increase SA:V)
Capillaries to take oxygenated blood away (increase the conc gradient)
Flattened epithelium walls with one cell thick capillaries (decreases diffusion distance)
What is the nasal and cavities?
Openings throughout the head to the respiratory system.
What do the nasal and oral cavity do to prevent respiratory illness?
Contains hairs to trap dust, and tissues to capture germs
What adaptations do the trachea and bronchi have ?
Warm/moist to prevent drying out Hairs to trap large dust particles Goblet cells to trap small particles Ciliated cells beat particles up the trachea to the throat to cough up Contain macrophages to fight bacteria
What other adaptations do the alveoli have ?
Moist inner surface - preventing drying out
Surfactant - prevents surface sticking
Macrophages
How do single celled organisms gain the oxygen they require for respiration?
diffusion across the cell membrane, as they have an extremely large surface area:volume ratio
what are spiracles?
Holes in the abdomen of insects, used to let air in and out of the tracheoles
what is the advantage of the insect in opening and closing the spiracles?
it conserves water when closed
What do humans do to move air in and out of the lungs?
Increase and decrease the pressure of the air inside their lungs, by contracting and relaxing their muscles to change the volume.
During inhalation, what happens to the volume, pressure and air?
Volume increases, decreasing pressure, and causing air to rush in from the atmosphere