Neuron.
*Tip* Try googling the question. You'll be surprised.
Cell, Tissue, Organ, Organ System
(Hope this Helps)
They are also used to see what kinds of major geological events took place such as earthquakes or major weather changes such as ice storms.
Tendons :may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure. A ligament: is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable.
