Read the following two case studies and answer the questions that follow:
CASE STUDY #1
Chen is cooking dinner for his family. He moves to pull a pot off the stove and accidently touches the burner. Reflexively he pulls his finger away from the stove and immediately feels the pain.
1. What is the role of the brain and spinal cord in this response?
2. Describe the three types of neurons involved in this response and their role in the reflex arc. Explain the withdrawal reflex that results in Chen moving his hand away from the stove.
3. Evolutionarily, why do you think the human body has this system in place? Why is this reflex important?
4. Chen’s wife, Amira, was born with congenital insensitivity to pain, a condition that inhibits the ability to perceive physical pain. Find a reliable source related to congenital insensitivity to pain and address the following questions:
a. What is congenital insensitivity to pain?
b. What are some of the signs and symptoms of this condition?
c. In this week’s reading, you learned about the role of sodium ions in the conduction of nerve impulses. Individuals with congenital insensitivity to pain are unable to make a sodium channel called NaVi.7. How is this related to the signs and symptoms of the disease?
d. What might happen if Amira had touched the burner? How would her response be different than Chen’s?
e.What advice would you give to a child who has this condition and is interested in playing contact sports? What would happen if this child experienced a fracture?
CASE STUDY #2
Monica just celebrated her 30th birthday. During her annual physical exam, Monica mentions symptoms she has been experiencing over the last few months. These symptoms include blurred vision, numbness in her fingers and face, dizziness, fatigue, weakness, and depression. Although Monica believes that these symptoms are related to stress and aging, her physician is concerned and suspects that Monica may have multiple sclerosis (MS).
1. What is MS?
2. What is the main cell structure affected in MS? What is the role of this structure?
3. How does the impact of MS on this cell structure help to explain Monica’s symptoms? Include an explanation of how the action potential of a neuron is affected in MS.
What is the treatment for multiple sclerosis? What is the mechanism of action of the treatment?
4. The origin or etiology of MS is not clear. Find a reliable source related to the etiology of multiple sclerosis. Based on your research, what do scientists hypothesize to be the causes of MS? Include the appropriate reference and citation for the source you consulted.
