I think its the left one (sorry if im wrong)
Answer:
d. cerebellum.
Explanation:
The cerebellum, which is part of the hindbrain, is a small structure made of a covering of white cortex found under the hemispheres of the cerebral cortex. The cerebellum plays a major role in the control and coordination of all physical movements such as balance, control, etc, that has to deal with smooth and balanced activities of the muscle.
A damage to the cerebellum would most likely lead to impaired motor coordination, staggering, inability to judge distance or when to stop.
Axons with large diameters conduct impulse faster than those with small diameters. Also Myelinated axons conduct impulse faster than unmyelinated axons. Axons with the largest diameter are all myelinated, therefore they are capable of salatory conduction (Impulses jump from one myelinated node to another). The smallest diameter axons are unmyelinated, so their conduction is continuous.
I hope this helps. :) :)
Velocity
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