Photosynthesis is the process by which plants convert light energy into chemical energy.

During photosynthesis, plants use sunlight, carbon dioxide, and water to produce glucose (sugar for energy) and oxygen.

This process happens in the chloroplasts of plant cells, specifically in structures called chlorophyll that give plants their green color.

Cellular respiration is the process cells use to release energy stored in glucose and convert it into ATP, the cell’s usable energy form.

During respiration, glucose reacts with oxygen to produce ATP, carbon dioxide, and water, fueling essential cellular activities.

This process mainly occurs in the mitochondria and happens in stages: glycolysis, the Krebs cycle, and the electron transport chain.

Enzymes are specialized proteins that speed up chemical reactions in cells without being used up, making life-sustaining processes occur fast enough.

Each enzyme is highly specific, binding only to certain substrates at its active site, like a key fitting a particular lock.

Factors such as temperature, pH, and substrate concentration can change enzyme shape and activity, sometimes stopping reactions entirely.

Membrane transport is how substances move in and out of cells across the plasma membrane, keeping internal conditions stable and balanced.

Some movement is passive, like diffusion and osmosis, which do not require energy and follow concentration gradients from high to low.