proteins

telegraph

hormonal

electrical impulses

brains

spinal cord

a nerve

all of the above

1 year

100 years

10 years

1 month

wire

the brain

nerve

muscle

stem cells

muscle cells

liver cells

skin cells

they help carry oxygen to different parts of your body

they regenerate very quickly

they are very long compared to other cells in the body

they do not have a nucleus

100 miles per hour

1 foot per second

150 meters per second

1 meter per second

bipolar neurons

Purkinje neurons

pyramidal neurons

multipolar neurons

muscle cells

prison cells

stem cells

glial cells