Tests

Question 1

What is the test for proteins?

Answer 1

Biuret.
Blue to purple

Question 2

Test for lipids?

Answer 2

Emulsion test.
2cm of sample. 5cm of ethanol.
Shake.
Add 5cm of water.
Shake.
Milky white emulsion.

Question 3

Test for starch?

Answer 3

Iodine.
Shake.
Orange to blue/black

Question 4

Test for reducing sugars?

Answer 4

Add 2cm of sample. 2cm of Benedicts. Filter.
Water bath for 5 min.
Blue to brick red if high conc

Question 5

Test for non reducing sugars?

Answer 5

Add 2cm of sample to 2cm of dilute hydrochloric acid. Water bath for 5 min.
Add sodium hydrogencarbonate.
Retest with 2cm of Benedicts. Water bath.
Colour change

Question 6

What are some reducing sugars?

Answer 6

Galactose
Glucose
Fructose
Maltose

Question 7

Example of a non reducing sugar

Answer 7

Sucrose.

Question 8

Why does benedicts produce a coloured precipitate?

Answer 8

Copper II sulfate in benedicts is reduced to copper II oxide which is insoluble.

Question 9

What is the ELISA test?

Answer 9

Enzyme linked immunosorbant assay

Question 10

How to do the ELISA test?

Answer 10

Add sample containing antigens.
Add antibody, specific to the antigen.
Add 2nd antibody. Bind to the first and is bound to an enzyme.
Add a colourless substrate. Enzyme makes it coloured.
Colour produces shows the presence of antigens.

Question 11

Why would you use spearman rank?

Answer 11

To find out whether there is a significant correlation between 2 measurements of the same sample

Question 12

Why would you use the T-test?

Answer 12

To find whether there is a statistical difference between 2 means.
Sample size has to be less than 25.

Question 13

Why would you use chi-squared?

Answer 13

To compare measurements relating to frequency of individuals in categories.
Tests whether observed frequency fits the expected one.