Biomolecules 2 Flashcards
Monosaccharide Def.
A single carbohydrate (saccharide) molecule consisting of O, H, C. Building blocks of carbohydrates
Monosaccharide Structure
Ketones/ poly-hydroxy aldehydes. Emperical Formula = (CH2O)n ( where n = 3 - 7). Form ring structures (cyclisation)
Aldehyde group
-O (double bonded to carbon) H (single bonded to C)
Ketone Group
O (double bonded to middle carbon)
2 Examples of Triose
Glyceraldehyde (aldose) and Dihydroxyacetone (ketose)
5 Pentoses Examples
Ribose, Deoxyribose, Ribulose, Xylulose, Xylose (glycoprotein)
Hexoses Examples
Glucose, Fructose, Galactose and Mannose
How rings are formed in aldehydes
in
Glycosidic Bond def.
Bond between 2 sugars (glyco = carbohydrate)
Oligosaccharide
12/13 combined monosaccharides. Associated with proteins + lipids (eg cell membrane)
Hydroxy
-OH group
Isomer (def.)
Substances that have the same chemical formulas but different structures (gives different tastes)
What carbon is included in cycle in ketose
2nd carbon (carbon beside carbon bonded to O)
Anomeric Carbon
Carbon 1 (defining group attached, OH ) in cyclised aldose
2 Types of Anomeric Carbons
Alpha and Beta
Alpha Anomeric Carbon Classification
OH (hydroxyl) group close to ground
Beta Anomeric Carbon Classification
OH (hydroxyl) group close to sky
Factors Effecting Type of Glycosidic Bond
No. of carbons in chain + position of anomeric hydroxyl group (up/ down)
Structures carbohydrates can bind to
Carbohydrates, nitrogen bases, aromatic rings, proteins, lipids
Notation of Glycosidic Bonds
(alpha/beta) no. of carbon attached on left molecule (to) no. of carbon attached on right molecule
Ketose Def.
Sugar with ketone group (O double bond)
Aldose Def.
Sugar with aldehyde group (OH)
Polyscaccaride
Carbon chain where n >12
Polysaccharide Variations
Monosaccharides, Glycosidic Bonds, Branch Points (glycosisdic bonds attach to adifferent no. carbon), Structure
Functional Polysccharides
Glycogen (sugar store - animals, glucose homo-polymer), Starch (sugar store -plants), Cellulose (plant structure, homo-polymer glucose)
Glycogen Bond + Branched Structure
Bond: alpha 1-4. Branches every 12-14 residues (alpha 1-6)
Starch Composition
80-85% Amylopectin, 15-20% Amylose
Amylopectin Structure
Bond: Alpha 1-4. Branched every 24-30 residues Alpha 1-6
Amylose Structure
Bond: Alpha 1-4. Non-branched, helical structure
Celulose structure
Bond: Beta 1-4. Long straight chains
Lipid Functions in Body
Energy source (beta oxidation/ Ketogenesis in liver), cells + organelles structural component, cellular signaling eg Steroids
Lipid Building Block
Fatty Acids - hydrophobic carbon chain with Carboxyl (double bond O and single bond OH terminal). 2 Types
Differences between saturated and unsaturated fatty acids
Saturated single bonds, unsaturated 1+ double bond(s), Saturated is flexible, Unsaturated carbon position defined by distance from carboxyl end
Omega End Def.
The opposite end of the chain from the carboxyl group. Eg omega 3 is 3 carbons away from opposite chain end to carboxyl group
Lipid Classifiers
Fatty Acids (saturated/unsaturated/omega), Presence of glycerol (neutral charge mono to tri-acylglycerol or charged phospholipids)/ Absence of glycerol (eg steroids, sphingolipids), lipoproteins/lipopolysaccharides
Fatty Acid Cahin length Notation
No. carbons in chain : no. of double bonds (positions of double bond relative to carboxyl)
TRiglycerides Structure and Function
3 Fatty acids + glycerol. Principal storage form of energy. Stored in adipose
Diaccylglycerol Structure + Functions
gycerol + 2 fatty acids. Intracellular signaler, calcium mobilisation
Monoacylglycerol Structure + Formation
glycerol + 1 fatty acid. Product of triglyceride breakdown in fat digestion
Phospholipid Structure + Function
Hydrophillic, negative cahrgephosphate head. Hydrophobic fatty acid tails. Component of cell membrane
Sphingolipid Structure
sphingosine (sugar) + fatty acid + substituent (eg H)
Steroid Structure
Fused ring with hydroxyl/keto group on C 3
Steroid Functions
Metabolic precursor: vitamin D, bile-acid, hormones. Key role in membrane structure
Lipoprotein Structure
Phospholipid layer with cholesterol + protein. Hydrophobic core of triglycerols and cholesteryl esters
Essential Fatty Acid
Linoleic Acid (omega 6 FA) + Alpha linoleic fatty acids (omega 3)
