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 covering Edexcel IGCSE Biology Biological molecules for IGCSE Biology. Each lesson works through exam-style questions in Paper 1 and Paper 2 format. 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.