B3 OCR GCSE

This document provides revision notes on biology topics related to living and growing. It covers: [1] the basic components of cells and their functions; [2] DNA structure and replication; [3] enzymes and diffusion; [4] the cardiovascular system including blood, blood vessels, and the heart; [5] cell division; [6] human growth and development; and [7] plant growth and responses to stimuli like light and gravity. The notes define key terms and concepts in a concise yet detailed manner.