Alzheimer's disease is a common form of dementia affecting millions of people, especially the elderly. Two regions of the brain are particularly affected, often shrinking dramatically and accumulating large deposits of extracellular material. Based on your knowledge of memory, what two brain regions do you think these are? Explain.

DRAW IT The reflex that pulls your hand away when you prick your finger on a sharp object relies on a neuronal circuit with two synapses in the spinal cord. (a) Using a circle to represent a cross section of the spinal cord, draw the circuit. Label the types of neurons, the direction of information flow in each, and the locations of synapses.

Compare and contrast the somatic nervous system and autonomic nervous system.

Why is memory thought to involve changes in particular synapses?a. At some synapses, more neurotransmitters are released after learning takes place.b. At some synapses, a different type of neurotransmitter is released after learning takes place.c. When researchers stimulated certain neurons electrically, individuals replayed memories.d. When researchers changed synapses in the brains of patients during surgery, the patients' memories changed.

Design an experiment with a group of taxi drivers in a new city to examine the role of neuroplasticity on learning. Assume you have the ability to image their brains to measure changes in the volume of gray matter.

Which would be present in an animal with a nerve net?

What is the difference between a neuron and a nerve?

A neuron that transmits an impulse to the central nervous system after the neuron is stimulated by the environment is called a(n) __________.

Which of the following is specific to the central nervous system?