Elements and building blocks
Elements and building blocks
Living organisms contain biological molecules such as carbohydrates, proteins and lipids. A chemical element is a pure substance made from one type of atom, such as carbon or oxygen.
Step-by-step lessons on Edexcel IGCSE Biology Biological molecules. Each one builds up to exam-style questions. Start with the foundational cell biology and core content before moving on to the more data-heavy ecology, genetics and practical-skills topics, which carry a large share of the exam marks.