Cell Bio Report 2

Experiment 3 Title : Cell Structure 1 Objective : I.

To prepare specimens for staining.

II.

To identify unique and standard structures of the microscopic world.

III.

To identify and use different stains for the different types o f organelle.

Introduction : Cells were first described in 1665 by Robert Hooke. He examined (under a coarse, compound microscope) very thin slices of cork and saw a multitude of tiny pores that he r emarked looked like the walled compartments a monk would live in. Hooke’s description Hooke’s description of these cells (which were actually nonliving cell walls) was published in Micrographia. His cell observations gave no indication of the nucleus the nucleus and other organelles other organelles found in most living cells. The first man to witness a live cell under a microscope was Antony van Leeuwenhoek. Leeuwenhoek probably also saw bacteria. saw bacteria. Cell  Cell theory was in contrast to the vitalism the vitalism theories proposed before the discovery of cells. The o bservations of Hooke, Leeuwenhoek, Schleiden, Schwann, Virchow, and others led to the development of the cell c ell theory. The cell theory is a widely accepte d explanation of the relationship between cells and living things. The cell theory states:   

All living things or organisms are made of cells and their products. New cells are created by old cells dividing into two. Cells are the basic building units of life.

Eosin is a fluorescent red dye red dye resulting from the action of  bromine  bromine on fluorescein. on fluorescein.   It can be used to stain cytoplasm, stain cytoplasm, collagen  collagen and muscle and muscle fibers for examination under the microscope. the microscope. Structures  Structures that stain readily with eosin are termed eosinophilic. termed eosinophilic. Eosin  Eosin also stains red stains red blood cells intensely red. The cotton blue lactophenol is the most common method of staining fungi. The dye will penetrate the hyphae and reproductive cells in the fungi. Plant chromosomes uses acetocarmin stain, a 1 % solution of carmine in 45 % acetic acid is used. Freshly fixed material is transferred into 1 % acetocarmine for at least 30 min and then analyzed by the squash method. If the material was fixed for a longer time, it requires a longer staining time to reach good contrast. Iodine is used as a starch indicator. When in solution, starch and iodine turn a dark blue colour. After staining cells and preparing slides, they may be stored in the dark and possibly refrigerated to preserve the stained slide, and then observed with a microscope. Noland’s solution is a staining that shows blue colour which can stain flagellum.

Results :

1} Upper surface of Rheo discolours with eosin

Drawing

2} Upper surface of Rheo discolours without eosin

Drawing