Diencephalon is a dinosaur, right?

Sleep disorders are often more common in childhood, most likely because children

a) sleep very deeply and spend more time in deep sleep b) are so easily awakened in the deep sleep stage c) spend less time in REM sleep than adults d) need less sleep than adults

In addition to providing structural support and protection for the axon of a neuron, what other very important function is served by the presence of a myelin sheath?

a. Dendritic stimulation b. Speeding up and strengthening neural messages. c. Facilitating re-uptake in the synaptic gap. d. Inhibiting the growth of pain-sensitive neurons.