In: Anatomy and Physiology
Answer - (A) Statement A is correct.
Leukocytes are also called as white blood cells which is a part of the our blood including the red blood cells and platelets.
leukocytes are concerned with the immune system cells of the body , wbc plays a very important role in fighting with the foreign harmful antigens.
They are of 5 sub parts which are :
these are the 5 types of leucocytes or whilte blood cells in which lymphocytes , monocytes and neutrophils are very majorly involved in making the antibody and kill the harmful antigens or microbes.
SO the first statement is true that lymphocytes are always leukocytes because lymphocytes are the part of leukocytes only but leukocytes are not always lymphocytes because leukocytes are of 5 types so it can also be neutrophil or monocytes etc.
Now second option is wrong because cancerous condition of lymphocytes is called as lymphocytic leukemia and not myelocytic leukemia ; myelocytic leukemia is a cancerous condition of blood cells other than lymphocytes all other cells including red blood cells and platelets may also include in myelocytic leukemia.
While the destruction or loss of the leucocytes or wbc is called as leukopenia and not a rise in WBC .
Leukemia is the blood cancer and not a term used for rise in white blood cells.
So conclusively the statement A is true because all lymphocytes are leukocytes but all leukocytes are not lymphocytes.