B4.3 How do living organisms obtain energy? All living organisms require energy released by respiration for some chemical reaction in cells – the energy is used for: Movement Synthesising (making) larger molecules Active transport Large molecules, such as starch and...
B4.2 How do plants make food? Photosynthesis can be written as There are three main stages in photosynthesis: ❶ Light energy is absorbed by the green chlorophyll ❷ Energy used to bring about the reaction between carbon dioxide and water to produce glucose (a...
B4.1 How do chemicals reactions take place in living things All living cells are made from basic units – these are called CELLS. The processes of life carried out by all living cells depend on chemical reactions within cells – these reactions need energy released by...