Carbohydrates - monosaccharides Flashcards
(27 cards)
what do all carbohydrates contain
hydrogen, oxygen and carbon with the general formula CxH2Ox
some carbohydrates are part of other molecules such as nucleic acids and glycolipids
how much of the mass of the human body do carbohydrates account for
10%
what are the functions of carbohydrates
- energy source (glucose)
- energy store (starch)
- structure (cellulose)
- functional groups (ribose in RNA and deoxyribose in DNA)
how many groups of carbohydrates are there and what are they
3 groups -
monosaccharides, disaccharides and polysaccharides
what is the common ending of monosaccharide and disaccharide
-ose
what is a monosaccharide
it is the simplest carbohydrate. important in living things as a source of energy. it is well suited because of its large number of C-H bonds. they are sugars which taste sweet
what are monosaccharides soluble/insoluble in
soluble in water and insoluble in nonpolar solvents
how are monosaccharides structured
straight chains or in ring or cyclic forms. they have a backbone of single bonded carbon atoms with one double bonded to oxygen atom to form a carbonyl group
how many carbon atoms does hexose, pentose and triose have
hexose - 6
pentose - 5
triose - 3
what kind of sugar is glucose
hexose sugar
what are hexose sugars monomers of
more complex carbohydrates
what do monosaccharide hexose sugars bond to form
disaccharides and polysaccharides
how are tetrose and triose structured
they exist as straight chains
how are pentose and hexose structured
in ring or cyclic form
which is the most abundant and important monosaccharide
glucose
what is the general formula for glucose
C6H12O6
describe properties of glucose
a major energy source for most cells, highly soluble, main form in which carbohydrates are transported around the body of animals
what is a structural isomer
molecules that have the same molecular formula but have a different structural arrangement of atoms
what are the isomers of glucose
alpha-glucose and beta-glucose
what is the difference between both isomers of glucose
the position of the -OH group attached to carbon 1. the alpha is below carbon 1 and the beta is above carbon 1
why are the isomers of glucose important
it has a major difference but a major effect in terms of biological roles. it is important when glucose molecules polymerise into starch
give other hexose monosaccharides
fructose and galactose
what is fructose
soluble, main sugar in fruits and nectar. it is sweeter than glucose
what is galactose
not as soluble as glucose and has an important role in glycolipids and glycoproteins
