Quiz Chapter 12: Coordination and Response in Humans

1. A patient suffers a head injury and loses the ability to speak clearly and make logical decisions, though their balance remains intact. Which brain region was damaged?

1. A. Cerebellum
2. B. Medulla oblongata
3. C. Hypothalamus
4. D. Cerebrum

2. Which structure in the brain is primarily responsible for maintaining posture, balance, and motor coordination?

1. A. Cerebrum
2. B. Medulla oblongata
3. C. Cerebellum
4. D. Hypothalamus

3. What role does the myelin sheath play in a neurone?

1. A. It synthesizes neurotransmitters for the synapse.
2. B. It protects the cell body from physical damage.
3. C. It insulates the axon and accelerates impulse transmission speed.
4. D. It receives incoming stimuli directly from sensory receptors.

4. How do chemical signals cross the synaptic gap if electrical impulses cannot jump across it?

1. A. Via active transport of sodium ions across air gaps
2. B. Via diffusion of neurotransmitters across the synaptic cleft
3. C. Via direct physical contact of axon terminals during contraction
4. D. Via osmotic pressure flow of cerebrospinal fluid

5. What distinguishes voluntary actions from involuntary actions?

1. A. Voluntary actions always bypass the brain.
2. B. Voluntary actions involve conscious control by the cerebral cortex.
3. C. Involuntary actions are executed slower than voluntary actions.
4. D. Involuntary actions do not require effector organs.

6. What structural feature of sensory neurones differentiates them from motor neurones?

1. A. Sensory neurones lack an axon completely.
2. B. Sensory neurones have a long dendron and a short axon with the cell body in a ganglion.
3. C. Sensory neurones have multiple short dendrons attached directly to terminal effectors.
4. D. Sensory neurones contain no myelin sheath.

7. What type of response is a muscle contraction triggered by touching a hot iron?

1. A. Voluntary action
2. B. Involuntary reflex action
3. C. Endocrine response
4. D. Learned behavior

8. Depressant drugs such as alcohol affect synaptic transmission by:

1. A. Accelerating impulse transmission across synapses
2. B. Inhibiting neurotransmitter binding or slowing central nervous system activity
3. C. Increasing myelin sheath production
4. D. Stimulating rapid growth of relay neurones

9. Where is the cell body of a sensory neurone located?

1. A. Ventral root ganglion
2. B. Dorsal root ganglion
3. C. Grey matter of the spinal cord
4. D. Presynaptic knob

10. Multiple sclerosis is a neurodegenerative disorder characterized by:

1. A. Destruction of the myelin sheath around axons
2. B. Hyperproduction of dopamine in synapses
3. C. Blockage of blood vessels in the cerebellum
4. D. Excessive accumulation of cerebrospinal fluid