botany

• A microscope uses lenses to produce an enlarged, focused image of a specimen.
• The detailed structures in plant organs can be easily studied and understood using a microscope.
• The compound light microscope, which is used in Laboratory activities, uses two sets of lenses, the primary magnifiers, objectives; and the secondary magnifiers, eyepiece or ocular.
• The compound microscope is primarily composed of two main parts, mechanical and optical parts.
• The mechanical parts of a compound microscope include the base, pillar, arm, inclination joint, body tube, draw tube, revolving nosepiece, dust shield, and stage.
• The optical parts of a compound microscope include the eyepiece and objectives.
• Both eyes should be kept open when looking into the microscope, making sure that you already identified your “master eye”.
• The mirror is usually a double-sided face with concave and plain surface, used when the light source is at low and very bright intensity, respectively.
• A compound light microscope produces a magnified image of the object that shows all the detail structure and general appearance from which all observations are made.
• A compound light microscope is generally provided with three objectives: Low Power Objective (LPO), High Power Objective (HPO), and Oil Immersion Objective (OIO).
• The Oil Immersion Objective (OIO) is the longest cylinder with a small opening, attached in the microscope, used to observe fine details of specific parts with a very high magnification.
• The iris diaphragm should not be forced to the full limit in either direction when regulating its opening.
• The High Power Objective (HPO) is a longer cylinder with a smaller lens opening than LPO, used to obtain the detailed parts of the specimen with higher magnification.
• The Low Power Objective (LPO) is the shortest cylinder with a large lens opening and has lower magnification, used to obtain a large field of magnification and observe the general view of the specimen.
• The iris diaphragm is attached at the base of the sub-stage and provided with a lever or projecting handle, this can be manipulated to regulate the amount of light passing through the lenses.
• The proper care and handling of the microscope include holding it firmly with one hand on the arm while supporting the base with the other hand, carrying it in front of you with its side close to your body, not tampering with any parts of the microscope, not touching the lenses or mirror with fingers, using a cover glass when examining fresh mounts in water or any other fluids, and not inclining the microscope unless necessary.
• A drop of cedar oil (or other special immersion oil) on the slide with the specimen is needed when using the Oil Immersion Objective (OIO), thus, eliminating the refraction of light.
• The microscope should be returned in an upright position with LPO in place, body tube is lowered but objectives do not touch the condenser, diaphragm is wide open, stage clips are loosely set and the cover glass is in place.
• The condenser is a simple optical unit that fills the field of view with uniform illumination and supplies the objective with a cone of light at the right size to produce maximum result, it may be fixed or provided with adjustment for lowering and raising the condenser.