Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Extracellular matrix wikipedia , lookup
Cytokinesis wikipedia , lookup
Cell growth wikipedia , lookup
Tissue engineering wikipedia , lookup
Cell encapsulation wikipedia , lookup
Cell culture wikipedia , lookup
Cellular differentiation wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
CELLS Smallest unit of life that can carry out all the functions of an organism. History of the Cell: • 1665 – Robert Hooke discovered and described the fundamental unit of all living things (cells) by using thin slices of cork. • He gave the tiny chambers the name “cell” because it reminded him of a monastery's tiny room which were known as cells. History of the Cell: • 1674 – Anton Van Leeuwenhoek (“Father of Microbiology”) was the first man to witness a live cell under a microscope. • He made many different types of single lens microscopes that could magnify up to 300 X. • When observing pond water, he discovered tiny organisms he called "animalcules.” History of the Cell: History of the Cell: • 1838: Matthias Schleiden (Botanist) concluded that all plants are made out of cells. History of the Cell: • 1839: Theodor Schwann (Zoologist) concluded that ALL organisms including animals are made up of cells. History of the Cell: • 1855: Rudolph Virchow (Doctor) – proposed that all cells arise from existing cells. – Until 1855: Schleiden and Schwann believed that cells might “crystallize out” from fluids. These discoveries, confirmed by other biologists, are summarized in the CELL THEORY What is the Cell Theory? A fundamental concept in biology that states: 1. Cells are the basic units of life (Hooke) 2. All organisms are made of cells (Schleiden &Schwann) 3. All cells come from existing (other) cells (Virchow) Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell Part of the Microscope Parts of the Microscope A. Occular (eye piece) B. Body Tube C. Revolving Nosepiece D. Objective Lenses E. Stage F. Diaphragm (controls amount of light) Parts of the Microscope G. Light source H. Base I. Fine Adjustment knob J. Coarse Adjustment Knob K. Stage Clips (holds slides) L. Arm Carrying a Microscope Magnification increases the apparent size of a specimen when you view it through the microscope. Calculating Magnification Magnification of objective lens X occular lens magnification Since microscopes magnify cells we have a new unit of measurement. These new units are called microns. 1mm 1 1000 = 1000 µm = 1 µm We can use microscopes to estimate the size of cells we are looking at. Example a)if the Field fieldof view of view = 1mm Onion cell 1mm (1000 µm) then0.5onion cells are ______________ mm 500 microns or ______________(µm) in length b)if the field of view = 0.5mm or 500µm then these cheek cells would be 500 5 100 µm in length mm or ______________ 0.5 mm (500 µm) Human cheek cell