Biology A H020: Biological membranes Topical Past Paper Questions

(a) The graph shows the rate of uptake of particles across a membrane by two different methods of diffusion. (b) Temperature and concentration are two factors that affect the rate of diffusion. State one other factor that affects the rate of diffusion. (c) Students used a model c…

Cell surface membranes are composed of many different components, including cholesterol. (a) Describe two roles of a cell surface membrane. 1 ..... 2 ..... [2] (b) The presence of cholesterol is one of several factors that affect membrane fluidity. A student examined two differen…

Fig. 22 shows a triglyceride molecule found in sunflower oil. Fig. 22 (a) On Fig. 22 circle an ester bond. [Answer on Fig. 22] (b) Sunflower oil is used to make biodiesel, which contains methyl esters. The fatty acids in the triglyceride molecule are reacted with methanol in a pr…