required practical - microscopes

Question 1

what are the 8 main labels on a microscope

Answer 1

eyepiece
eye lens
objective lens
stage
coarse focussing dial
fine focussing dial
lamp

Question 2

what is the equation for total magnification

Answer 2

magnification of eyepiece lens x magnification of objective lens

Question 3

what is the equation for calculating magnification

Answer 3

image size / actual size

Question 4

what is the actual size

Answer 4

real size of the object

Question 5

what is the image size

Answer 5

size that it appears to be after magnification

Question 6

how do you prepare an onion slide for a microscope

Answer 6

1. use a dropping pipette to add a drop of water to slide
2. separate a thin layer of onion
3. peel of a thin layer of epidermal tissue
4. use forceps to place on slide
5. ensure onion is flat
6. put two drops of iodine onto onion tissue
7. carefully place an over slip over the slide 8. use filter paper to soak up any extra liquid
8. put onto stage of microscope

Question 7

how do you view a prepared slide

Answer 7

1. place slide onto stage securing with clips
2. select lowest power objective lens
3. slowly turn coarse focussing dial to position the lens ensuring to view from the side and ensure that lens almost touches slide
4. use the fine focussing dial to bring cell into clear focus

Question 8

draw and label a microscope onion cell

Answer 8

include nucleus, cell wall, vacuole, cytoplasm