Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Zoology Laboratory No. – 1Microscope One of the most important instrument that will use in biology laboratory . The "micro " word means small , the second word " scope " means something for looking with . Type of microscope : A- light ( compound ) microscope . B –dissecting microscope . C- flu recent microscope . D- electronic microscope . The compound microscope Uses tow sets of lenses , Ocular and objective . there are tow types of compound microscope according to number of ocular lenses : 1- monocular microscope (one ocular lens) 2- binocular microscope ( tow ocular lens ). Part of compound microscope : The microscope included four system : A- Supporting system 1- Base : the bottom portion on which the microscope rests . 2- Arm : curved part in which the microscope its carried . 3- Stage : a palate form on which slides to be studies are placed , the opening in the center allows light to passé from below through the object being examined . 4- mechanical stage: an adjustor knob below the stage move the stage forward and backward and from side to side . 5- Stage clip : tow clips mounted on the stage that hold slides in place . 6- Body tube : the portion that receive the ocular . B- Illumination system 1- Light : come from a lamp that fix into the base of the microscope . 2- Condenser : A lens located beneath the stage opining that controls the light – beam size . 3- Diaphragm : located beneath the stage , and function to regulated light intensity passing through the lenses. C- Adjustment system 1- Coarse adjustment knob : when turned ,and lower body tube or the Stage for focusing the microscope occurred . used with 4X and 10X. 2- Fine adjustment knob : usually found below or external the coarse adjustment knob , and used with high power or oil immersion lenses for fine or final focusing . D- Magnification system 1- Ocular lens (eye piece) : A removable lens at the tope of the body tube , marked 10X in most microscope . 2- Scanning objective lens : A lens marked 4X in most microscope . 3- Lower power objective lens : A lens marked 10X in most microscope . 4- High power objective lens: A lens marked 40X in microscope 5- Oil – immersion objective lens : A lens marked 100X in most microscope and distinguished by an colored circle – oil immersion called this because it look at the objective through a drop of oil ( cedar – wood oil ) . 6- Nosepiece : A plate usually circular , at the bottom of the body tube . 7- Revolving nosepiece : it is a movable part of the nosepiece that contain the various objective lenses . Magnification The magnification of the microscope is calculated by multiplying the magnification of the ocular lens by the magnification of the objective lens.