Introduction: Blood Cells
Blood contains several different types of cells. Some cells, such as red blood cells, carry oxygen to other cells. Other types of cells, such as white blood cells or leukocytes, provide protection from foreign cells and infectious agents. Cell fragments called platelets provide protection against bleeding. The red blood cells of different animals can have different structures.

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Human white blood cells 2
White blood cells are an important part of our immune system, moving to sites of infection to engulf and destroy microbes. In this movie, white blood cells, called granulocytes crawl along a glass slide. Disk-shaped red blood cells are also visible. The 'spiky' red blood cells are an artifact of the slide preparation.

Elapsed time 7 minutes.
A drop of blood from a fingerprick was placed on a slide, diluted slightly with saline solution, then incubated at 37° Celsius for 30 minutes. Coagulated red blood cells were washed away with saline solution. A droplet of saline with human serum was put on the remaining cells, along with a silicon rubber spacer and coverslip. Images were taken on an inverted compound microscope at 37° C with a 64x DIC objective and digital camera.