electrical impulses

telegraph

hormonal

proteins

the brain

nerve

wire

muscle

brains

spinal cord

a nerve

all of the above

1 year

10 years

100 years

1 month

pyramidal neurons

Purkinje neurons

multipolar neurons

bipolar neurons

liver cells

muscle cells

skin cells

stem cells

100 miles per hour

150 meters per second

1 foot per second

1 meter per second

they help carry oxygen to different parts of your body

they are very long compared to other cells in the body

they regenerate very quickly

they do not have a nucleus

stem cells

prison cells

glial cells

muscle cells