Water, carbohydrates and lipidsEdexcel A-Level Biology A: Mind map

Exam questions on Water, carbohydrates and lipids

1. Blood plasma in a mammal is mostly water. It carries dissolved glucose, amino acids and mineral ions around the body between the gut, the liver and the tissues.
   Explain why an ionic compound such as sodium chloride dissolves in water.2 marks
2. Glycogen is stored in the liver and muscle cells of mammals. Starch is stored in the tubers of potato plants. Both are made by joining sugar molecules together.
   Describe how maltose is broken down into glucose.2 marks
3. A marathon runner stores glycogen in her muscles and liver and relies on it during the race. A potato plant stores starch in its tubers over winter. Both stores are made from the same monomer.
   Explain how the structure of glycogen makes it suitable as an energy store in the runner's muscles.3 marks