Leukocytes are part of the intergumentary system are surface barriers to infection cannot reproduce without a host cell are produced and stored in the thymus and spleen

Leukocytes cell

Explanation:

Also known as white blood cell are colorless cell in the blood and body fluid , active in fighting foreign bodies and diseases in human system by producing antibodies , ingesting strange bodies ,and destroying cancer cells .

It is produced by hematopoietic cells

There are five different types of it with different functions of disease fighting namely basophils , neutrophils ,eosinophils,monocytes and lymphocytes.

Exercise activities can increase the number in the system while rest takes it down

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d. changes in climate and historical records

hope this