Ostrich eggshell is composed of 96% crystalline calcite and 4% organic material, mostly proteins. The thickness is made up of three different layers that vary in structure and thickness. The hardness of the shell is 3 on the Mohs scale. Pretty solid!
Elderly people are most at risk
from minor trauma that results in serious spinal cord injury because of
preexisting degenerative vertebral disorders. Males are more prone to spinal
cord injuries than females but not as a result of preexisting disorder. This
may be related to an increased involvement in contact sports or a propensity to
participate in high risk activities. Neither females nor infants are at any
particular risk for spinal cord injuries.
Notchochord, morphology, chordates
Answer:
difficult
Explanation:
I guessed because I'm smart