Lactase and carbonic anhydrase are examples of what type of substance?

They both are enzymes. Enzymes are usually substrate specific or reaction specific where an enzyme catalyzes or inhibits a reaction. Lactase works on lactose sugar but not on other sugars. This is an example of substrate specificity of enzyme.

Explanation:

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.