Do now! Can you spell the following words CORRECTLY in the back of your book? Nucleas, cytopllasm, clorroplasts, sell, vacoule. Cells What is a cell? What is a cell? A cell is the very smallest unit of living matter. All living things, including plants and animals, are made up of cells. What is a cell? A cell is like a chemical factory. What is a cell? There are many different kinds of cells, doing many different jobs in a plant or animal. Animal and plant cells The two kinds you need to be most familiar with are simple animal and plant cells. Cell parts All cells have some parts in common. Cell membrane One part found in all cells is the cell membrane. Cell membrane The cell membrane surrounds the cell and holds the cell together. It controls what chemicals can enter and leave the cell. Nucleus Another part found in all cells is the nucleus. Nucleus The nucleus controls the cell. Inside the nucleus is DNA which contains genetic information. Cytoplasm All cells also contain cytoplasm. Cytoplasm Cytoplasm is a jelly-like mixture of chemicals where most of the work of the cell takes place. Plant cell parts Plant cells may contain some extra parts. Chloroplasts (plant cells) Chloroplasts which are disc shaped and contain chlorophyll for photosynthesis. Cell wall (plant cells) A cell wall which is a strong outer layer to support the cell and give it shape. Vacuole (plant cells) A vacuole where the plant cell stores sap (the food that it has made; a mixture of sugars, salts and water). To summarise: More complicated! In reality, most cells are much more complicated than this! Interesting cell facts: Like all living things, cells die. If you watched a clock for one minute, about three billion cells in your body die. x 3000000000 Interesting cell facts: In that same minute, about three billion cells divided so that all the cells that died were replaced. x 3000000000 Interesting cell facts: Dead skin cells flake off and dead cells from internal organs will pass through and out of the body with waste products. Interesting cell facts: The length of time cells live can vary. For example, white blood cells only live for thirteen days, red blood cells live for about one hundred and twenty days, liver cells live about eighteen months, and nerve cells can live up to one hundred years! Plant and animal cells Can you stick in and complete the small sheet “Plant and animal cells”? Building cells Can you then complete the sheets “building plant cells” and “Building animal cells”? Oh no! Palisade cell Special cells Nerve cell There are many different types of cells to do different jobs in plants and animals. Using pages 10 and 11 of your book, can you sketch the 5 cells on this slide and write 2 sentences below each describing i. what they do ii. How they are adapted to do their job Root hair cell Muscle cells Ciliated epithelial cell