Carbohydrates 1 Flashcards
What are monosaccharides and name 3 examples
They are single monomer of sugar. There are three important hexoses which are glucose, fructose and galactose.
What is an anomeric carbon?
Different anomers are mirror images of each other. On glucose the anomeric carbon is carbon one and it stabilises the structure and it can be oxidised.
What is a disaccharide and name some examples
These are sugars that are formed from sugar monomers held together by glycosidic bonds. The bond forms between the anomeric carbon of one monosaccharide and the hydroxyl group of another. Three disaccharides are maltose, sucrose and lactose.
What is a reducing sugar?
A reducing sugar is one that itself is oxidised so can reduce another substance (as it has oxidisable anomeric carbon)
Some examples are maltose and lactose.
What is a non reducing sugar?
It is one that doesn’t have a free anomeric carbon so it can’t be oxidised and therefore can’t reduce other substances. An example is sucrose.
What is a polysaccharide?
These are polymers of sugars. They differ in the length of their chains, amount of branching, type of monomers and the type of bonds they have.
Homopolysaccharides have a single monomeric species.
Heteropolysaccharides have two or more monomer species.
What types of glucose does starch contain and how much?
25% of amylose.
75% of amylopectine
What is the structure of starch?
It has few reducing ends and many non reducing ends. Amylose and amylopectin form alpha helix structures.
What is glycogen?
It is used by animals to store glucose. It is a polymer of glucose and is more branched than starch. It is mostly found in the liver and skeletal muscle.
Why is glucose stored as polymers?
For compactness.
Speeds up formation and degradation of glycogen and amylopectin due to their non reducing ends.
What is a difference between glycoproteins and proteoglycans?
Glycoproteins have more protein than carbohydrates and vice versa for proteoglycans.
What are glycosaminoglycans and where are they found?
They are unbranched polymers made from repeating units of hexuronic acid and an amino sugar. They are found in mucus and synovial fluid round the joints.
