Kele believes that he has broken his friend's iPod. He hasn't said anything, but his shoulders are hunched and he won't make eye contact with his friend. Kele is showing physical signs of

What is the most accurate statement about sleep and memory?

a. During sleep, neurons in the hippocampus are silent b. During sleep, more than 100 genes decrease their activity c. "offline" replay that occurs during sleep helps the cortex undergo LTP d. Contrary to what researchers expected, sleep has no measurable effect on memory

The myelin sheath is responsible for

A) receiving input from other neurons. B) carrying electrical impulses that send messages to other cells. C) insulating the axon. D) releasing the chemical neurotransmitters.