2. Punch biopsy Parasympathetic nervous system Noradrenaline NK cell activity Antigen Antibody

3. Punch biopsy – a small segment of skin is removed causing a bruise on the skin Parasympathetic nervous system – returns the animal to a state of relaxation Noradrenaline – a neurotransmitter, a substance released from the neuron activating (arousing) the organs to prepare for ‘fight or flight’ NK cell activity - is a major component of the innate immune system. NK cells play a major role in the rejection of tumors and cells infected by viruses Antigen – a foreign substance in the body, e.g. Virus Antibody – neutralises the effect of the antigen

4. Exam Question Outline and evaluate research into the link between stress and immune system functioning (8 marks) Outline research (4 marks) Evaluate research (4 marks) – Confounding variables, gender and age, Validity