Transcript Cells
Cells and Microorganisms Organisms All living things are organisms. Organisms NOT Organisms History of the Cell You’ve probably seen cork stoppers in bottles or cork on bulletin boards. Cork comes from the bark of an oak tree, an organism. In 1665, Robert Hooke, an English scientist, observed a thin layer of cork though a microscope. Because Hooke thought the structures he saw looked like tiny rooms, he named them cells. History of the Cell Hooke’s description of cells made scientists want to know more about them. Using microscopes, they learned that all living things are made of cells. A cell is the basic unit of structure and function in living things. Cells are microscopic, meaning that they cannot be seen with the naked eye. Plant & Animal Cells There are 2 types of cells:Plants and animals have different types of cells, each with its own job. The different cells work together to carry out life functions that keep an organism alive and healthy. For example, your body has cells that help you break down food. It has cells that carry oxygen to other cells. It also has cells that carry away waste materials. To perform its own functions, each cell contains structures called organelles. Each type of organelle has a certain function that helps keep the cell alive. Animal Cells ALL animals contain animal cells. Remember: Humans are considered animals, too! Animal Cell: Organelles (Parts) Nucleus Cytoplasm Cell Membrane *Animal cells are round in shape. What’s Their Function? Cell Membrane: Holds a the cell together and separates it from its surroundings. Allows nutrients and water to pass in and out of the cell. Nucleus: Directs and controls ALL cell activities. Cytoplasm: A jelly like fluid containing chemicals that keep the cell healthy. Plant Cells ALL plants contain plant cells. Plant Cell: Organelles (Parts) Nucleus Cell Membrane Cell Wall Chloroplast Cytoplasm *Plant cells are rectangular in shape. What’s Their Function? Cell Wall: Supports and protects the outside of the Cell Membrane: Holds a the cell together and plant cell. separates it from its surroundings. Allows nutrients and water to pass in and out of the cell. Nucleus: Directs and controls ALL cell activities. Chloroplasts: Makes food for the plant cell. Cytoplasm: A jelly-like fluid containing chemicals that keep the cell healthy. Let’s Review Cells Animal Cells Both Nucleus Cytoplasm Cell Membrane Plant Cells Cell Wall Chloroplasts Single-Celled Organisms Bacteria Virus Protozoa Multi-Celled Organisms Flower Cat Bee Tree What’s the Difference? Single Celled Organisms The entire organism contains 1 cell Usually microscopic Multi Celled Organisms Both have cell parts: nucleus, cell membrane, cytoplasm, etc. The organisms have more than one cell