Biomolecules Flashcards
What are the four main classes of biomolecules?
Sugars; nuceleotides; fatty acids; amino acids.
Sugars (Ex, poly., funct.)
Example = glucose Polymer = glycogen Function = energy storage
Nuceotides (Ex, poly., funct.)
Example = ATP Polymer = DNA Function = carries genetic information
Fatty acids (Ex, poly., funct.)
Example = stearic acid Polymer = triacylglycerols Function = long term energy storage
Amino acids (Ex, poly., funct.)
Example = alanine Polymer = proteins Function = enzymes etc.
Give an example of a cell with a glycosylated cell surface protein
RBC’s in ABO blood groups
Aldose
A sugar with a carbonyl group at the end of the carbon chain.
Ketose
A sugar with a carbonyl group in an intermediate carbon in the chain.
What forms can sugars come in, structurally?
Linear or ring
How do ring-shaped sugars form from linear sugar
Nucleophilic attack by the lone pair of electrons on the oxygen in the -OH on the penultimate carbon atom in the chain on the carbon atom in the carbonyl group. This carbon atom then is the anomeric carbon atom.
What are the a and B forms of a sugar?
a-sugars have the -OH group on the anomeric carbon facing down; B-sugars have the -OH group on the anomeric carbon facing up.
Monosaccharide examples
Glucose, fructose, galactose
Disaccharide examples
Maltose = glucose + glucose Sucrose = glucose + fructose Lactose = glucose + galactose
Polysaccharide examples
Glycogen = branched glucose polymer consisting of a(1,6) and a(1,4) glycosidic bonds. Amylose = linear glucose polymer made up of a(1,4) glycosidic bonds.
How is glycogen digested in the diet?
Salivary amylase causes hydrolysis at random a(1,4) glycosidic bonds.
Pancreatic amylase then produces a mixture of glucose monosaccharides and maltose disaccharides. Then maltase hydrolyses the a(1,4) glycosidic bonds to produce glucose which is then digested.
