Question

The relationship between concentration difference across a membrane and the rate of diffusion

Answer 1

The difference in the concentration of a substance between two areas is called the concentration gradient . The bigger the difference, the steeper the concentration gradient and the faster the molecules of a substance will diffuse. The direction of diffusion is said to be 'down' or 'with' the concentration gradient. The concentration gradient therefore represents the concept that, just as a ball rolls down a slope, during diffusion molecules move down the concentration gradient. Higher concentration gradients will result in higher rates of diffusion. As the molecules move the gradient evens out until equilibrium is reached.

Answer 2

Answer:

• The rate of diffusion is affected by the concentration gradient, membrane permeability, temperature, and pressure. Diffusion takes place as long as there is a difference between the concentrations of a substance across a barrier.

• The concentration gradient therefore represents the concept that, just as a ball rolls down a slope, during diffusion molecules move down the concentration gradient. Higher concentration gradients will result in higher rates of diffusion. As the molecules move the gradient evens out until equilibrium is reached.