List two mechanisms that the body uses in response to an infection.

Discuss the relationship shown in the following graph.

[Source: Roy Stevenson.]

the skin / epithelial linings ✔

mucus ✔

enzymes ✔

macrophages ✔

platelets ✔

phagocytes/leucocytes✔

pH of bodily fluids ✔

hormones ✔

soluble factors e.g. cytokines ✔

lymphocytes/antibodies ✔

inflammation ✔

moderate volume of exercise appears to decrease the risk of infections compared to not exercising ✔

very high volume of exercise increases the risk higher than not exercising at all ✔

high risk of infection at high volume of exercise can be caused by increased depth and rate of breathing during intense training/lowered leucocyte levels/inflammation ✔

Award [1 max] for a list.

Generally answered well.

Poorly answered, most candidates simply described the three volumes of training and the impact on risk of upper respiratory tract infection. Very few candidates were able to discuss the relationship. Most candidates only achieved 1 mark.