Text Book Exam Style Questions

Question 1

What is meant by homeostasis

Answer 1

Maintaining a constant INTERNAL ENVIRONMENT

Question 2

Describe the process involved in thermoregulation in response to large decrease in external temperature

Answer 2

Hypothalamus
Has receptors which detect temperature change in blood

Receives impulses from receptors in skin

Hypothalamus transmit nerve impulses

Question 3

Explain 3 advantages of endothermy over ectothermy

Answer 3

Enzymes at optimum temperature

Metabolic reactions proceed more quickly

More independent of environment

Question 4

Describe the role of insulin in the control of blood glucose concentration

Answer 4

Insulin secreted when increase in blood sugar

Insulin binds to receptors on cells

Leads to more glucose entering cells

Question 5

When dead cross bridges between actin and myosin remain firmly bound. Explain why

Answer 5

Respiration stops
No ATP produced
ATP required to separate actin and myosin cross bridges

Question 6

Describe the role of ATP and phophocreatine in producing contraction of a muscle fibre

Answer 6

ATP allow myosin to detach from actin

Phophocreatine allows regeneration of ATP

Under anaerobic conditions

Phophocreatine releases Pi to join ADP