Dissolved Substances Flashcards
define osmosis
osmosis is the movement of water from an area of low concentration to one of high concentration through a semi permeable membrane
what do most soft drinks contain?(3)
water, sugar and ions
why are water and ions included?
to replace those lost in sweat
definition of active transport?
substances absorbed against a concentration gradient
what things improve effectiveness of material exchange
having a large SA, Being thin to provide a short diffusion path, (animals) have efficient blood supply, (animals/gases) being ventilated
in humans what two things increase effectiveness of diffusion/ osmosis/ active transport
the SA of the lungs increased by alveoli
the SA of the small intestine increased by villi
three ways in which substances can be transferred around a plant
osmosis, diffusion, active transport
