Carbohydrates Flashcards
What is the general formula for carbohydrates?
(CH2O)n
How do monosaccharides combine to form disaccharides?
Through a condensation reaction, making water as a byproduct.
What is the name of the bond between carbons in disaccharides?
Glycosidic bonds
What is polymerisation?
The process of bonding many monomers by condensation reactions to form one large molecule.
What are the three polysaccharides that you need to know?
Starch, cellulose and glucose
How is starch made?
By many alpha glucose molecules being joined by glycosidic bonds.
What are the two types of starch?
Amylose and amylopectin
What are the differences between amylose and amylopectin?
Amylose is formed by alpha glucose molecules joined together only by 1-4 glycosidic bonds, while amylopectin also contains 1-6 glycosidic bonds (one 1-6 bond every 25 glucose subunits).
What is the structure of amylose, and what are its properties?
It is formed in a helix shape, making it more compact and much less soluble than the glucose used to make it.
What is the structure of amylopectin, and what are its properties?
It has a branched structure due to its 1-6 glycosidic bonds. It is insoluble, compact, and branched.
What is glycogen?
It is functionally equivalent to starch in animals and fungi.
Why is glycogen good for being in animals?
It forms more branches than amylopectin, meaning it’s more compact and less space is needed for it to be stored, which makes it good for animals as they are mobile. Its branches also means there are many free ends where glucose molecules can be added or removed, speeding up the processes of storing or releasing glucose molecules.
What is the structure of cellulose?
It is made of two beta glucose molecules. As beta glucose molecules can’t bond together like alpha glucose molecules, one of the molecules has to be turned upside down. This makes it unable to coil or form branches, making a straight chain molecule.
What are the bonds between cellulose molecules forming microfibrils called?
Hydrogen bonds
What is a main feature of monosaccharides?
They are soluble in water due to their large number of hydroxyl (OH) groups which can form hydrogen bonds with water molecules.
