telegraph

electrical impulses

hormonal

proteins

all of the above

spinal cord

a nerve

brains

the brain

nerve

muscle

wire

150 meters per second

100 miles per hour

1 meter per second

1 foot per second

liver cells

skin cells

muscle cells

stem cells

Purkinje neurons

bipolar neurons

multipolar neurons

pyramidal neurons

10 years

1 month

100 years

1 year

prison cells

muscle cells

stem cells

glial cells

they regenerate very quickly

they do not have a nucleus

they are very long compared to other cells in the body

they help carry oxygen to different parts of your body