Enzymes and Molecular Movement

Enzymes are protein molecules that act as biological catalysts, speeding up chemical reactions in living organisms. They have a specific three-dimensional shape that allows them to bind with specific substrates and lower the activation energy required for the reaction to occur.

pH and temperature can affect the shape and function of enzymes. Extreme pH levels or temperatures can denature enzymes, altering their shape and rendering them ineffective. Each enzyme has an optimal pH and temperature at which it functions most efficiently.

Diffusion is the passive movement of molecules from an area of high concentration to an area of low concentration. Osmosis is the diffusion of water molecules across a selectively permeable membrane. Active transport is the movement of molecules against the concentration gradient, requiring energy in the form of ATP. While diffusion and osmosis are passive processes, active transport is an energy-requiring process.