Unit 1: Cells and proteins KA1.1: Laboratory techniques for biologists

Question 1

what are some hazards that might be encountered in the lab

Answer 1

-toxic chemicals
-corrosive chemicals
-heat and flammable substances
-pathogenic organisms
-mechanical equipment

Question 2

name 3 kinds of control measures that could be used in the lab

Answer 2

-appropriate handling and disposal techniques
-protective clothing and equipment (PPE)
-aseptic technique in microbiology

Question 3

what is the purpose of a risk assessment

Answer 3

to outline all the hazards and possible control methods to minimise the risk

Question 4

what is a linear dilution

Answer 4

dilutions that differ by an equal interval

Question 5

what is a log dilution

Answer 5

dilutions that differ by constant proportion

Question 6

what is colorimetry used for

Answer 6

finds the concentration of a known solute in a coloured solution or the turbidity

Question 7

what is the equipment used in a colorimetry experiment

Answer 7

colourimeter, curvette and coloured solution

Question 8

what is the set up for a colourimetry experiment

Answer 8

-pick wavelength of light most absorbed by the colour of the solution (opposite on colour wheel).
-machine needs to be calibrated using a blank of only the solvent baseline (negative control)

Question 9

what is a colourimetry experiment goof for

Answer 9

estimating the density of cells or estimating the concentration of solutions

Question 10

define the term buffer

Answer 10

a solution where adding acids or alkalis have a very small effects on the pH

Question 11

what does adding a buffer solution allow

Answer 11

this allows pH in a reaction mixture to be kept constant.

this is extremely useful for biological reactions as pH can effect protein and thus the overall reactions

Question 12

what does centrifugation separate molecules by

Answer 12

density

Question 13

what does thin layer chromatography separate molecules by

Answer 13

solubility

Question 14

what does affinity chromatography separate molecules by

Answer 14

affinity (no way 😧)