Unit 1- Carbohydrates Flashcards
What elements make up carbs?
C,H,O
Give 3 examples of hexose sugars
Glucose
Galactose
Fructose
Give 3 examples of pentose sugars
Ribose, deoxyribose, ribulose (photosynthesis)
Describe the structure of Alpha glucose
Carbon hexose ring with an oxygen in the top right corner
Methyl group with an OH on the top left carbon
Both the OH groups on side carbons face down
Describe the structure of Ribose
Carbon pentose ring with oxygen as the top point
Methyl group on carbon adjacent the oxygen
Methyl group also has a OH group
Every other carbon has OH group apart from carbon with methyl group
What joins 2 monosaccharides
Glycosidic bond (COC)
What type of reaction is polymerisation
Condensation
What type of reaction is the breakdown of polysaccharides
Hydrolysis
Everything we know about maltose:
- disaccharide of 2 glucose molecules
- formed from digestion of starch by amylase
Everything we know about sucrose
- glucose fructose disaccharide
- less reactive than glucose so plants use it to transport sugar
Everything we know about lactose
- galactose and glucose disaccharide
- found in mammalian milk
Definition of a polysaccharide
Chains of glucose monomers joined together by glycosidic bonds
Benefit of using starch as a storage
- compact
- insoluble so doesn’t change water potential of the cell resulting in osmosis and lysis of cells
Structure of amylose
It is a poly (1-4) glucose, Long glucose chain that coils into an alpha helix
- more compact with less branches
Structure of amylopectin and a benefit of this
Made of 1-4 glucose with some 1-6 branches
- more ends means it can be hydrolysed at more places by amylase enzymes releasing more energy per second
Where is glycogen found?
Muscle and liver cells
Everything we know about glycogen:
- animal storage of sugars
- lots of branches
- broken down to glucose by glycogen phosphorylase
- many ends means it releases lots of energy per second
Structure of cellulose?
Poly (1-4) glucose, of Beta glucose which forms rigid glycosidic bonds
- cellulose chains are straight and linked together with hydrogen bonds to form microfibrils which give the strength to cell walls
