Messages are passed through many billions of spaces among neurons called

Messages are passed through many billions of spaces among neurons called
 
  a. nodes. c. synapses.
  b. glial cells. d. hormones.

Question 2

Which of the following receives electrochemical messages from other cells and transfers them to the cell body?
 
  a. dendrites c. myelin sheaths
  b. axons d. nuclei

Question 3

It has been estimated that the adult brain has up to ____ neurons.
 
  a. 1 million c. 1 billion
  b. 100 million d. 100 billion

Question 4

What characteristic distinguishes humans from all other animas the most?
 
  a. the ability to live in societies c. walking upright
  b. a distinct digestive system d. intelligence

Question 5

Positron emission tomography (PET) assesses the metabolic activity of
 
  a. the brain, through measuring changes of blood flow.
  b. glucose or oxygen in the brain, by following the path of a radioactive tracer injected intravenously.
  c. the diffusion of water in the brain tissue, permitting the imaging of the white matter tracts.
  d. brain tissue after exposure to a strong magnetic field.