Carbohydrates Flashcards
What is a polymer
Long molecule consorting of monomers
List polymers
Carbohydrates
Proteins
Nucleic acids
How are monomers made from polymers
Polymers ate dissembled to monomers by hydrolysis
How are polymers made from monomers
Dehydration reaction
2 monomers bind tighter through the loss of a water molecule
Monosaccharides
the simplest carbohydrates, small, monomeric molecules
Oligosaccharide
only a few monomer units are involved
Polysaccharide
long polymers of monosaccharides
What is maltose made of
Glucose ans glucose
Formula of monosaccharides
(CH2O)n
How are monosaccharides categorised
-location of the carbonyl group
-number of carbons in the skeleton
Trioses
Aldehyde such as glyceraldehyde
Ketone such as dihydorxyacetone
Aldose-ketone interconversion
Addition of water to form an endiol
Addition of another water molecule
Examples of pentoses
Aldose such as ribose
Ketose such as ribulose
Examples of hexoses
Aldoses such as glucose or galactose
Ketose such as fructose
Enantiomers of glyceraldehyde
-D-glyceraldehyde which has an oh on the right and L glyceraldehyde that has the oh on the left
-they are mirror images hence called enantiomers
-middle carbon is a chiral carbon
Enantiomers of glucose
D glucose (oh on the right)
L glucose(oh on the left)
Structure of alpha glucose
Draw it
Differences between alpha and beta glucose
In alpha the oh on carbon one is at the bottom
Examples of phosphate esters of monosaccharides
B-d-glucose-1-phosphate
D-glyceraldehyde-3- phosphate
B-d-glucose-6-phosphate
A-d-fructose-6-phosphate
Abbreviations of glucose
Glc
Abbreviation of glucosamine
GlcN
Abbreviation of N-acetylglucosamine
GlcNAc
Abbreviations of galactose
Gal
Abbreviation of Galactosamine
GalN
Abbreviation of N-acetylgalactosamine
GalNAc
Abbreviation of gluconic acid
GlcA
Abbreviation of N-acetylneuraminic acid (sialic acid)
NeuNAc
Role of trioses
The 3-phosphate is an intermediate in glycolysis
The 1-phosphate is an intermediate in glycolysis
Role of pentoses
Constituent of ribonucleic acid (RNA)
Constituent of deoxyribonucleic acid (DNA)
Role of hexoses
A major energy source for animal metabolism; structural role in cellulose
As part of lactose (milk); structural polysaccharides
A major plant sugar; part of sucrose; intermediate in glycolysis
How is maltose formed
Removal of water between two molecules of alpha glucose and the formation of glycosidic bond
How is sucrose formed
Removal of water between glucose and fructose forming a glycosidic bond
Examples of Polysaccharides
Starch
Glycogen
Starch
astoragepolysaccharideofplants,consists entirely of glucose monomers
Glycogen
a storage polysaccharide in animals
What monomer is found in cellulose
Beta glucose
Bonds in amylose
1-4 glycosidic bonds
Bonds in cellulose
1-4 glycosidic bonds
Structure of starch
-found in plastids
-amyloses is unbranched
-amylopectin is branched
Structure of glycogen
-extensively branched
Role of Amylase
-Amylase is an enzyme that breakdown starch (amylose and amylopectin) into disaccharides and trisaccharides.
-Amylases act on α-1,4-glycosidic bonds.
Structure of cellulose
-beta glucose monomers
-microfibrils which provide strength in lathe number
-many weak hydrogen bonds which provide strength and rigidity
What is chitin
-found in the exoskeleton of arthropods and is used in medicine for surgical thread as it decomposes
Hyaluronic acid
It is a structural component in cartilage and is present synovial fluid of joints and in the vitreous humour of the eye.
What can polysaccharides play a vital role in
Cell recognition as they act as cell markers
Function of carbohydrates
▪ Energy storage and generation (starch, glycogen)
▪ Biological structural materials (cellulose, chitin, etc)
▪ Polysaccharide on cell surface or attached to proteins aid in molecular recognition
Gram staining test
Gram-positive organisms have a thicker peptidoglycan cell wall compared with gram- negative bacteria. It is a 20 to 80 nm thick polymer while the peptidoglycan layer of the gram-negative cell wall is 2 to 3 nm thick and covered with an outer lipid bilayer membrane.
Function of polysaccharides
-strengthens plant cell walls
-stores glucose for energy
-strengthens exoskeletons and fungal cell walls
What is found in bovine cartilage
Proteoglycan
Role of heparin
Anti cougalant
