Author Question: The ability that humans have to perform very skilled movements such as writing is controlled by the: ... (Read 92 times)

frankwu · **on:** Jun 25, 2018

The ability that humans have to perform very skilled movements such as writing is controlled by the:

a. Basal ganglia.
b. Corticospinal tract.
c. Spinothalamic tract.
d. Extrapyramidal tract.

Question 2

A patient with a lack of oxygen to his heart will have pain in his chest and possibly in the shoulder, arms, or jaw. The nurse knows that the best explanation why this occurs is which one of these statements?

a. A problem exists with the sensory cortex and its ability to discriminate the location.
b. The lack of oxygen in his heart has resulted in decreased amount of oxygen to the areas experiencing the pain.
c. The sensory cortex does not have the ability to localize pain in the heart; consequently, the pain is felt elsewhere.
d. A lesion has developed in the dorsal root, which is preventing the sensation from being transmitted normally.

emily12345 · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: B
Corticospinal fibers mediate voluntary movement, particularly very skilled, discrete, and purposeful movements, such as writing. The corticospinal tract, also known as the pyramidal tract, is a newer, higher motor system that humans have that permits very skilled and purposeful movements. The other responses are not related to skilled movements.

Answer to Question 2

ANS: C
The sensory cortex is arranged in a specific pattern, forming a corresponding map of the body. Pain in the right hand is perceived at a specific spot on the map. Some organs, such as the heart, liver, and spleen, are absent from the brain map. Pain originating in these organs is referred because no felt image exists in which to have pain. Pain is felt by proxy, that is, by another body part that does have a felt image. The other responses are not correct explanations.