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As you have already learned, everything that lives is made up of cells. And the cells themselves are made up of many different parts right down to their molecules.
In fact, what scientists call the universal principle of life is defined as the specific interaction of molecules with one another. Now lets find out a little more about cells and molecules. There are many different cells that do many different things. But all of these cells fall into one of the two main categories: prokaryotic cells and
eukaryotic cells.
These cells are more alike than they are different. So first lets talk about what prokaryotic and eukaryotic cells have in common.
•Both have DNA as their genetic material (its DNA that tells cells what kind of cells they should be).
•Both are covered by a cell membrane.
•Both contain RNA.
•Both are made from the same basic chemicals: carbohydrates, proteins, nucleic acid, minerals, fats and vitamins.
•Both have ribosomes (the structures on which proteins are made).
•Both regulate the flow of the nutrients and wastes that enter and leave them.
•Both have similar basic metabolism (life processes) like photosynthesis and reproduction.
•Both require a supply of energy.
•Both are highly regulated by elaborate sensing systems ("chemical noses) that make them aware of the reactions within them and the environment around them.
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papashankz 11 months ago
thanks that helped a lot :)
16simplyunique16 1 year ago