Section 1:Biological Molecules Flashcards
What is a monomer?
An individual molecule that makes up chains of individual molecules
What is a polymer?
When monomers join together to form long chains
Give three examples of monomers
- Monosaccharides
- Amino Acids
- Nucleotides
Give two examples of polymers
- Carbohydrates
- Proteins
Describe what a condensation reaction is
A reaction which produces a molecule of water when a new sub-unit is attached
Describe what a hydrolysis reaction is
The process of breaking the bonds that link the sub-units of a polymer using water
What are the monomers in carbohydrates?
Saccharides (sugars)
List four monosaccharides
- α-glucose
- β-glucose
- Fructose
- Galactose
What are maltose, sucrose and lactose formed from?
Maltose=α-glucose+α-glucose
Sucrose=α-glucose+fructose
Lactose=α-glucose+galactose
What type of reaction occurs between two monosaccharides and what bond forms?
A condensation reaction takes place
Glycosidic bond is formed
Are monosaccharides reducing sugars or
non-reducing sugars?
All reducing sugars are monosaccharides
Describe the test for reducing sugars
Add benedict’s reagent(equal volume to test sample) and place in a boiling hot water bath(80-90)
Orange colouration reducing sugar present
Describe the test for
non-reducing sugars
- Add benedict’s reagent and place in a hot water bath
- If the colour does not change add dilue HCl acid and place in hot water bath
- Add NaCO3, then benedict’s reagent
Describe how polysaccharides are formed
Many monosaccharides are joined/combined in a condensation reaction
Describe the test for starch
Add two drops of iodine solution, to the test sample
If starch is present the solution will turn blue-black
Give the name of three polysaccharides
- Starch
- Glycogen
- Cellulose
What is the main role of starch?
Energy storage
What monomer units is starch made up of?
α-glucose
Five points
Why is starch’s structure suitable for energy storage?
- Insoluble~don’t affect WP~water not drawn in by osmosis
- large and insoluble~doesn’t diffuse out of cells
- compact~stored in a small space
- when hydrolysed forms α-glucose ~easily transported and readily used in respiration
- branched form has many ends~each can be acted on simultaneously~glucose monomers released very rapidly
What is the structure of starch?
α-helix held together by hydrogen bonds
What two different polysaccharides is starch made up of?
Amylose and amylopectin
What is the main function of glycogen?
Storage in animals