Diffusion

Diffusion / Factors / Adaptations in body

Diffusion

The process of particles moving from an area of higher concentration to an area of lower concentration in a solution or gas.

Factors affecting diffusion rate

Includes concentration gradient, temperature, and surface area of the membrane.

Single-celled organism

Organism with a high surface area to volume ratio for efficient molecule transport.

Multicellular organisms

Have a low surface area to volume ratio and have specialized surfaces and organ systems for material exchange to meet the organism's needs.

Characteristics of effective exchange surfaces

Large surface area, thin membrane, efficient blood supply (in animals), and ventilation (in animals for gaseous exchange).