The typical cell

Where the light microscope stops, the electron microscope begins. On the information it gives, one diagram has been built that appears in book after book — the typical cell.

Organelles

The very small structures held within a cell, each carrying out a function of its own, are called organelles. Which kinds a cell holds, and how many of each, varies with the job that cell does.

The typical cell

A cell drawn so as to contain every organelle a cell could have is called a typical cell.

Do not go looking for one

No such cell exists in the living world. It was never seen down a microscope; it is assembled for teaching. What can be found in living things are many different cells, each holding some of the organelles the typical cell shows.

Figure to be added

Figure 6.6 — the typical plant cell, constructed from electron microscope information, with the cell wall, plasma membrane, nucleus, nucleolus, chloroplast, mitochondrion, ribosomes, Golgi complex, rough endoplasmic reticulum, vacuole, tonoplast and cell sap labelled.

Figure to be added

Figure 6.7 — the typical animal cell, constructed from electron microscope information, with the plasma membrane, nucleus, nucleolus, centrosome, mitochondrion, Golgi complex, ribosomes and rough and smooth endoplasmic reticulum labelled.

The two figures are worth comparing

Most of the organelles in figures 6.6 and 6.7 are common to both. But a few parts appear in the plant cell alone. The next page does nothing but set those differences down as a list.