Candidates should be able to apply their knowledge of organelles in explaining adaptations of other eukaryotic cells.

A cell will have organelles to suit its job. The ultrastructure of a cell is just the detail inside it- so its types and amounts of organelles.

Here are some examples of where having more of an organelle fits a cells function:

• Mitochondria produce energy (ATP) so are beneficial in muscle cells which need energy for movement and epithelial cells which need energy for active transport.
• Endoplasmic reticulum produces protein (among other things) and so is needed in large amounts for cells that secrete enzymes like the epithelial cells and liver cells
• The same is true for ribosomes which will increase with ER as it covers the surface
• Golgi apparatus enables a cell to egest products like enzymes so would again be helpful in secretory cells; it also produces lysosomes which are needed a lot in phagocytic cells like white blood cells
• Microvilli are helpful in cells that need to absorb things as they increase the surface area, hence why there are so many in the epithelial cells

There can also be adaptations in the organelles- for example in a cell that needs a lot of energy the mitochondria may have more cistae so there is more respiration can happen.