Part IV: Pupillary Reflex 8. Have the subject close one eye for approximately 1 min . Ask him or her to open the closed eye. Compare the size of the pupils.
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Which pupil is larger? 9. Ask the subject to close both eyes for one min, then open both eyes. Shine a penlight in 1 of the eyes. /1 (h) Describe the changes you observe in the pupil. 10. Select a student with light-coloured eyes to be the subject. With at least two observers carefully watching the subject's eyes, gently stroke the fine hairs on the nape of the subject's neck. /1 (i) Describe any change in the pupils of the subject. Analysis /4 (j) From your observations, formulate a hypothesis about the sequence of events that occur in the nervous system in each part of the procedure. 13 (k) How does the knee-jerk reflex change when the subject is clenching the book? Why do you think this is? 13 (I) What is the purpose of testing different reflexes? Evaluation and Synthesis /3(m) Explain why the knee-jerk and Achilles reflexes are important in walking.
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(n) A person touches a stove, withdraws his or her hand, and then yells. Why does the yelling occur after the hand is withdrawn? Does the person become aware of the pain before the hand is withdrawn? /3 (o) While examining the victim of a serious car accident, a physician lightly pokes the patient's leg with a needle. The pokes begin near the ankle and gradually progress toward the knee. Why is the physician poking the patient? Why begin near the foot? NEL