[1.2] monosaccharides Flashcards
what is the general formula for a carbohydrate?
CₙH₂ₙOₙ
what do you call a sugar with 3, 4, 5 or 6 carbons?
c = 3 = triose
c = 4 = tetrose
c = 5 = pentose
c = 6 = hexose (eg. glucose)
what does it mean that alpha and beta glucose are optical isomers of each other?
- they have the same chemical formula, but are mirror images of each other
- the only difference between them is that the position of the H and the OH are switched
diagram of structure of alpha glucose
google it xoxo
diagram of structure of beta glucose
google it xoxo
what is a monosaccharide?
- the simplest form of carbohydrate
- there is one sugar present
how are disaccharides formed?
- two monosaccharides bond in a condensation reaction
- water is released
- glycosidic bond forms
where does a 1, 4 glycosidic bond form?
between carbon 1 on the first glucose and carbon 4 on the second
how are disaccharides broken down?
- hydrolysis reaction
- needs a molecule of water
- glycosidic bond is broken between 2 monosaccharides
examples of disaccharides + their enzymes
- glucose + glucose -> maltose (maltase)
- glucose + fructose -> sucrose (sucrase)
- glucose + galactose -> lactose (lactase)
uses of monosaccharides in living organisms: energy
large number of C-H in monosaccharides can be used to produce ATP during respiration (energy carrier molecules in cells)
uses of monosaccharides in living organisms: building blocks
polymerised to form polysaccharides eg:
- starch - energy storage in plants
- glycogen - energy storage in animals
- cellulose - main component of plant cell walls
- pentoses - used to form polymers eg. DNA/RNA and ATP
why do large molecules often contain carbon?
because carbon atoms readily link to one another to form a chain
what happens during a condensation reaction?
- a hydrogen atom from one monomer and a hydroxyl group from another can combine to form water
- this leaves a new covalent bond between monomers
