Cell Theory

• Cell:

  • Basic membrane-bound unit that contains fundamental molecules of life
  • Smallest living organism and basic unit of life on earth
• Cell Biology:

  • Focuses on the study of cells, their structure, function, and life processes
  • Involves examination and analysis of cells, including organelles and other cellular components
• Microscope:

  • Optical instrument used to magnify and observe objects too small to be seen with the naked eye
  • Enables study of tiny structures like cells, microorganisms, and small particles
• Spontaneous Generation:

  • Process by which living organisms develop from nonliving matter
  • Louis Pasteur disproved this theory and proposed "life only comes from life"
• Robert Hooke (1665):

  • Observed box-shaped structures in cork, named them "cellula" or small rooms
  • Published Micrographia, a book with drawings and descriptions of organisms viewed under the microscope
• Antonie van Leeuwenhoek (1676):

  • Discovered bacteria and protozoa, called them "animalcules"
  • First person to observe living cells
  • Father of Microbiology
• Matthias Jakob Schleiden (1838):

  • Proposed that the basic unit of all plant tissues was the cell
  • Concluded that plant structures were composed of individual cells or aggregates of cells
• Theodor Schwann (1839):

  • Proposed that all living organisms are composed of cells
  • Cell is the basic unit of structure and function in animals and plants
• Rudolf Virchow (1858):

  • Proposed "omnis cellula e cellula" (All cells come from pre-existing cells)
  • German physician, pathologist, and anthropologist
• Cell Theory:

  • Fundamental scientific theory stating that cells are the basic units of all living tissues
  • All living organisms are composed of cells
  • Cells are the basic unit of life
  • Cells come from pre-existing cells
  • Genetic material is contained in cells
  • Energy flow occurs within cells
  • Cells of all organisms within a similar species are mostly the same structurally and chemically