Your roommate is on an ultra-low fat diet to try to lose weight. Given what you know about structure of the nervous system, what advice would you give him?

Question

A.  "You should drink large quantities of water, because the brain is mostly water."
B.  "Good for you! Losing weight by any means necessary can only help your brain."
C.  "You should eat some healthy unsaturated fats, like those found in fish, olive oil, and nuts, because your brain needs fatty acids to build the myelin sheaths around your axons."
D.  "You should eat trans fats, from donuts, because 'trans' is short for neurotransmission."

Clarify Question
· What is the key concept addressed by the question?
· What type of thinking is required?

  Gather Content/Choose Answer
· What do you already know about components of the nervous system? What other information is related to the question?

  Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
 

Answer 1

C.  "You should eat some healthy unsaturated fats, like those found in fish, olive oil, and nuts, because your brain needs fatty acids to build the myelin sheaths around your axons."

Clarify Question
· What is the key concept addressed by the question?
        o The question is asking you to give diet advice to your friend trying to lose weight.
· What type of thinking is required?
        o This question is asking you to evaluate the potential negative consequences of an ultra-low fat diet on the nervous system.

  Gather Content/Choose Answer
· What do you already know about components of the nervous system? What other information is related to the question?
        o To solve this problem, you’ll need to apply your knowledge of the importance of lipids in the nervous system. Myelin is the lipid-rich layer wrapped around axons to insulate them. This insulation speeds up conduction of action potentials. Thus, lipids are vital for the nervous system to operate properly. Axon tracts in the brain and spinal cord are called white matter because this lipid-rich material has a shiny, white appearance and makes up a considerable portion of the nervous system. Thus, a diet with some lipids is necessary for a healthy nervous system. Drinking sufficient water is also important to one’s health, but the question addresses fat and not water. Trans fats is not short for neurotransmission so you can eliminate that answer. Losing weight by any extreme means can actually be very dangerous for your health, but eating moderate levels of healthy, unsaturated fats can provide the lipids needed to myelinate your axons.

  Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        o If you figured out the correct answer, good job! If not, where did you go wrong? Did you think that the answer was (a) because our brain, as well as most of our cells, are primarily water? This is true but the diet your roommate is on is an ultra-low fat diet, and water was not mentioned. Did you get fooled into thinking that trans fats really is short for neurotransmitter fats?