proteins

telegraph

hormonal

electrical impulses

skin cells

muscle cells

liver cells

stem cells

10 years

1 month

100 years

1 year

they regenerate very quickly

they help carry oxygen to different parts of your body

they do not have a nucleus

they are very long compared to other cells in the body

150 meters per second

1 foot per second

100 miles per hour

1 meter per second

pyramidal neurons

multipolar neurons

Purkinje neurons

bipolar neurons

the brain

muscle

nerve

wire

spinal cord

a nerve

brains

all of the above

muscle cells

prison cells

glial cells

stem cells