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Biology for AP® Courses

Critical Thinking Questions

Biology for AP® CoursesCritical Thinking Questions

Critical Thinking Questions

9.

When you stick your hand in a bucket of ice, it grows numb after a while. Based on what you know regarding neuronal signaling, explain how the sensation of touch is blocked from signaling to the brain.

10.

Lidocaine is a local anesthetic that works by blocking voltage-gated sodium channels. Explain how blocking voltage-gated sodium channels would cause numbness and pain.

MISSING EXERCISE: tag:apbio-ch26-ex052MISSING EXERCISE: tag:apbio-ch26-ex053
11 .
What are the main differences between the sympathetic and parasympathetic nervous systems?
  1. The sympathetic nervous system is activated by stressful situations, whereas the parasympathetic nervous system resets organ function of sympathetic reactions and allows animals to “rest and digest.”
  2. The parasympathetic nervous system is activated by stressful situations, whereas the sympathetic nervous system resets organ function of sympathetic reactions and allows animals to “rest and digest.”
  3. The sympathetic nervous system is involved in unconscious body function control, whereas the parasympathetic nervous system is involved in conscious body function control.
  4. The parasympathetic nervous system is involved in unconscious body function control, whereas the sympathetic nervous system is involved in conscious body function control.
12 .
How is the sensory-somatic nervous system involved in sensing information and motor function?
  1. The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the peripheral nervous system. Motor information is sent to and from the central nervous system and the muscles.
  2. The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the central nervous system. Motor information is sent to and from the central nervous system and the muscles.
  3. The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the central nervous system. Motor information is sent to and from the peripheral nervous system and the muscles.
  4. The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the peripheral nervous system. Motor information is sent to and from the peripheral nervous system and the muscles.
13 .
Public speaking can be very stressful. How can anticipating giving a public speech stimulate the sympathetic nervous system?
  1. During stress, multiple preganglionic neurons can synapse on one postganglionic neuron, and the adrenal gland releases adrenaline.
  2. During stress, one preganglionic neuron can synapse on multiple postganglionic neurons, and the thymus gland releases norepinephrine.
  3. During stress, one postganglionic neuron can synapse on multiple preganglionic neurons, and the adrenal gland releases norepinephrine.
  4. During stress, one preganglionic neuron can synapse on multiple postganglionic neurons, and the adrenal gland releases norepinephrine.
14 .
(credit: modification of work by Belloy ME, Napolioni V, Greicius MD/Neuron)

The apolipoprotein E (APOE) gene is associated with Alzheimer's disease. This gene has three possible alleles, E2, E3 and E4. Recall that each person has two alleles for a gene. The graph shows Alzheimer risk of a person and the APOE allele combination they have.

What can we conclude from this graph?

  1. E4 allele increases likelihood of having Alzheimer's. E4/E4 combination has the most risk.
  2. E3 allele increases likelihood of having Alzheimer's. E3/E4 combination has the most risk.
  3. E2 allele increases likelihood of having Alzheimer's. E2/E3 combination has the most risk.
  4. People with different alleles for APOE have a higher risk for Alzheimer's.
15 .
(credit: modification of work by Ren, Liyan et al./PloS one)

The graph shows serotonin levels on two groups of mice. The "KO" group mice have depression (artificially induced for the study) and the "Con" group is the control group.

What is a conclusion that can be drawn from this graph?

  1. Mice with depression do not produce any serotonin.
  2. Mice with depression produce the same amounts of serotonin as other mice.
  3. Mice with depression produce more serotonin than other mice.
  4. Mice with depression produce less serotonin than other mice.
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