Foundations in Biology

Main components of the cell theory.

    1. The cell is the structural unit of life

    2. All organisms are composed of one or more cells

    3. cells can only arise by division of pre-existing cell

    1940’s - discovery of DNA as genetic material led to fourth

    4. Cells contain genetic information in the form of DNA and that information is passed from     parent to daughter cell

Explain how the first cell originated

    the first cell origin was thought to have come from spontaneous generation

        -disproved by Pasteur with the swan neck experiment

               -he determined that life cannot be spontaneously generated in a sterile medium

               -once this was disproved came biogenesis

        -biogenesis - the hypothesis that living matter arises only from other living matter.

Very first cell came from…

        need to go back in time to look at the first cell

            this was done with fossil records to find ancestor of all cells

            problem that the rocks on this planet arent as old and recycled

                need to go back to understand the origin

            Earth is 4.54 BYA

    know that first prokaryotic fossil found 3.7 to 3.5 BYA

        simple cells

        on their own until eukaryotic cells developed

    Not the first eukaryotic fossil found 1.5 BYA

        but rather the first evolved

Explore the origin of life by predicting early earth condition and recreating to understand. Leads to the following experiement

A. Miller-Urey Experiment

-Ingredients for life is organic molecules

    -must be source of org mol

how we can synthesize from inorganic molecules

org molecule are backbone for life

Possible natural chem process that lead to life

    -1920’s Oparin & Haldane

        -hypothesized that chem in early atmosphere fueled by sunlight would spontaneously create org molecules

    -1950s’s Miller-Urey experiment aka prebiotic soup

        -with the use of organic spark turned brown w amino acids and other complex organic molecules

        -proved

B. Formation of protocells and the first cells

    -autocatalytic reacts

        leads to self replication of biomolecules

                thus leads to formation of polymers and increase concentration of biomolecules aka                 coacervates

    -gain of metabolism

    -gains information (RNA to DNA)

    -Membrane encapsulates coacervates

        -protocells // increases complexity


Evolution of eukaryotic cells (earliest was that 1.5 BYA)


    

  • List the fundamental properties shared by all cells. Describe the importance of each of these properties.

  • Contrast the structure and function of proteins, nucleic acids, polysaccharides, and phospholipids.

  • Illustrate the structures of eukaryotic and prokaryotic cells.

  • Compare prokaryotic and eukaryotic cells.

  • Explain the factors that limit cell size and how the eukaryotic cells partially adapted to overcome them.

  • Summarize the main models used in cell and molecular biology research.