Biological Molecules

Question 1

Define monomer

Answer 1

A small, basic molecular unit
E.g monosaccharides

Question 2

Define polymer

Answer 2

A large, complex molecule
E.g polysaccharides

Question 3

Define condensation reaction

Answer 3

The making of new chemical bonds by releasing a molecule of water.

Question 4

Define hydrolysis reaction

Answer 4

The breaking of bonds by adding a molecule of water.

Question 5

What is the general formula for a monosaccharide?

Answer 5

CnH2n0n

Question 6

What are the monosaccharides and what are their attributes?

Answer 6

Glucose,galactose,fructose.
They are soluble and sweet tasting

Question 7

How are alpha and beta glucose different?

Answer 7

On carbon 1 the Hydrogen is at the top and the OH is at the bottom for alpha. It is flipped for beta.

Question 8

Describe the method to test for reducing sugars and state the results

Answer 8

1. Add 2cm3 of the sample into a test tube
2. Add the same amount of benedicts reagent
3. Put it in a boiling water bath for 5 minutes.
   Pos result- low = green med= orange high= brick red

Question 9

Describe the method to test for non reducing sugars and state the results.

Answer 9

1. Add benedicts reagent to 2cm3 of the sample and heat in a water bath.
2. Sample stays blue so you add HCl and boil for 5 mins
3. Then add NaHCO3 to neutralise the sample
4. Add benedicts reagent and heat
   Pos result - low= green med = orange high= brick red