Testing For Biological Molecules: Reducing sugars.,

Question 1

What are the 2 types of sugars?

Answer 1

= reducing and non-reducing sugars.

Question 2

What is a reducing sugar?

Answer 2

= can donate an electron to another molecule.

Question 3

Are monosacharides reducing or non-reducing and what about dissacharides?

Answer 3

ALL Monosacharrides are reducing
e.g: Glucose, fructose and Galactose.

SOME dissacharides.
e.g: Maltose + Lactose. (surcorse is non-reducing(,

Question 4

What is a safety precaution for this practical?

Answer 4

= wearing goggles.

Question 5

How do we start this practical?

Answer 5

= grinding the food with distilled water
= filtering away the solid food particles.
= place 3cm^3 of food solution into a boiling tube. `

Question 6

What is the 2nd step for the practical?

Answer 6

= adding 3cm^3 of benedicts solution.
= place the boiling tube into a beaker of boiling water
= leave for 5 minutes.

Question 7

What does benedicts solution contains?

Answer 7

= Cu2+ ion (copper ion)- makes solution blue.

Question 8

If there is no reducing sugar present what happens?

Answer 8

= remains blue there is no reducing sugar present.

Question 9

If reducing sugar is present what happens?

Answer 9

= Adds an electron to the CU+ ion.
= forms a Cu+ ion and red precipitate (solid).

Question 10

If there is a small amount of reducing sugar present what happens?

Answer 10

= only a very small amount of reducing sugar forms a red precipitate.
= green.

Question 11

If more reducing sugar is present what does the color turn into?

Answer 11

= color turns yellow.
= higher turns orange., `

Question 12

What is the problem with using benedicts solution?

Answer 12

= gives us an approximate idea of the amount of reducing sugars.
= shows a narrow range of color changes
= all humans perceive colors differently.

Question 13

Why do scientists call thebenedicts test semi-qunatitatve?

Answer 13

=