2.1.13 Practical biochemistry

Question 0

What is the test for reducing sugars?

Answer 0

Add Benedict’s solution and heat to 80’ (in a water bath)

Question 1

What is the test for starch?

Answer 1

Add a few drops of iodine

Question 2

What is the test for non-reducing sugars?

Answer 2

Boil with hydrochloric acid, cool and neutralise with sodium hydrogencarbonate solution and repeat Benedict’s test.

Question 3

What is the test for protein?

Answer 3

Add biuret reagent

Question 4

What is the test for lipids?

Answer 4

add ethanol to extract lipid and pour alcohol into water in another test tube

Question 5

What is the colour change if starch is present?

Answer 5

Brown to blue/black

Question 6

What is the colour change if a reducing sugar is present?

Answer 6

blue to brick red

Question 7

What is the colour change if a non reducing sugar is present?

Answer 7

Blue to brick red on the second test

Question 8

What is the colour change if a protein is present?

Answer 8

blue to lilac

Question 9

What is the result if a lipid is present?

Answer 9

White emulsion forms near top of the water