Morphological observations of yeast and experiments for the identification of dead and living cells
Morphological observations of yeast and experiments for the identification of dead and living cells
Yeast is a polymorphic, non-motile unicellular microorganisms, the nucleus and cytoplasm have been clearly differentiated, the body is larger than bacteria. Reproduction is also more complex, asexual reproduction is mainly germination, only fission yeast genus is to split the way to reproduce; sexual reproduction is through the splice to produce ascospores. In this experiment, we made water-immersion slices by staining with methylene blue and water-iodine water-immersion slices to observe the morphology of living yeasts and the way of budding reproduction.
Operation method
cellular identification
Principle
American blue is a non-toxic dye, its oxidized form is blue, and the reduced form is colorless, use it to dye the living cells of yeast, due to the role of metabolism in the cell, so that the cell has a strong reducing ability, can make the American blue from the blue oxidized form to the colorless reduced form, so that the living cells of the yeast are colorless, and for the dead cells or the old cells of the slow metabolism, due to their lack of such reducing ability or Reducing ability is very weak, and the blue or light blue stained by the blue. Therefore, it is not only possible to observe the morphology of yeast by using the aqueous immersion slice of methylene blue, but also to distinguish between dead and alive cells. However, the concentration and the time of the effect of the blue color have an effect, so attention should be paid to it.
Materials and Instruments
Saccharomyces cerevisiae Cal yeast Move 1. Observations on methylene blue immersion tablets(1) Add a drop of 0.1% Lüchner's Basic Blue Stain to the center of the slide. The drop should not be too much or too little, so as not to overflow or leave air bubbles when covering the coverslip. Then take a small amount of brewer's yeast cultured on bean sprout juice agar slant for 48 hours according to the aseptic operation method, and put it in Lü's basic beauty blue staining solution, so as to make the bacterium and the staining solution mix evenly.(2) Use tweezers to hold a piece of coverslip and carefully cover the droplet. When covering the piece, it should be noted that the coverslip should not be put down flat, but one side of the coverslip should be put in contact with the droplet first, and then the whole coverslip should be put down slowly, so as to avoid the production of air bubbles.(3) Leave the prepared water-soaked slides for 3 minutes and then examine them under the microscope. Observe with low magnification first, and then switch to high magnification to observe the morphology and budding of brewer's yeast, and at the same time, you can distinguish between dead and live cells according to whether they are stained with color or not.(4) Half an hour after staining, look again for an increase in the number of dead cells.(5) Repeat the above with 0.05% Lü's Basic Melloy Blue Stain.2. Water-iodine immersion tabletsPut a drop of iodine concentrate for Gram staining in the center of the slide, then add three drops of water on it, take a little bit of brewer's yeast and put it in the drop of water-iodine solution, make the bacterium mixed with the solution, cover the coverslip and then microscopically examine it. For more product details, please visit Aladdin Scientific website.
Melamine staining solution Iodine solution
Microscope Slide Coverslip