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:
Zebrafish red blood cells
Individual red blood cells from a zebrafish appear colorless when viewed under a microscope. (Images of individual human, sheep, and zebrafish red blood cells were taken at the same magnification and appear to scale.)
A drop of 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.