1. Which of the following statements regarding a nervous response is true ?
a) Communication in the nervus response is via electrical signals only.
b) Impulses in the nervous response is transmitted by nerve cells.
c) It usually takes a long time before the effector responds to a stimulus during a nervous response.
d) Nervous responses usually affect more than one target organ.
Answer
b) Impulses in the nervous response is transmitted by nerve cells.
2. What are the common names of the eye defects myopia and hyperopia ?
Answer
Myopia - short sightedness, and hyperopia - long sightedness.
3. State the two main functions of the nervous system.
a) To react to surroundings (external stimuli) and to coordinate behaviour
b) To pump blood and regulate breathing
c) To digest food and absorb nutrients
d) To filter waste and maintain water balance
Answer
a) To react to surroundings (or external) stimuli and to coordinate behaviour
4. Explain what a synapse is.
a) A sensory receptor that detects external stimuli
b) A protective sheath surrounding an axon
c) A chemical messenger released into the bloodstream
d) A junction (or gap) between two neurones.
Answer
d) A junction (or gap) between two neurones
5. The students use a computer program to test their reaction times. They have to click a button when they see a red stop sign. Suggest two reasons why measuring reaction times with a computer will provide more valid results than the classic methods used.
Answer
The computer will give a more precise reaction time and the students will not be able to tell when the stop sign is about to appear.
6. Why is investigating and treating brain disorders very difficult?
a) Because the brain is protected by the skull and blood–brain barrier, limiting access to treatments
b) Because the brain is very complex and very delicate
c) Because the brain has no blood supply and cannot receive nutrients
d) Because the brain is made only of muscles and connective tissue
Answer
b) Because the brain is very complex and very delicate
7. Give the function of the sclera.
a) To protect the eye and provide structural support
b) To focus light onto the retina
c) To regulate the amount of light entering the eye
d) To transmit visual information to the brain
Answer
a) To protect the eye and provide structural support
8. Some people with myopia do not want to wear spectacles. Suggest two alternatives to wearing spectacles.
Answer
Hard or soft contact lenses, or laser surgery, can be used to change the shape of the cornea.
9. When a person's body temperature falls, they may begin to shiver. Explain how shivering can increase body temperature.
Answer
Muscles contract and relax rapidly, increasing the rate of respiration and releasing more heat energy.