Analogy type questions:
$(1)$ The first vertebra is called the $Atlas$ vertebra.
$(2)$ Bones contain $Calcium$ salts.

(N/A) $(1)$ The first cervical vertebra $(C1)$ is known as the $Atlas$ vertebra,which supports the head.
$(2)$ The matrix of bones is rich in $Calcium$ salts (specifically $Calcium$ phosphate and $Calcium$ carbonate),which provide hardness and strength to the skeletal system.