hormonal

telegraph

electrical impulses

proteins

spinal cord

all of the above

brains

a nerve

muscle

nerve

wire

the brain

100 miles per hour

1 foot per second

1 meter per second

150 meters per second

they help carry oxygen to different parts of your body

they regenerate very quickly

they do not have a nucleus

they are very long compared to other cells in the body

multipolar neurons

pyramidal neurons

Purkinje neurons

bipolar neurons

muscle cells

skin cells

stem cells

liver cells

prison cells

muscle cells

stem cells

glial cells

100 years

1 year

1 month

10 years