Observation experiments on the basic morphology of animal cells
Observation experiments on the basic morphology of animal cells
Regardless of the shape of the cell, the structure of a cell is generally divided into three main parts: the cell membrane, the cytoplasm, and the nucleus. However, there are exceptions. For example, the nucleus disappears when mammalian erythrocytes mature.
Operation method
basic program
Principle
The correlation between the morphology and structure of cells and their functions is a common feature of many cells, and it is more obvious in the more differentiated cells, and this rationality is formed by the long evolutionary process of organisms. For example, muscle cells with the function of contraction are elongated; nerve cells with the function of sensing stimuli and transmitting impulses have dendritic projections of varying lengths; and free blood cells are round, oval, or pie-shaped.
Materials and Instruments
Toadstool Human Blood Move 1. Preparation of pressurized slices of toad spinal cord for observation of motor nerve cells in the anterior horn of the spinal cord. For more product details, please visit Aladdin Scientific website.
Toluidine blue, methyl blue, Ringer's solution.
Microscope Slides Coverslips Surgical Equipment Dissecting Trays Microscope Micrometers
(1) Take a toad, destroy the brain and spinal cord, cut off the head at the cleft of the mouth, remove the medulla oblongata, cut open the vertebral canal, and see the milky spinal cord; remove the spinal cord and place it in a flat dish, wash off the blood with Ringer's solution and place it on a carrier plate, and cut it up.
(2) Press another carrier sheet over the fragmented spinal cord and squeeze firmly.
(3) Remove the upper carrier sheet to obtain a compressed sheet.
(4) Place a drop of toluidine blue dye on the slide and stain for 10 minutes, cover the slide and aspirate the excess dye.
(5) Under the microscope, the darker stained small cells are glial cells.
(6) The large, large cells with multiple protrusions that stain an orchid purple color are spinal cord anterior horn motor nerve cells, with triangular or star-shaped cytosol and a round nucleus in the center containing a nucleolus.
2. Stripping and observation of toad skeletal muscle cells
(1) Cut the skin of the toad's leg and cut out a small piece of muscle and place it on a carrier sheet.
(2) Use forceps and a dissecting needle to peel the muscle mass to become a muscle bundle, and continue peeling to obtain very fine muscle fibers (myoblasts).
(3) Straighten the muscle fibers as much as possible.
(4) Under the microscope, the myocytes are elongated, with visible transverse stripes of varying refraction, and each myocyte has multiple nuclei distributed around the periphery of the cell.
3. Preparation and observation of pressed tablets of toad liver
(1) Cut open the abdominal cavity of the toad, take a small piece (about 2~3 mm3 ) of liver and place it in a flat dish, wash it with Ringer's solution, and squeeze the blood out of the liver by gentle pressure with forceps.
(2) Then put it on the carrier plate, and the method of preparation is the same as that of spinal cord pressure plate.
(3) Staining was done with methyl orchid, and under the microscope, the nuclei of hepatocytes were stained with orchid color, and the hepatocytes were tightly arranged and squeezed into polygonal shape.
4. Preparation and observation of toad blood smears
(1) Take a drop of toad's blood and place it near one end on a carrier plate.
(2) Hold one end of another carrier sheet at an angle of 45° against the leading edge of the drop of blood and push it forward with even pressure, so that the blood forms a uniform thin layer on the carrier sheet, and allow it to dry.
(3) Microscopic observation shows that the toad red blood cells are ellipsoidal and nucleated.
(4) The white blood cells are few in number and round. 
Figure 1-1 Preparation of blood smears
5. Preparation and observation of human blood smears
(1) Take a drop of human blood and prepare it as above.
(2) The human erythrocytes were observed microscopically as concave discs without nuclei.
(3) The number of self-cells is small and round.
6. Preparation and observation of human oral epithelial cell specimens
(1) Use a toothpick to scrape oral epithelial cells and apply them evenly on the carrier sheet (do not repeat the frothing).
(2) Apply a drop of toluidine blue staining solution, stain for 5 minutes, cover the slide and aspirate the excess stain.
(3) Under the microscope, the epithelial cells on the surface of the duplicate oral cavity are seen to be flat and oval, with an oval nucleus in the center, and stained with an orchid color.