Introduction to the Microscope  Care  Parts  Focusing

Why Microscopes? Why do we need microscopes? –To “see” what we can’t see with the naked eye. –Here are a few examples….

HIV (red) on a white blood cell (green) HIV is short for: Human Immunodeficiency Virus It is the virus that causes AIDS. There are dozens attacking this human white blood cell.

Seeds (yellow) on the surface of a strawberry (red)

E. Coli (brown) and viruses (blue) attacking E. Coli is a kind of bacteria that can make us sick, but also lives in our stomach. Bacteria are single- celled organisms. Viruses are not considered alive, and are NOT made of cells.

Salt (left) and pepper (right)

Protozoan Protozoans are single-celled organisms found usually in water (most do not live in drinking water). Malaria is caused by a protozoan.

Human eyelashes (green) and skin Notice how flaky the human skin is. It is constantly flaking off (sloughing) and being replaced from below.

Blood clot crystals (scabs!) These crystals are only one component of a blood clot.

Bee stinger

Needle and thread

Magnification – making the object bigger Resolution – how clearly you can see the object copio/dswmedia/simula/esimula1.htmlhttp://brunelleschi.imss.fi.it/esplora/micros copio/dswmedia/simula/esimula1.html

Light because we use light to see the images Compound because it uses two lenses to view a specimen.

Light vs. Electron

Eyepiece or Ocular Lens Body Tube Revolving Nosepiece Arm Objective Lenses Stage Stage Clips Coarse Focus Fine Focus Base Diaphragm Light

Eyepiece or Ocular Lens Body Tube Revolving Nosepiece Arm Objective Lenses Stage Stage Clips Coarse Focus Fine Focus Base Diaphragm Light Where you look to see image – magnifies 10x Holds eyepiece Rotates and holds objective lenses Low 4x, Medium 10x, High 40x Used to carry microscope For low power lens – always start here! Fine tuning for higher power lenses Hold slide in place Controls amount of light Makes specimen easier to see Supports the microscope Where slide is placed for viewing

Always carry with 2 hands, one on the arm and the other on the base Only use lens paper for cleaning and don’t touch the lenses to anything (including your finger.) Always store covered Don’t let cords hang where the microscope could be pulled off the table When finished, wrap cord around base

Ocular lens times the objective lens If the ocular lens is 10x and the objective lens is 5x, the total magnification would be: 50! Our ocular lens magnifies 10x. Our objective lenses are 4x, 10x, and 40x. That means we can magnify 40x, 100x, and 400x

Place a slide on the microscope Use stage clips only when you are sure you don’t want to move the slide around Click nosepiece to the lowest (shortest lens) setting Start with the objective closest to the specimen Use the coarse focus to move objective AWAY from specimen

Have slide focused on low power first Click the nosepiece to the next biggest objective lens Do NOT use the coarse focusing knob Use the fine focus knob Do NOT force any knobs They should all move easily Do NOT turn the fine focus more than a full turn Start over on low power if you can’t see specimen

Onion Cells

Cheek Cells

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Mosquito Image 2 Image 1

Mosquito Stapled Paper Image 1 Image 2

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Black Widow Spider Claw Image 3 Image 4

Black Widow Spider Claw Mascara Brush Image 3 Image 4