Carbs

• Carbohydrates have important structural and metabolic roles.
• Chemically, carbohydrates are aldehyde or ketone derivatives of polyhydric alcohols.
• Glucose is the most important carbohydrate.
• Intracellular traffic and recognition facilitated by cell surface carbohydrate molecules.
• Diabetes Mellitus – Oral Glucose Tolerance Test (OGTT)
• The oral glucose tolerance test (OGTT) measures the changes in blood glucose after a fixed amount of glucose (normally 75g) has been administered and normally after 2h post consumption.
• Structural and mechanical components of cell walls, insect exoskeletons, cartilage and synovial fluid and nucleic acids.
• Carbohydrates can be broken down to produce ATP or stored as starch – chloroplasts in leaves or as glycogen in the liver/muscles.
• Carbohydrates serve important structural needs: cellulose in plant cell walls, peptidoglycan in the cell wall of bacteria, and sugar-phosphate backbone in DNA/ RNA.
• Oligosaccharides are attached to the outer surface of the plasma membrane via special proteins or special lipids.
• The general formula for monosaccharides is (CH2O)n.
• Monosaccharides are important fuel molecules in addition to being building materials for nucleic acids.
• Monosaccharides cannot be hydrolysed into simpler carbohydrates.
• Monosaccharides may be classified by number of carbon atoms and aldehyde or ketone group.
• Aldehydes have one carbon and one hydrogen attached to the carbonyl group, while ketones have both groups attached to the carbonyl group are carbon.
• Glyceraldehyde, Pyruvic acid, Glycerol, Monosaccharide, Triose, and Aldose are examples of monosaccharides.
• Cellulose is an isomer of α-amylose with β-glycosidic linkages between two glucose residues.
• The end glucose molecules can easily be removed to provide energy.
• Glycogen is important as stored energy in animals, within glycogen granules.
• Animals convert excess consumed glucose into glycogen, mostly in the liver and muscles.
• Cellulose is essential for gut health and absorption as it provides fibre to help move food through our digestive system.
• Animals store glycogen then hydrolyse it when they need a supply of energy.
• Glycogen is important for animals which eat other animals as part of their diet, providing energy for other animals.
• Dihydroxyacetone, Glyceraldehyde, and Triose are examples of ketoses.
• Cellulose is a straight chained and unbranched polymer and is one of the most abundant organic compounds in the biosphere.
• Hyaluronic acid is an important component of ground substance, synovial fluid (fluid that lubricates the joints) and the vitreous humor of the eye.
• Glycogen is a large branched polymer of glucose residues with α-1,4 glycosidic bonds and branches roughly every 10 units in an α-1,6 glycosidic bond.
• Glycogen has a very large branched structure (i.e. very compact) which does not dissolve easily and is too big to leak out of the animal cell.
• Hyaluronic acid consists of 250-25000 β(1→4) linked disaccharide units, consisting of D-glucuronic acid and N-acetyl-D-glucosamine linked by a β(1→3) bond.
• 10^6 glucose molecules are the largest molecules in nature.
• Ribose, Fructose, and Glucose are examples of hexose sugars.
• Fischer projections are a convenient way to represent mirror images in two-dimensional form.
• Glucose Anomers Harworth projections do not explicitly show the presence of carbon atoms in the ring. This allows easy depiction of the stereochemistry of the sugar.
• An additional asymmetric centre is created when a cyclic hemiacetal is formed.
• Examples Glucose Galactose Fructose
• Polysaccharides: Learning Objectives
• Most of the monosaccharides in mammals are D sugars, and the enzymes responsible for their metabolism are specific for this configuration.
• The C-1 carbon atom is called the anomeric carbon atom, and the α and β forms are called anomers.
• Examples of Furanose rings
• Describe bonding between monomers which form: