Biology 11 Review

Botany Exercise 1 – Microscopy
A. The Compound Microscope  microscope – optical instrument consisting of a system of specially ground lenses that gives sharp, distinct, and highly magnified images of minute objects.  compound microscope will be used. o two lenses: eyepiece + objective lenses o inverted image

base coarse adjustment knob fine adjustment knob revolving nosepiece objective lenses stage stage clips stage opening condenser iris diaphragm mirror

 U-shaped platform that supports the entire microscope  moves the tube toward/away from the specimen for focus  tunes the focus the increase the details of the specimen  switches objectives  magnifies the specimen viewed  LPO: 10x; HPO 43x  platform where slide is placed  holds slide in place  enables light to pass through  gathers and focuses light  adjusts amount of light  reflects light from external source

How does the image move in the field of view, in realtion to the movement of the slide? opposite if slide is moved L [up], image moves R [down]

What can you deduce about the path of light in the body tube? light is refracted through the lenses resulting in a inverted image

Is the position of the object in the field changed by shifting from LPO to HPO? Why?
No, because the microscope is parcentral parcentral = same center parfocal = same focus

Is there a decrease or an increase in the area of specimen seen in the field of vision changing from LPO to HPO?
Decrease; larger magnification with constant field of vision lenses provide leads to viewing a more magnified part but of a smaller area.

B. The Dissecting Microscope  singe lens  magnification: 6x or 20x  study of large and thick specimens [small organisms and parts of large organisms]  erect image

How is the movement of the slide related to that of the image? Why? same; one lens if slide is moved L [up], image moves L [up] C. Calibration of the Micrometer Eyepiece  necessary because length set of each scale