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Biology > Animal Cells

In this section there are two diagrams, one is simple in its construction (Fig 1) and may be appropriate for secondary schools (GCSE/KS3-4) whereas the more detailed diagram (Fig 2) contains more organelles and may be more suitable for AS/A level and other vocational sciences. Remember you are free to copy any of these diagrams for use in your school and/or Virtual Learning Environment (VLE) Scroll down to the bottom of this page for the diagrams.

Animal cells all have a nucleus, cytoplasm and a cell membrane. Unlike plant cells, animal cells do not have a cell wall, instead the thin cell membrane controls what may enter and leave the cell and also gives the cell it’s shape.

The cytoplasm is a jelly-like substance where chemical reactions take place which keep the cell alive. It is in the cytoplasm that other organelles reside.

The nucleus usually contains the genetic material for the cell and as such, contains the DNA which determines what job the cell does.

Cell organelles are structures within a cell which do a particular job. They can be thought of as being like organs within a living body.

Protein synthesis takes place within Ribosomes. Some are free to move around the cytoplasm while others are attached to the rough Endoplasmic Reticulum (ER)

Lysosomes are sacs of enzymes which break down unwanted or old parts of the cell into organic molecules that may be reused.

The Endoplasmic Reticulum (ER) is a series of interconnected tunnels, some rough and some smooth. The smooth variety has no attached ribosomes whereas the rough type does. The rough ER takes in proteins made by the ribosomes so that they cannot escape into the cytoplasm.

Mitochondria are organelles, large in form where oxygen combines with food to produce ATP (the food source for the cell). They contain their own DNA and can reproduce on their own, independently from the cell.

The Golgi Apparatus is little understood although it is believed that it transforms proteins from the ER and moves them on to their next stage.

The Centrosome is the organelle where cell microtubles are produced. During animal cell division, the centrosome divides and the centrioles replicate. The centrioles are a pair of small organelles within the centrosome.

The table below shows the main differences between plant and animal cells.

Plant Cells Animal Cells
Tough cellulose cell walls No cell wall
Nucleus to one side of cell Central nucleus
Large permanent vacuole Some have small vacuoles
Many chloroplasts No chloroplasts


Fig 1: Simple animal cell
Fig 1:
Simple animal cell


Fig 2: Animal cell with organelles
Fig 2:
Animal cell with organelles