Carbs and lipids W1 Flashcards
(25 cards)
Polymers of glucose
Cellulose - plants
Chitin - shellfish exoskeleton
Pectin - gelling agent
What is the 6 membered ring
A sugar
Polysaccharide examples
Starch and cellulose - multiple glucose molecules
Heterogenous
Not every sugar is exactly the same
Simplest carbs, monosacc, are classified as?
Classified as Aldoses or ketoses depending on wether the carbonyl group is a aldehyde or a ketone
Simple definition of a sugar
Poly alcohol with an aldehyde or a ketone
Carbon numbering of a sugar
Starts at the end of the carbon chain that the carbonyl is closest to
Numbering of the carbon chain in monosaccharides starts from the end
bearing the carbonyl group, C-1 for the aldoses and C-2 for the ketoses.
Different ways of drawing glucose
Fisher - no stereo config
Zig zag - more accurate with wedges and dashes
Mills - sugars aren’t a line but cyclical , flat mol (not accurate)
Haworth - which ones point above and below the ring (not accurate)
Chair - most accurate, shows stereo config and correct shape as well as where the hydroxyl groups are pointing
What do you get if you oxidise a primary alcohol
Aldehyde
Oxidised an aldehyde into a…
Carboxylic acid
Secondary alcohol oxidises to…
A ketone
Definition of a lipid
Defined by a “physical property”,rather than a common structural
feature.
Naturally occurring molecules (usually fatty acids or their derivatives) with very limited solubility in water
Can be isolated from organisms by extraction with a nonpolar organic solvent (eg hexane).q
Structural classes of lipids
Hydrolysable and non-hydrolysable
Hydrolysable lipids
Carbon backbone with O on it with ester linkages and alcohol side chains
Non-Hydrolysable lipids
Ie cholesterol
Can’t hydrolysis
Very greasy
Saturated fatty acid
No double bonds
Generally unbranched
Contain even no.carbon atoms between 10 and 24
Un-Saturated fatty acid
Contain double bonds
Config of the = are Z (cis)
With more than one = are called polyunsaturated
Types and functions of lipids : energy storage lipids
Triacylglycerols
- fats and oils
Types and functions of lipids : membrane lipids
Phospholipids
- glycerophospholipids
- spingophosholipids
Cholesterol
Spingoglycolipids
- cerebrosides
- gangliosides
Types and functions of lipids : emulsification lipids
Bile acids
- cholic acid
- deoxycholic acids
Types and functions of lipids : messenger lipids
Steroid hormoes
- sex hormoes
- adrenocorticoids
Eieosanoids
- prostaglandins
- thromboxanes
- leukotriens
Types and functions of lipids : protective coating lipids
Biological waxes
Triacylglycerols (TAG)
Triesters of one mol of glycerol with 3 fatty acid mols
Glycerophospholipids
(also called phosphoglycerides) are the main structural lipids in cell membranes and play key roles in membrane fluidity, signaling, and lipid metabolism.
They are built on a glycerol backbone, and typically consist of:
- Glycerol (3-carbon alcohol)
- Two fatty acid chains – attached to the first and second carbon via ester bonds
- Phosphate group – attached to the third carbon
- Polar head group – attached to the phosphate
