The removal and examination of tissue, cells, or fluids from the living body.


A red blood cell; the major cell component of blood whose primary function is to carry oxygen.


An iron-containing protein that binds oxygen and is the primary component of erythrocytes.


The study of tissues.


A white blood cell; primary function is defense against foreign materials as part of the immune system.


The fluid part especially of blood or lymph.


A component of mammalian blood that lacks a nucleus and is derived from fragments of megakaryocyte cytoplasm, and that assists in blood clotting, also called a thrombocyte.


An integrated group of cells with a common function, structure, or both.

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