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LE CERVEAU À TOUS LES NIVEAUX! Polygamie_feminine.mpg. Hormones_printemps.mpg. Cell Size and Scale. Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0.1 mm long. That means that under the right conditions, you might be able to see an ameoba proteus, a human egg, and a paramecium without using magnification. A magnifying glass can help you to see them more clearly, but they will still look tiny. Smaller cells are easily visible under a light microscope. It's even possible to make out structures within the cell, such as the nucleus, mitochondria and chloroplasts. Light microscopes use a system of lenses to magnify an image. The power of a light microscope is limited by the wavelength of visible light, which is about 500 nm.

To see anything smaller than 500 nm, you will need an electron microscope. Adenine The label on the nucleotide is not quite accurate. How can an X chromosome be nearly as big as the head of the sperm cell? No, this isn't a mistake. Carbon The size of the carbon atom is based on its van der Waals radius. La Cellule Animale. Video 4 - Chantal.mpg.