microscopy

Question 1

what are eyepiece graticules and stage micrometers used for?

Answer 1

measurement of action sizes of cells/tissues when viewed using a light microscope

Question 2

eyepiece graticule

Answer 2

a circular piece of glass/plastic sitting on a ledge in the eyepiece with a scale engraved.
will always appear in full

Question 3

stage micrometer

Answer 3

a slide with a very accurate scale engraved on the glass, placed on the stage of the microscope.
they come in varying lengths (2mm and 0.01mm)

Question 4

method of calibration of the eyepiece graticule

Answer 4

use both eyepiece graticule and micrometer at same time, rotating eyepiece graticule by turning the eyepiece. move stage so alignment between eyepiece and micrometer
calculate scale

Question 5

serial dilution

Answer 5

where the concentration of a solution decrease by the same amount each time

Question 6

calculation of dilution factor

Answer 6

division of initial volume by final volume

Question 7

test for proteins

Answer 7

biuret test
sample added to biuret solution and gently heated
colour change from blue to lilac

Question 8

starch test

Answer 8

add iodine to ample

colour change from orange to black

Question 9

lipids test

Answer 9

shake sample with ethanol until dissolves, mix with water and solution will turn into a cloudy white emulsion

Question 10

test for reducing sugars

Answer 10

add benedicts solution and put in water bath

will turn red

Question 11

test for non-reducing sugars

Answer 11

boil sample with dilute HCl, cool and neutralise before adding benedicts solution and putting in water bath
will turn red`

Question 12

chromatic aberration

Answer 12

production of images with light split into different colour