Microscopes

• stage- Where the slide is clipped down
• objective lens- the part that changes the magnificaton of the image
• Eyepiece lens- Where the viewer looks through to se the specimen
• coarse focus- moves the stage upp and dow
• mirror- reflect the light onto the stage
• fine focus- used to make the image clearer
• image size = actual size *magnification
• A microscope has a top eyepiece for viewing, a course focus knob, a fine focus knob, and objective lenses.
• The eyepiece on a microscope has a magnification of times ten.
• The objective lenses on a microscope can have a magnification of times four, times ten, or times 40.
• To view cells under a microscope, a glass microscope slide is needed.
• Onions are a common cell type to view under a microscope because the layers of the onion peel away easily.
• To view onion cells under a microscope, a layer of onion cells is peeled off and placed onto a glass microscope slide with tweezers, being careful to keep it as flat as possible.
• Dye is added to the onion cells to give color to the different parts of the cell, making it easier to see.
• The parts found in both onion cells and cheek cells are labeled in blue.
• Onion cells and cheek cells are examples of cells that can be observed under a microscope.
• The magnification of a microscope is calculated by multiplying the IPS the eyepiece lens magnification times the objective lens magnification.
• The fine focus is used to get a very sharp image of the cells.
• The smallest objective lens, x for objective lens, is used in the microscope.
• The stage of the microscope is placed onto the stage very carefully.
• The parts found in onion cells only are labeled in green.
• The course focus is used to bring the stage up as far as it will go.
• More magnification can be achieved by changing the objective lens to one with more magnification and using the fine focus to get a sharp image.
• A coverslip, a very thin and delicate piece of glass, is placed over the onion cells to keep them flat and prevent them from breaking.
• The onion cells are placed under a microscope on the stage, and the microscope is ready for viewing.