Question

Demifacets are present at
a. Thoracic vertebra
b. Lumbar vertebra
c. Sacral vertebra
d. Cervical vertebrae except $C_{7}$

Answer 1

Hint: The facet is the flat or nearly kind of flat surface on the bone. Demifacet is none other than the half of the facets which are mainly seen on the ribs two through nine. The cervical vertebra is present in the neck.

Complete answer:
As there are a total of twelve thoracic vertebrae present. Mainly their transverse processes and bodies have a facet that has total articulate $T_{1} - T_{12}$ with the ribs.

It is seen that the head of the following rib is mainly joined to the two thoracic vertebrae via the help of coastal demifacets, where half of the facet is on the superior vertebra, and mainly the rest of the half of the facet is seen to be on the inferior vertebra.

The given demifacet can be semicircular or semilunar. Mainly the laminae of the thoracic vertebrae are generally short, broad, and thick.

They help and allow some of the movements of the spine in the thoracic area.
The lumbar vertebra mainly has a total of five cylindrical bones that will form the spine in the lower back.

The sacral is the triangular-shaped bone which is placed between the hip bones.
The transverse foramina that only contain accessory veins are known as cervical vertebrae except for $C_{7}$.

Hence, The correct answer is option (A).

Note: The thoracic vertebrae mainly lie in the wall of the posterior of the thorax with the twelve pairs of the ribs attached to them. Thoracic vertebrae mainly have the bodies of the intermediate size which are differentiated by the presence of facets and by the long slender spines.