What is diffusion in scientific terms?

Diffusion is scientifically defined as the spontaneous movement of molecules from an area of high concentration to an area of low concentration. This process occurs due to the random motion of molecules and continues until there is an equilibrium, where the concentration is uniform throughout the space.

In biological contexts, diffusion is crucial for processes such as gas exchange in lungs, nutrient uptake in cells, and the movement of waste products. It is a passive transport mechanism, meaning it does not require energy input from the cell, and it is driven purely by the concentration gradient. This principle is central to many physiological functions, making it a fundamental concept in biology.

Understanding diffusion helps elucidate how substances interact within biological systems and the importance of concentration gradients in maintaining cellular homeostasis.