As the summer fades into fall, I thought I should use the sunflower theme to try to keep a little bit of summer around a teeny bit longer...
In Unit 3 we will be focusing on the remaining three tissue types: connective, muscle, and nervous. We have already learned about epithelial tissue in the last unit.
Tissues contain cells, and may also contain some acellular material. In epithelial tissue, we saw that the cells were so tightly packed that there was no room for acellular material, except for underneath it (the basement membrane). But, you will see that in order to understand connective tissue, you will need to start paying attention to the acellular material which lies between the cells (called the extracellular matrix) as well as the cells. Also, there may be more than one cell type within a certain tissue. Epithelial tissue had cells of different shapes, but not typically within the same bit of epithelial tissue (so, simple squamous epithelium only had squamous cells in it, and no columnar cells were ever found). In connective tissue you will see that cells may differ not only in shape, but also in function.
Here are some general descriptions of the four types of tissues, to highlight their differences in features noted above.
We will go through connective, muscular, and nervous tissues this week. Then, next week, we will finish this off by finishing the skin unit... that way, we will put the dermis (connective tissue) back underneath the epidermis that we already learned about last week. We will also finish understanding the skin as an organ by learning about how the dermis, epidermis, and even hypodermis function for our bodies.
To keep going this week, though, connect at the top of this page to any of the unit pages.
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