TEM - mitochondria, nucleus and rough ER

A transmission electron micrograph showing a mitochondrion, part of a nucleus and rough endoplasmic reticulum The section has been cut from a frozen section. This process preserves the sample without dehydration thereby preventing shrinkage. Although this type of image appears less sharp than the traditionally fixed material it gives a truer picture of the cell contents. The membranes show the characteristic dark, light, dark pattern of lipid bilayers and many cristae are visible inside the mitochondria.