Assignment #5

The Nervous System II

Instructions: Please read each section/question carefully. Answer questions in complete sentences, and if/when you need to cite outside materials, please use footnotes. All work is to be typed, and may be submitted either by email or in class. This assignment is due no later than midnight Thursday August 5th. NO LATE PAPERS ACCEPTED.

Short Answer:

Damage to the facial and/or glossopharyngeal nerves will interfere with which special sense?

Why is the optic disc called the blind spot?

When entering a dark room on a sunny day, why does it take some time to see in the dark room?

Zak’s mom always told him to wait an hour after eating before swimming. Zak thought this was silly advice. Explain to Zak how physiologically sound this advice really is.

Case Study 1

While Fiona was wading barefoot in a tide pool at the beach, her left big toe was painfully stimulated by the pinch of a large crab.

Q1: Describe the pathways that brought the sensory information to the brain. Acknowledge each structure the neuron passed through in the CNS.

Q2: There are two pain pathways. Identify them and explain how both would function in Fiona’s situation.

Q3: How would you explain the fact that some serious injuries, such as those produced by a bullet entering the abdomen, may be relatively painless, but others, such as those that Fiona experience that involve crushing of the skin, may produce considerable discomfort?

Case Study 2

Ima Student went to see an otolaryngologist because she had difficulty hearing. A week previously she had a sinus infection and sore throat, but apparently that condition had resolved. After performing numerous tests, the doctor explained that she had a middle ear infection with an accumulation of fluid and that it was the result of the sinus infection and sore throat.

Q1: How would fluid in the middle ear reduce the ability to perceive sound?

Q2: Explain how a sore throat and sinus infection can result in a middle ear infection.

Case Study 3

Joe Salesman spots Max come into the auto showroom. He nonchalantly walks up and says ‘Hi’. After chatting for a few minutes and surveying Max’s face, Joe shows him a few cars. Joe notices that Max’s pupils have dilated, and he knows that Max is very interested in the model they are standing in front of.

Q1: How did Max’s pupils give him away? Which portion of the nervous system is ‘on’?

Case Study 4

Gina stumbled during her floor exercise during the gymnastics competition, but she was able to recover her balance.

Q1: Identify the main sensory receptors responsible for equilibrium. [PNS & CNS]

Q2: Identify the specific regions of her brain that work in maintaining her balance.