1. 1
   A paramedic explains to trainee students that when a person stands up suddenly after lying down, receptors detect the drop in blood pressure and the body automatically adjusts heart rate and blood vessel width within a few seconds, without the person having to think about it.

   (a)

   Which term describes this automatic regulation of internal conditions to maintain a stable internal environment?

   [1 mark]

   • AHomeostasis
   • BMetabolism
   • CDigestion
   • DRespiration

   (b)

   In this control system, what is the role of the part of the body that receives information about the drop in blood pressure and directs the response?

   [1 mark]

   • AReceptor
   • BEffector
   • CHormone
   • DCoordination centre

   (c)

   Name the three main components of a control system in the body, other than the stimulus itself, and state the general function of each.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A swimmer steps barefoot onto a sharp shell hidden in the sand and immediately pulls her foot away, before she consciously feels any pain.

   (a)

   Which sequence correctly describes the pathway of information in this reflex action?

   [1 mark]

   • AEffector → coordinator → receptor → response
   • BStimulus → receptor → coordinator → effector → response
   • CStimulus → effector → receptor → response
   • DResponse → stimulus → receptor → effector

   (b)

   Which neurone in the reflex arc carries the impulse directly from the spinal cord to the muscle that pulls the foot away?

   [1 mark]

   • ASensory neurone
   • BRelay neurone
   • CMotor neurone
   • DReceptor neurone

   (c)

   Explain why it is an advantage that this reflex action does not involve the conscious part of the brain.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A driver narrowly avoids a collision at a busy junction. In the moments afterwards, she notices her heart pounding and feels a surge of energy, even though there is no more danger.

   (a)

   Compare how hormonal communication in the body differs from nervous communication in terms of the speed and duration of the response.

   [3 marks]

   (b)

   Explain how the release of adrenaline into the driver's blood after the near miss prepares her body for 'fight or flight'.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A hospital phlebotomist takes a unit of blood (about 470 cm³) from a healthy volunteer at a blood donation session. Immediately afterwards, the volume of blood plasma in the donor's body is slightly reduced.

   (a)

   Describe how the kidneys produce urine from the blood, and explain how this process would remove waste products from the donor's blood in the hours after donating.

   [6 marks]

   (b)

   Explain, using the idea of negative feedback, how the donor's body responds to the slightly reduced blood plasma volume after donating blood.

   [6 marks]

   Total for question 4: 12 marks

5. 5
   A nurse working a night shift skips her evening meal because the ward is busy. By midnight she begins to feel shaky and finds it hard to concentrate, so she eats a cereal bar from her bag.

   (a)

   Which hormone was mainly responsible for raising the nurse's blood glucose concentration back towards normal before she ate the cereal bar?

   [1 mark]

   • AInsulin
   • BAdrenaline
   • COestrogen
   • DGlucagon

   (b)

   After eating the cereal bar, the nurse's blood glucose concentration rises. In which organ is much of the excess glucose converted to glycogen for storage?

   [1 mark]

   • ALiver
   • BKidney
   • CPancreas
   • DPituitary gland

   (c)

   Explain how insulin brings the nurse's blood glucose concentration back down to normal after eating the cereal bar.

   [2 marks]

   Total for question 5: 4 marks

6. 6
   A librarian is shelving books in a poorly heated store room on a cold winter morning. After a few minutes she notices her skin has become pale, she has goosebumps, and she starts to shiver.

   (a)

   Which term describes the narrowing of blood vessels supplying the skin, which contributes to the pale appearance of the librarian's skin in the cold?

   [1 mark]

   • AVasodilation
   • BSweating
   • CVasoconstriction
   • DShivering

   (b)

   Which structure monitors the librarian's blood temperature and coordinates the responses that keep her body temperature constant?

   [1 mark]

   • AThe pancreas
   • BThe thermoregulatory centre in the brain
   • CThe pituitary gland
   • DThe spinal cord

   (c)

   Explain how shivering helps to raise the librarian's body temperature back towards normal.

   [2 marks]

   Total for question 6: 4 marks

7. 7
   A school nurse is preparing a talk for a Year 8 class about the hormonal changes that happen during puberty and the menstrual cycle.

   (a)

   Describe the roles of oestrogen and testosterone in the development of secondary sexual characteristics at puberty.

   [3 marks]

   (b)

   Explain the roles of FSH, LH, oestrogen and progesterone in controlling the menstrual cycle.

   [4 marks]

   Total for question 7: 7 marks

8. 8
   A horticulturist is trialling a rooting powder made from a plant hormone to help cuttings taken from a rare, slow-growing shrub develop roots more quickly. The cuttings are kept on a windowsill, where light reaches them mainly from one side.

   (a)

   Explain why the shoots of the cuttings on the windowsill grow bent towards the light, and how this response is coordinated by a plant hormone.

   [6 marks]

   (b)

   Evaluate why using rooting powder containing a plant hormone is a useful method for the horticulturist to propagate this rare shrub, compared with waiting for cuttings to root naturally.

   [6 marks]

   Total for question 8: 12 marks

End of questions