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Worksheet: Tissues. |
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Aims & Objectives Introduction The four basic tissue types Epithelium |
Level: BeginnerBy the end of this worksheet you will be able to:
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| In order to understand tissues you should have completed the section on cells. A tissue is a group of cells and their supporting structures, organised to perform a function. Or to put it another way, when cells get together and decide to do something, they form a tissue. | ||||||||
| There are only four fundamental tissue types. Again, when the cells join together, they only do so in one of four ways: | ||||||||
| Epithelial tissue is the body's wrapping paper. It's also known as Epithelium. It comes in two varieties depending on whether we're looking at function or structure. Epithelium can have one of two functions: |
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| Covering and lining epithelium is everywhere. It's your skin (although remember that skin is a complex structure made up of a number of layers), it covers your internal organs, it lines your intestine and your body cavities. It occurs in sheets. | ||||||||
| Glandular epithelium is the secreting surface of glands. It consists of sheets of specialised cells which produce hormones. | ||||||||
Structurally epithelium can be
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| Simple epithilium is a sheet of cells just a single cell thick. | ||||||||
| Compound epithelium is, as you'd expect, more complex than simple. | ||||||||
| That's as far as we'll go with epithelium in this worksheet. We'll look at the different types of epithelium in more detail in later worksheets. | ||||||||
| In connective tissue the cells are spaced further apart and the gap between the cells is filled with an intercellular substance, just what that substance is will depend on the connective tissue's job. The name can be a bit confusing - blood is a connective tissue, in which case the intercellular substance is a fluid called plasma. Bone is a connective tissue, the intercellular material there being rock, effectively. |
