3.1.1 - Monomers and Polymers Flashcards
(21 cards)
What two things join together to create a disaccharide?
Monosaccharides
Give 3 examples of monomers
Monosaccharides, amino acids and nucleotides
What type of reaction joins two molecules together?
Condensation reaction
Define a condensation reaction
A condensation reaction joins two molecules together with the formation of a chemical bond and involves the elimination of a molecule of water.
What is a hydrolysis reaction?
A hydrolysis reaction breaks a chemical bond between two molecules and involves the use of a water molecule
Biological molecules are made of 4 main elements. What are they?
Hydrogen, Carbon, Oxygen and Nitrogen
What is polymerisation?
Monomers that join together to form polymers.
Define a monomer
A molecule that can be joined to form polymers
Define a polymer
Many monomers joined together
What two monomers make up the disaccharide Maltose, and what is its formula?
2 alpha glucoses, and C12H22O11
What two monomers make up the disaccharide sucrose, and what is its formula?
alpha glucose and fructose, and C12H22O11
What two monomers make up the disaccharide lactose, and what is its formula?
alpha glucose and galactose, and C12H22O11
What is the formula for alpha glucose?
C6H12O6
What is the formula for beta glucose?
C6H12O11
What is the formula for galactose?
C6H12O11
What is the formula for fructose?
C6H12O11
What colour does the precipitate change from in a benedicts test?
Blue - green - yellow - orange - brick red
What test is used to test for sugars?
Benedicts test
Describe how you carry out a benedicts test (reducing sugar)
1) Add benedicts reagent to a sample and heat it in a water bath thats been heated to boiling point.
2) If the test’s positive it will form a coloured precipitate
3) The higher the concentration of reducing sugar, the further the colour change goes.
Describe how you would carry out a test for a non-reducing sugar?
If the test came back negative for a reducing sugar:
1) You would get a new sample, dilute it with hydrochloric acid and bring the sample to the boil in a water bath. You then neutralise the sample with sodium hydrogencarbonate and then carry out the benedict’s test as you would for a reducing sugar.
2) If the test is positive, it will form a coloured precipitate (same as reducing sugar, blue - green - yellow - orange - brick red)
If the tests negative, the solution stays blue meaning that no sugar is present in the sample (either reducing or non-reducing)
What test do you use to test for starch, and how do you conduct it?
The iodine test. Add iodine dissolved in potassium iodide solution to the test sample. If there is any starch present the solution changes from browny-orange to a dark, blue-black colour.
