bioch5.txt

  1. cell theory
    All organisms are composed of one or more cells, within which the processes of life occur

    Cells are the smallest living things. Nothing smaller than a cell is considered alive

    Cells arise only by division of a previously existing cell. Although life likely evolved spontaneously in the environment of the early earth, biologists have concluded that no additional cells are originating spontaneously at present. Rather, life on earth represents a continuous line of descent from those early cells
  2. surface-to-volume ratio
    as cell size increases, volume grows much more rapidly than surface area
  3. plasma membrane
    lipid bilayer membrane encasing cells
  4. phospholipids
    • polar head w/ two non-polar tails
    • form the basic structure of the plasma membrane
  5. membrane proteins
    float within the lipid bilayer
  6. cell surface proteins
    act as markers to identify particular types of cells, or as beacons to bind specific hormones or proteins to the cell
  7. transmembrane proteins
    provide pasageways for ions and polar molecules to pass into and out of the cell
  8. prokaryotes
    • simplest cellular organisms; small, single-celled, most have cell wall and plasma membrane
    • no organelles
    • no nucleus
    • uniform cytoplasm (no subdivision)

    examples: bacteria and archaea
  9. flagellum
    long, threadlike structures, made of protein fibers that project from the surface of a cell

    used for feeding and locomotion
  10. pili
    small flagella
  11. organelle
    specialized structure within which particular cell processes occur
Author
aalford
ID
75938
Card Set
bioch5.txt
Description
Cell Theory and the Anatomy of the Cell
Updated