Cell Structure (TEM)

Cell Structure

The basic subcellular structures of an eukaryotic cell as seen by transmission electron microscopy (TEM).

Try to identify the cell borders and nuclei.

Switch between the grayscale and color images (see above) to help identify the following structures:

(dark green) - portions visible in cells 1, 2 and 4
(blue) - part of nuclei for cells 1, 2 and 4 are visible
- Nuclear Envelope (purple) - composed of an inner and outer nuclear membrane.
(green) - ribosomes appear as clusters of small, dark particles.

Organelles are specialized membrane-enclosed structures in the cytoplasm of eukaryotic cells.

Identify these organelles:

(yellow) - stack of flattened membrane discs (cisterna) involved in the sorting of proteins produced by rough endoplasmic reticulum. It is larger in secretory cells.
(red) - number, size and shape varies widely depending on cell type. Two membranes separated by a narrow space.
- Outer Membrane - smooth surface that contains the mitochondria.
- Inner Membrane - forms flat extensions (called cristae) into the matrix of the mitochondria.
(cyan) - amount and shape varies widely depending on cell type. Membrane sacs found as flattened sacs (cristernae) and vesicles.
- Smooth Endoplasmic Reticulum - function depends on cell type.
- Rough Endoplasmic Reticulum - external surface has bound ribosomes involved in protein synthesis.