5.3 Diffusion
First review @October 11, 2023
Practise Q's Done
movement of particles between areas of high concentration to low concentration
two types of diffusion, active and passive (both types require energy)
passive movement uses energy from the natural movement of particles
passive transport in the absence of a membrane is called simple diffusion
active transport uses energy from elsewhere to aid the movement of the particles from an
area of low concentration to an area of high concentration
Passive transport (diffusion)
net movement of particles from an area of high concentration of particles to an area of
low concentration of particles down a concentration gradient until there is no
concentration gradient
the movement is random and occurs when particles are moving and have kinetic energy
Factors affecting rate of diffusion
thickness of membrane
thickness of membrane and rate of diffusion are inversely proportional, as thickness
of membrane increases the rate of diffusion decreases, this is due to the distance of
diffusion increasing which leads to more frequent collisions of particles
concentration gradient
as the steepness of the concentration gradient increases the rate of diffusion increases
temperature
as the temperature increases the rate of diffusion also increases, this is due to the
increase in kinetic energy of the particles and therefore equilibria is reached more
quickly
surface area
5.3 Diffusion 1
First review @October 11, 2023
Practise Q's Done
movement of particles between areas of high concentration to low concentration
two types of diffusion, active and passive (both types require energy)
passive movement uses energy from the natural movement of particles
passive transport in the absence of a membrane is called simple diffusion
active transport uses energy from elsewhere to aid the movement of the particles from an
area of low concentration to an area of high concentration
Passive transport (diffusion)
net movement of particles from an area of high concentration of particles to an area of
low concentration of particles down a concentration gradient until there is no
concentration gradient
the movement is random and occurs when particles are moving and have kinetic energy
Factors affecting rate of diffusion
thickness of membrane
thickness of membrane and rate of diffusion are inversely proportional, as thickness
of membrane increases the rate of diffusion decreases, this is due to the distance of
diffusion increasing which leads to more frequent collisions of particles
concentration gradient
as the steepness of the concentration gradient increases the rate of diffusion increases
temperature
as the temperature increases the rate of diffusion also increases, this is due to the
increase in kinetic energy of the particles and therefore equilibria is reached more
quickly
surface area
5.3 Diffusion 1
