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MICROSCOPES & MAGNIFICATION. COMPOUND LIGHT MICROSCOPE:. USES LIGHT PASSING THROUGH THE SPECIMEN TO ENLARGE IT 2 LENSES OBJECTS APPEAR BACKWARDS & UPSIDE DOWN!. MICROSCOPE PARTS. FOCUSING:. NOT FOLLOWING FOCUSING PROCEDURES CAN SEVERLY DAMAGE THE MICROSCOPE &/OR SLIDE!
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COMPOUND LIGHT MICROSCOPE: • USES LIGHT PASSING THROUGH THE SPECIMEN TO ENLARGE IT • 2 LENSES • OBJECTS APPEAR BACKWARDS & UPSIDE DOWN!
FOCUSING: • NOT FOLLOWING FOCUSING PROCEDURES CAN SEVERLY DAMAGE THE MICROSCOPE &/OR SLIDE! • ALWAYS START WITH THE LOWEST MAGNIFICATION AND WORK UP TO A HIGHER MAGNIFICATION!
FOCUSING PROCEDURES: • PLACE THE SLIDE ON THE STAGE & CLIP IT IN TO SECURE • ADJUST THE DIAPHRAGM TO THE PROPER AMOUNT OF LIGHT • MAKE SURE YOU ARE ON THE LOWEST OBJECTIVE LENS • LOWER THE OBJECTIVE USING THE COARSE ADJUSTMENT KNOB
BRING THE SPECIMEN INTO FOCUS USING THE FINE ADJUSTMENT KNOB • CHANGE TO A HIGHER POWER OBJECTIVE • USE ONLY THE FINE ADJUSTMENT KNOB AT THIS POINT! • NEVER USE THE COARSE ADJUSTMENT AT HIGH POWER – YOU WILL BREAK THE SLIDE/LENS • WHEN DONE – STORE THE MICROSCOPES IN THEIR COVERS UNDER THE SINKS
MAKING A WET MOUNT SLIDE: • OBTAIN A CLEAN SLIDE & COVER SLIP • PLACE A SPECIMEN IN THE MIDDLE OF THE SLIDE (USE TWEEZERS) • WITH A DROPPER, PLACE ONE DROP OF LIQUID OVER THE SPECIMEN – DO NOT TOUCH THE DROPPER TO THE SPECIMEN! • HOLD THE COVER SLIP BY THE EDGES AT (WITH TWEEZERS) • LOWER IT SLOWLY ON AN ANGLE!
IF AIR BUBBLES ARE TRAPPED UNDER THE COVER SLIP, GENTLY TAP THE EDGE OF THE COVER SLIP WITH THE BLUNT END OF THE TWEEZERS • REMOVE EXCESS WATER WITH A PIECE OF PAPER TOWEL (TWEEZERS AGAIN, FOLKS) • PLACE THE SLIDE ON THE STAGE & VIEW!
MAKING A WET MOUNT STAIN: • MAKE A WET MOUNT SLIDE • USING A DROPPER, ADD A DROP OF STAIN ALONG THE EDGE OF THE COVERSLIP • TOUCH A PIECE OF PAPER TOWEL TO THE OTHER SIDE OF THE COVER SLIP TO DRAW THE STAIN THROUGH
MAGNIFICATION: • THE ABILITY TO MAKE IMAGES LARGER • RESOLUTION: THE SHARPNESS OR CLEARNESS OF AN OBJECT • TO CALCULATE TOTAL MAGNIFICATION: MULTIPLY THE MAGNIFYING POWER OF THE OBJECTIVE LENS x THE MAGNIFYING POWER OF THE OCULAR • OCULAR = 10x • LOW POWER LENS = 4x • TOTAL MAGNIFICATION = 40x
DISSECTING MICROSCOPE: • USED TO MAGNIFY 3 DIMENSIONAL SOLID OBJECTS (FOR DISSECTING) • OBJECTS APPEAR RIGHT SIDE UP AND NORMAL!!!! • NO SPECIAL SLIDES OR MOUNTS • ONLY 1 OBJECTIVE LENS – VERY LOW POWER
ELECTRON MICROSCOPE: • USES A BEAM OF HIGHLY ENERGETIC ELECTRONS TO EXAMINE OBJECTS ON A VERY FINE SCALE • CAN PRODUCE MAGNIFICATIONS OF MORE THAN 500,000 x THAT OF LIGHT! • ONE DISADVANTAGE IS THAT SAMPLES MUST BE VIEWED IN A VACUUM – SO NO LIVING SAMPLES CAN BE STUDIED!
TRANSMISSION ELECTRON MICROSCOPE SCANNING ELECTRON MICROSCOPE
E. COLI BACTERIA HEAD OF A SMALL BLACK ANT POLLEN