For an organism to function, substances must move into and out of cells. Three processes contribute to this movement – diffusion, osmosis and active transport.
What is the definition of diffusion?
The movement of molecules from an area of high concentration to an area of low concentration
The movement of water from an area of high concentration to an area of low concentration
The movement of molecules from an area of low concentration to an area of high concentration
What term is used to describe the membrane across which particles move into or out of the cell?
Which of these will increase the rate of diffusion?
A decrease in temperature
An increase in the concentration gradient
A smaller surface area
What happens to the surface area: volume ratio as the size of an organism increases?
It stays the same
What would happen if a red blood cell was placed in pure water?
It would become turgid
It would burst
It would become flaccid
What would happen to an animal cell if it was placed in a concentrated salt solution?
It becomes turgid
It stays the same size
It becomes flaccid
Which term can be used to describe both osmosis and diffusion?
Against a concentration gradient
Specific to water
What substance is required by a cell so that it can carry out active transport?
What chemical is released during aerobic respiration that provides the energy needed for active transport?
Mineral ions are transported into a root hair cell against a concentration gradient by which method?