Biology Paper 1 Organisation (17 Videos) The Digestive System Digestive Enzymes Effect of Temperature and pH on Enzymes Required Practical 4: Food Tests Required Practical 5: Effect of pH on Amylase Absorption in the Small Intestine The Heart and Circulation Arteries, Veins and Capillaries The Blood Cardiovascular Diseases Gas Exchange in the Lungs Cancer Communicable and Non-Communicable Disease Correlating Risk Factors Lifestyle and Disease Plant tissues Transpiration Back Workbooks