| Question | Answer |
| clean the microscope | use only special grit-free lens paper to clean the lenses. use circular motion to wipe lenses. clean before and after use |
| begin focusing process | with the lowest powered objective lens in position changing to the higher-power lenses as necessary |
| use coarse adjustment knob | only with the lowest power objective lens |
| coverslip | always use w wet mount preparations |
| remove parts? | never remove parts from the microscope. inform your instructor of any mechanical problems that arise |
| storing | remove the slide from the the stage, rotate the lowest power objective lens into position, wrap the cord neatly around the base and replace dust cover n return microscope to cabinet |
| microscope | instrument of magnification |
| magnification is achieved | through the interplay of two lenses---the ocular lens and the objective lens |
| objective lens | magnifies the specimen to pro duce a real image that is projected to the ocular. |
| real image | projected to the ocular |
| virtural image | magnified image that your eyes see |
| total magnification (TM) | equal to the power of the ocular lens multiplied by the power of the objective lens used. ex 10 x 45 equals 450 TM or 10 x 45 TM |
| resolution | the ability to discriminate two close objects as separate |
| base | bottom of the ms. provides a sturdy flat surface to support and steady the ms |
| substage light | located in the base. the light from the lamp passes directly upwardthrough the ms |
| light control knob | located on the base or arm. this dial allows u to adjust the intensity of the light passing through the specimen |
| stage | the platform that the slide rests on while being viewed. the stage has a hole in it to allow light to pass through the stage and through the specimen |
| mechanical stage | holds the slide in position for viewing and has two adjustable knobs that control the precise movement of the slide |
| condenser | small nonmagnifying lens located beneath the stage that concentrates the light on the specimen. may have a light that raises n lowers to vary the light |
| condenser | best position is close to the inferior surface of the stage |
| iris diaphragm lever | a shutter in the condenser that can be controled by a lever to adjust the the amount of light passing through the condensor |
| iris diaphragm lever | can be moved to close the diaphragm and improve contrast. |
| iris diaphragm lever | if your field of view is too dark, you can open the diaphragm to let more light in |
| coarse adjustment knob | allows u to make large adjustments to the height of the stage to initally focus focus your specimen |
| fine adjustment knob | used for precise focusing once the initial coarse focusing has been completed |
| head | attaches to the nosepiece to support the objevtive lens system. it also provides for attachment of the eyepieces which house the ocular lens |
| arm | vertical portion of the ms that connects the base to the head. |
| nosepiece | rotating mechanism connected to the head |
| nosepiece | carries three or four objective lenses and permits positioning of the lenses over the hole in the stage |
| objective lenses | lenses are attached to the nosepiece. |
| compound microscope | has four objective lenses scanning 4x, low power 10x, high power 40x, oil immersion 100x |
| ocular lens (es) | binocular ms will have two lenses located in the eyepiece at the superior end of the head |
| ocular lenses | most have a magnification power of 10x |
| parafocal | ms feature most lab ms's have. the slide should be in focus (or nearly so) at the higher magnifications once you have properly focused at the lower magnification |
| field | the area u see through the ms |
| working distance | how far is the bottom of the objective lens from the surface of the slide. |
| ms field | decreases with increasing magnification |
| lens for storage | rotate the lowest powered objective lens into position |
| beginning to focus | use the lowest power of lens |
| virtual image | the enlarged image u see |
| resolution | (resolving power) the ability to discriminate two close objects as separate |
| working distance | the distance from the bottom of the objective lens to the surface of the slide |
| field | the area of the slide seen when looking through the microscope |
| parafocal | after focussing in low power, you only need to use the fine adjustment to focus at the higher powers |
| prepare a wet mount | a) place the object in a drop of water (or saline) on a clean slide b) hold a coverslip at a 45 degree angle w the fingertips; and c) lower the coverslip slowly |
