Biology Flashcards
Definition of concentration gradient
an imaginary ‘slope’ from a high concentration to a low concentration.
Definition of osmosis(1)
the diffusion of water molecules through a partially permeable membrane.
Definition of diffusion
the net movement of particles from a region of their higher concentration to a region of their lower concentration(i.e.down a concentration gradient), as a result of their random movement.
Definition of osmosis(2)
(in terms of water potential)the net movement of water molecules from a region of higher water potential(dilute solution) to a region of lower water potential(concentrated solution) through a partially permeable membrane.
Definition of net movement
overall or average movement.
Definition of particles
(in this context) the smallest pieces of which a substance is made; particles can be molecules, atoms or ions.
Definition of compound
a substance formed by the chemical combination of two or more elements infixed proportions.
Definition of partially permeable membrane
a membrane (very thin layer) that lets some particles move through it, but prevents others passing through.
Definition of high water potential
an area where there are a lot of water molecules -a dilute solution.
Definition of low water potential
an area where there are not many water molecules -a concentrated solution.
Definition of water potential gradient
a difference in water potential between two areas.
