Science 9 Bio 1
Cell Structure & Cell Division
Watch video https://www.youtube.com/watch?v=URUJD5NEXC8
Recall from Sc 8 that almost all life on earth occurs in the form of Cells. Individual
Cells can only grow to a certain size because as cells get larger, their surface area
grows more slowly than their volume. At a certain size it is impossible for the cell
to continue functioning.
As a result, living things grow through the process of Cell Division. Cell Division
also allows an organism to reproduce and repair itself.
In multi-celled organisms like humans, different cells divide at different rates. For
example, the cells in your stomach are replaced by cell division in about 8 days.
Where nerve cells hardly change throughout the course of your life.
Almost every part of an animal or a plant is composed of protein. There are
proteins that make up your skin, your bones, your nerve cells and the major
structures of your body including most of the parts within a cell. Proteins also
make up the various enzymes that are used to digest your food and send
messages throughout your body. One of the most important functions of a cell is
the production of proteins.
The “blueprint” for all the proteins in your body is found in a chemical called DNA
which is enclosed by the nucleus in eukaryotic organisms. In bacteria and other
prokaryotic cells the DNA floats in the cytoplasm.
Page 39 in text
1. Draw a picture of both an Animal and a Plant Cell
2. Label the various parts of each cell
3. At the bottom of your drawing, give an explanation of each of parts of the
cell.
Science 9 Bio 1