Science Cells Pt.1 (Sec1) Flashcards
Microscope + Protoplasm (52 cards)
How much can a light microscope enlarge a cell specimen?
up to 2000x
How much can an electron microscope enlarge a cell specimen?
to about 500 000X
What is the purpose of the arm in the light microscope?
To lift the microscope
What is the purpose of the base in the light microscope?
To provide stability and support for the microscope
What is the purpose of the eyepiece (ocular) in the light microscope?
Contains lenses to increase magnification of specimen
What is the purpose of the body tube in the light microscope?
To hole the eyepiece and objective lens at a distance from each other
What is the purpose of the condenser in the light microscope?
Located below the stage, to collect and focus the light from the light source onto the specimen
What is the purpose of the nosepiece in the light microscope?
Holds 3-4 objective lenses of different magnification and can be turned to switch from a low to a high-powered objective lens
What is the purpose of the objectives (objective lenses) in the light microscope?
They are lenses of different magnification, secured into place on a revolving nosepiece. The low powered objective lens is the shortest (4X-10X) and the high powered objective lens is the longest (40-60X)
What is the purpose of the diaphragm in the light microscope?
Located below the stage, allows adjusment of amount of light passing through the specimen by turning the lever
What is the purpose of the coarse adjustment knob in the light microscope?
A larger knob beside the body tube for focusing under low power. This knob can also be used to change the height of the stage.
What is the purpose of the fine adjustment knob in the light microscope?
A smaller knob for focusing under high power.
What is the purpose of the stage/stage clips in the light microscope?
Stage: Platform to hold slides in place
Stage clips: On the stage to secure the slides in position
What is the purpose of the light source in the light microscope?
Directs light through the opening in the stage to allow light to pass through the specimen
Step 1 to use the microscope
- Place the microscope on a bench, away from the edge before connecting ot the power source.
Step 2 to use the microscope
- Use the coarse adjustment knob to adjust the stage so that the objective lens will not be in contact with the stage when nosepiece is turned (may result in damage)
Step 5 to use the microscope
- Use the coarse adjustment knob to adjust the height of the stage until the object comes into focus
Step 3 to use the microscope
- Turn the nosepiece until the lowest power objective lense (4X) clicks into place
Step 4 to use the microscope
- Place the slide on the stage with the cover slip facing up. Secure with stage clips. Ensure that the specimen is in the middle of the opening of the stage and light can be seen passing through the specimen. Adjust the slide until the portion you wish to examine is in the centre of the field of view.
Step 6 to use the microscope
- Use the fine adjustment knob to make the image clearer and get the specimen to focus under high power
Step 7 to use the microscope
- Adjust the diaphragm to change the amount of light passing through the specimen to improve brightness of the image.
What are cells? (1)
Cells are the smallest unit of a living organism and can only be seen with a microscope.
Step 8 to use the microscope
- To use the higher power objective lens, adjust the stage to ensure that the lens does not come into contact with it. Turn the nosepiece to the required lens until the lens clicks into place.
What are the 3 parts of the cell theory?
- All organisms are composed of one or more cells
- Cells are the basic unit of living things
- All cells come from pre-existing cells.
