MOUNTING AND STAINING
Aim:
To prepare a temporary stained and mounted slide of a transverse section of a given stem and/or root.
Requirement:
Fresh or preserved material of stem and/or root, a sharp blade, microscope, slides, coverslips, watch glass, safranin (1gm in 100 ml of 50% ethanol), glycerin, brush, blotting paper.
Method for Taking Sections:
(a) Hold the plant material vertically between the thumb and index finger keep the edge of the razor at a right angle to the longitudinal axis of the plant material and cut thin sections.
(b) If the plant material is too thin or small to handle, it is fitted into a potato cube and then cut thin section with a sharp blade.
(c) Transfer these sections from the edge of the blade by touching the edge of the blade to watch glass containing water or with the help of a brush into a watch glass containing water.
Staining:
Staining is a process to stain or colour the components of cells or tissues in a section cutting. By staining, different components can be distinguished easily. The staining reagent is generally a colouring chemical that imparts colour.
Commonly used staining reagents are:
(a) Safranin: It imparts red colour to the lignified tissues present in plant cell walls and vessels.
(b) Glycerin: It is used in almost all slides. It is used as a clearing and hydrating agent. It prevents evaporation of water and drying of section cuttings. But when used along with water, lots of water droplets are seen under a microscope.
(c) Iodine: It imparts a blue colour to starch grains.
(d) Sudan red III: It dissolves the fixed oil present in seeds and impart red colour.
(e) Chloral hydrate: It is a clearing agent used for the removal of chlorophyll.
(f) Phloroglucinol: It stains lignified tissues to pinkish red.
(g) Ruthenium red: It stains mucilage to red colour.
Procedure for Staining:
(a) Select 3-4 good, thin and entire, transverse sections from watch glass containing water and transfer them with the help of a brush to another watch glass containing safranin stain.
(b) Allow the sections to remain in the stain for 2 to 3 minutes.
(c) After staining, wash the sections with water by transferring to another watch glass containing plain water to remove the extra stain.
Procedure for Mounting:
(a) Take a dean slide and place the stained section in the centre of the slide with the help of a brush, and mount in glycerin or water.
(b) Add one or two drops of water or glycerin on the section cutting so that the section cutting is submerged.
(c) Place the coverslip gradually with the help of a needle.
(d) If any air bubbles are seen, slightly lift the coverslip & add a drop of water and replace the coverslip till air bubbles are removed.
(e) Wipe off the excess glycerin or water from the sides of the coverslip with the help of blotting paper. Now, the stained and mounted slide is ready for observation under a microscope.
Precautions:
(i) The material and the razor/blade should be flooded with water while cutting the sections.
(ii) Brush should be used while handling the sections.
(iii) Coverslip should be placed gently to avoid the entry of air bubbles.
(iv) Remove extra glycerin with filter paper.
Remedial Biology Practicals
- Introduction to experiments in biology a) Study of Microscope b) Section cutting techniques c) Mounting and staining d) Permanent slide preparation 2. Study of cell and its inclusions 3. Study of Stem, Root, Leaf, seed, fruit, flower and their modifications 4. Detailed study of frog by using computer models 5. Microscopic study and identification of tissues pertinent to Stem, Root Leaf, seed, fruit and flower 6. Identification of bones 7. Determination of blood group 8. Determination of blood pressure 9. Determination of tidal volume
First Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise
First Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise
Suggested readings:
Recommended readings: