Introduction: Cellular Structure and Function
All organisms are made of cells. Complex organisms (such as humans) are made up of collections of highly specialized cells, each with its own specific function. Different types of cells have evolved specific shapes and properties which help them do their jobs inside the organism.
Still Image:
Field of human red blood cells
Individual disk-shaped red blood cells appear colorless when viewed under a microscope. The pink tint on the left of the image is due to the clotting of several layers of red blood cells.
A drop of human blood was diluted in saline solution, then sandwiched between a slide and coverslip (using a thin strip of silicon rubber as a spacer). The image was taken on an inverted compound microscope using a 40x DIC objective and a digital camera.