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Plant and animal cells are both eukaryotes. They contain several types of organelle within the cytoplasm and these organelles each have a distinctive shape and size.
Many organelles are present in all eukaryotic cells, although the number that a specific cell contains depends on its function. Each organelle has a particular job allocated to it, so by having various organelles in each cell there is division of labour and the cell can perform its function efficiently. For example, cells needing lots of energy contain many mitochondria and cells that synthesise very actively need a very extensive endoplasmic reticulum and many golgi bodies.
The nucleus is the most obvious structure in a eukaryotic cell; it is usually spherical and about 10µm across. ... Virtually all eukaryotic cells have a nucleus (red blood cells lose theirs and so are enucleate for most of their life-span). ... The DNA is the same in most cells of a particular individual, but depending on the specific cell type, some genes may be turned on or off. ...
Ribosomes are tiny, dense organelles and are about 20nm in diameter.They are present in great numbers in most eukaryotic cells. ... It runs through the cytoplasm of all eukaryotic cells. ... Some of the most important substances produced are phospholipids, which are the main component of the membrane round the cell and around many of the organelles within it. ... Smooth ER also contains enzymes for detoxifying chemicals, including drugs and pesticides and it acts as a storage site for calcium in skeletal muscle cells. It is extensive in cells that secrete steroid hormones and is involved in the detoxification of urea in the liver. ... ’ Golgi apparatus are only found in animal cells. ...
Lysosomes are common in animal cells but rare in plant cells. ... Each lysosome contains about forty enzymes and these can be used in a highly controlled way to break down foreign bodies or worn out organelles in a cell. Lysosomes are especially important in white blood cells that are used to destroy bacteria. ...
Other membrane bound organelles are mitochondria. ... Eukaryotic cells usually contain many of these organelles and without them a cell would not have the energy to function.
Chloroplasts are an organelle found in all higher plant cells. ... A substance called chlorophyll is contained within these organelles, giving the cell a green colour.
Approximate Word count = 1900
Approximate Pages = 7.6
(250 words per page double spaced)
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