1 / 19

Cells: A Review

Cells: A Review A Little History. . . English scientist, Robert Hooke (1665) looked at cork through a compound microscope saw tiny, room-like structures called these structures 'cells' saw only outer walls - cork cells are not alive ( But they used to be! )

lotus
Télécharger la présentation

Cells: A Review

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cells: A Review

  2. A Little History. . . English scientist, Robert Hooke (1665) • looked at cork through a compound microscope • saw tiny, room-like structures • called these structures 'cells' • saw only outer walls - cork cells are not alive • (But they used to be!)

  3. Dutch fabric merchant and amateur scientist, Anton van Leeuwenhoek (1680) • looked at blood, rainwater, scrapings from teeth through a simple microscope • observed living cells • called these 'animalcules'

  4. German scientists • Matthias Schleiden (1838) • Said that plants are made of cells Schleiden • Theodor Schwann (1839) • Said that animals are • made of cells Schwann • Rudolph Virchow (1854) • Said that new cells form • when old cells divide. Virchow

  5. Cell Theory The work of Schleiden, Schwann and Virchow led to the development of the cell theory. • All living things are made of one or more cells. • Cells are the basic unit (building block) of all living things. • All cells come from cells that already exist.

  6. Unicellular or multicellular? Some complete organisms are made of only one cell. Some are made of only a few cells.

  7. Others are made of many cells.

  8. Parts of a Cell: All cells have some very basic parts. Cell Membrane - forms the outer boundary of the cell and allows only certain materials to move into or out of the cell

  9. Nucleus - directs the activity of a cell; it contains chromosomes made of DNA Nuclear Membrane - separates the nucleus from the rest of the cell

  10. Endoplasmic Reticulum - moves materials around in the cell (called ER for short) Golgi Bodies - are used for packaging and secreting; “hunks” of ER pinch off to form Golgi bodies

  11. Ribosomes - make protein for the cell

  12. Mitochondria - break down food and release energy to the cell

  13. Vacuoles - are storage areas for the cell exocytosis and endocytosis

  14. Lysosomes • The cell’s recyclers. • The garbage men of the cell.

  15. Cytoplasm - a gel-like material inside the cell that is made of water & nutrients

  16. We will look at these cells! Onion cells Cheek cells (stained) Elodea cells (plant)

  17. Microscopes micro = small + scope = to look Light Microscopes • 1. Simple • a. one lens • b. first invented in 1500’s • Compound • two lenses • We use this one in class.

  18. Electron Microscopes • TEM • Transmission electron microscopes • invented in 1931 • two dimensional image 2. SEM • Scanning electron microscopes • invented in 1981 • three dimensional image • May be referred to as “tunneling”

More Related