Why do some researchers prefer to use embryonic stem cells in medical research

The stem cells could assist in medicine in three usual manners, that is, in discovering drugs, cell-based therapies, and for basic knowledge. The embryonic stem cells could be utilized to produce more unique tissues, which have been lost because of an injury or disease.  

The embryonic stem cells could be developed into more unique cells for testing potential drugs. The cancer cells cultures are used already for testing cancer drugs, and developing embryonic stem cells into the liver, heart, or nerve cells could be beneficial for examining drugs, which influences these organs.  

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.

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.