Cell Theory & Biological Structure

I. History

A. Reductionism: break apart a complex structure into its component parts and reduce it to the smallest component, which in this case refers to the smallest living unit

  1. Assimilate E from environment
  2. Maintain itself
  3. Grow and replicate
  4. Evolve or change over time

B. Cell comes from cella ‘small room’ Hooke 1665 structure of cork

C. Schleiden 1804-1881

  1. Recognized that all plants and animals were comprised of cells
  2. Nucleus seen as a separate sub-cellular component

D. Schwann 1810-1882

  1. Completed analogy between plants and animals
  2. A three part conclusion
  1. a. entire organism composed of cells or substances secreted by them
  2. b. the cell has its own life
  3. c. the life of individual cells is subject to the living organism as a whole

3.Metabolism

  1. anabolism — building up of cells
  2. katabolism — breaking down

E. Virchow 1858

  1. "Omnis cellula e cellula"
  2. Siebold: "Omne vivum ex ovo"
  3. Pasteur "Omne vivum e vivo"

II.Biological hierarchy in animals and plants

A. cell to organism

B. Organismal structure

1. Organism types

2. Organ systems

  1. nervous
  2. circulatory
  3. digestive
  4. muscular
  5. respiration
  6. skeletal

C. Ecological hierarchy: organism to ecosystem

A. Eukaryotic cell structure

1. subcellular organelles

  1. nucleus
  2. mitochomdria
  3. chloroplasts
  4. endoplasmic reticulum
  5. golgi apparatus
  6. liposomes

2. recognition of DNA associated with membrane-enclosed plastids leads to endosymbiosis theory

IV. Prokaryotic cell structure

  1. The bacterial cell wall. ©2000 Timothy Paustian, University of Wisconins-Madison.

V. Endosymbiosis Hypothesis

Web Resources

update14 September 2000