Thoracic vertebrae can be distinguished from other vertebrae by the presence of

presence of facets.

Explanation:

Thorasic vertebrae are located in the thorax posterior and medial of the ribs. The are distinguished from lumbar and cervical vertebrae by the presence of facets on the side of articulation with the head of the ribs as well as facets on the transverse processes.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.