Question

an increased number of ependymal cells will the speed of communication.
increase
no change
decrease

Explanation:

Ependymal cells line the ventricles of the brain and the central canal of the spinal cord. Their main function is to produce cerebrospinal fluid. They do not play a role in the speed of neural communication. Neural communication speed is mainly related to factors like myelination (by Schwann cells in the PNS and oligodendrocytes in the CNS), axon diameter, etc. So an increased number of ependymal cells would have no impact on the speed of communication.

Answer:

No change