- Підготовка проб для мікроскопії в клітинній біології: основні підходи.
- Що таке мікротом?
3. MODULE № 3 "Genome storage system, reproduction and realization of genetic information"
Laboratory work № 3.1.
Purpose The Core Task Mikroskopiyuvaty preparations of animal tissue, human Theoretical information
The kernel implements two groups of common functions: one, associated with the storage of genetic information, the other - with its implementation, ensuring protein synthesis all prokaryotic cells is similar to eukaryotic nucleus, which is known as Nucleoid or nucleoplasm. Prokaryotic nucleoid can be attributed to the actual nuclear structure because it contains DNA. Nucleoid is clearly manifested in the light microscope after specific staining for DNA by Feulgen staining or fluorochromes. It can be observed using phase-contrast device in large bacteria or blue-green algae, as dark and more contrast formation in the middle of the cell. In ultrathin sections zone nukleoyda represented by thin loose network of fibrils 7.2 nm thick Nuclear apparatus of eukaryotic cells has several differences from prokaryotes. Firstly, DNA component is separated from the cytoplasm special membrane (nuclear envelope), and secondly, the amount of DNA in eukaryotic poison is thousands of times greater than in the nucleoid of bacteria, thirdly, the DNA of eukaryotes is a complex nucleoprotein complex forms special structure - chromatin, from which consist eukaryotic chromosomes. Then - in the nuclei of eukaryotes consists of several physically unrelated chromosomes, each of which contains one giant linear DNA molecule. Each chromosomal DNA is a polireplikonnu structure that contains sets replikuyuchyh autonomous areas. Synthesis and education transcripts of eukaryotic cells is accompanied secondary processes of adjustment, "mature", which include both fragmentation (processing), and splice some DNA fragments (splicing). Finally, the nuclei happens synthesis of proteins in eukaryotic cells that synthesis of DNA and RNA is separated from the process of protein synthesis
For staining of nuclei using basic colors - red (magenta core, safranin, tionin), blue (Victoria mitilenovyy blue), purple (hentsyan violet, crystal violet), and green - malachite green, methylene green), black (indulin).
Equipment, materials and methods. Microscope objective lenses, glasses with hole, glass rods, hinges, cover lenses. pipette graduated to 2 ml, 5 ml, 10 ml, Goryaev camera , test tubes, Petri dishes, flasks of 100 - 200 ml Mushrooms. Yeast, mold spores; higher plants. The order of performance and recommendations - Obtain samples of living cells and tissues. - Prepare for microscopy native (unpainted preparates) types "hanging drop" and "crushed drop." - Prepare smears and other preparations for painting. - Fix samples chemically and thermally - Conduct coloring technique. - These preparates microscopy. To fix the image on all available degrees of increase, from less to most. - Compare appearance of cells fixed and painted and native. - Set clear image of moving the condenser.
Control questions - Compare plant and animal cells. - Sub-cellular elements. - Preparation of samples for microscopy in cell biology: basic approaches. - What microtome?
- Dyes for micropreparations, staining, selectivity.