For Mad House

The outline of the cell theory states that:
  • All organisms are composed of one or more cells.
  • Cells are the smallest units of life.
  • All cells come from pre- existing cells.

Evidence of the Cell theory comes from the research and work of many other scientists.
Robert Hooke:

  • was an English natural philosopher.
  • 1st observed cork cells in 1665 with a microscope he built himself.
  • NOTE: Robert Hooke did not invent the microscope, he just improved it.*

Matthias Jakob Schleiden:

  • was a German botanist
  • Through his observations, he stated that different parts of plants are composed of cells.

Antonie Van Leevwenhoek:
  • Observed singular cellular organisms.
    - he called the "animalcules" meaning "little animals"

Teddy Schwann:
  • An early 1800 German scientist, specifically a zoologist.
  • Through his observations, he stated that animals are also made up of many cells.

Louis Pasteur:

  • 1860's French chemist & microbiologist.
  • Debunked the 'spontaneous generation' idea.
  • Stated that "living things come from living things".

Unicellular organisms carry out all the functions of life. (Metabolism, response, homeostatis, growth, reproduction, nutrition.)

Compared relitive sizes of molecules, cell membrane thickness, viruses, bacteria, orgenells, and cells, in the appropriate SI unit.

  1. Molecules (1 nm)
  2. Cell membrane thickness (10 nm)
  3. Viruses (100 nm)
  4. Bacteria (1 µm)
  5. Organelles (less than 10 µm)
  6. Most cells (less than 100 µm)

Calculating the linear magnification of drawings and the actual size of specimens in images of known magnification:
Magnification = Measured Size of Diagram ÷ Actual Size of Object

Chris Bland work
Diagram of liver cell

external image CE116800FG0010.gif

Diagram of e.coli

external image cell-ecoli.gif
Eukaryotic vs. Prokaryotic cells
The prokaryotes are a group of organisms that lack a cell nucleus, or any other membrane-bound organelles.
Most are unicellular, but a few prokaryotes such as myxobacteria have multicellular stages in their life cycles.[[#cite_note-0|[]]

A distinction between prokaryotes and eukaryotes (is that eukaryotes do have "true" nuclei containing their DNA, whereas the genetic material in prokaryotes is not membrane-bound. Eukaryotic organisms may be unicellular, as in amoebae, or multicellular, as in plants and humans. The difference between the structure of prokaryotes and eukaryotes is so great that it is sometimes considered to be the most important distinction among groups of organisms

Three differences between plant and animal cells

three things that are in plant cells but not animal cells

  • A large central vacuole, a water-filled volume enclosed by a membrane known as the tonoplastmaintains the cell's turgor, controls movement of molecules between the cytosol and sap, stores useful material and digests waste proteins and organelles.
  • A cell wall composed of cellulose and hemicellulose, pectin and in many cases lignin, and secreted by the protoplast on the outside of the cell membrane. This contrasts with the cell walls of fungi (which are made of chitin), and of bacteria, which are made of peptidoglycan.

  • Unlike animal cells, plant cells are stationary.
two roles of extracellular components.

the making and developing of plant cell wall and glycoproteins

Structure of membranes

external image plasmamembranefigure1.jpg

Hydrophilic molecules and hydrophobic molecules form a double layer with the hydrophilic heads on the outside of the membrane while the hydrophobic tails are in the inside of the membrane. The heads are attracted to the water around making the membrane stable.

Membrane proteins functions:

  • pumps for active transport
  • has hormone binding sites
  • are electron carriers
  • have the channels for passive transport
  • enzymes catalyze reactions

Diffusion is the movement of particles between different concentration gradients across the protein membrane

Osmosis the movement of water across the permeable membrane; passive transport