Cells, enzymes, transport - Co-ordinated Sciences IGCSE Study Notes

Cells are the basic units of life, providing structure and function to all living organisms. Each cell has specialized components, including the nucleus, cytoplasm, and cell membrane, which work together to maintain cellular homeostasis. Enzymes are biological catalysts that speed up chemical reactions in the body by lowering the activation energy. They are essential for metabolic processes and are highly specific to substrates. Transport mechanisms allow substances to move into and out of cells, ensuring that cells receive necessary nutrients while eliminating waste. Understanding how these components interact is vital for grasping more complex biological processes.

Understanding the fundamental concepts related to cells, enzymes, and transport is necessary for IGCSE students. A cell is defined as the smallest unit of life that can replicate independently. Enzymes are proteins that act as catalysts to facilitate biochemical reactions. The cell membrane is a selective barrier that regulates the entry and exit of substances, employing transport mechanisms such as diffusion, osmosis, and active transport. The structure-function relationship in cells means that specific organelles (like mitochondria and ribosomes) have unique roles. The factors influencing enzyme activity include temperature, pH, and substrate concentration. Together, these concepts form a cohesive picture of how cells function and communicate in a biological system.