Carbohydrates Flashcards
What is a monosaccharide?
A single sugar, a basic carbohydrate monomer
What are disaccharides?
Dissacharides are double sugars formed from 2 monosaccharides
What are polysaccharides
Complex molecules consisting of many monomers
What is the formula for all glucose molecules
C6H12O6
Draw an α-glucose molecule
Draw a β-glucose molecule
What is an isomer?
An Isomer is two substancess that have the same molecular formula but different structural formula
Disaccharides are formed when to monosaccharides undergo a ______ reaction
Condensation reaction
The disaccharide can be broken down into two monosaccharides in a _______ reaction
hydrolysis
When two monosaccharides join they form a_________
1,4 glycosidic bond
Two important disaccharides are:
Maltose= 2 alpha glucose
Sucrose= Fructose and alpha glucose
What is the formula for disaccharides
C12H22O11
What is the general formula of polysaccharides?
(C6H10O5)n
The 3 polysaccharides you need to know:
Starch, glycogen and cellulose
Starch
mixture of amylose and amylopectin.
Amylose is is many alpha glucose molecules linked by 1-4 glycosidic bonds. Unbranched
Amylopectin is many alpha glucose molecules linked by 1-4 glycosidic bonds. It is branched every ten glucose monomers and has 1-6 glycosidic bonds.
Why is starch such a good storage molecule
Starch is an excellent storage molecule because:
both amylopectin and amylose are compact containing more glucoes in a small space
Insoluble in water
Being a large molecule it will not easily pass through cell membrane
The branching nature means many terminal ends which means hydrolysis can occur quicker
Glycogen
Glycogen is found in animal cells and is in the form of long aplha glucose chains. They branch every 8 units.
Why is glycogen a good storage molecule
compact
soluble
more terminal ends=faster hydrolysis
Cellulose
Structural role, made off monomers of beta glucose;
two chains are adjacent and are anti-parallel
they form hydrogen bond cross linkages
they group together and form microfibrils
plant cell walls= microfibrils in lattice structure in improve lattice strength
What are lipids
Lipids are insoluble in water byt are soluble in organic solvents
The main types of lipids are triglycerides, phosopholids
triglycerides
Triglycerides are made of glycerol and a fatty acid
In each triglyceride one glycerol molecule is joined with 3 fatty acid molecules in a condensation reaction
AN ESTER BOND IS FORMED IN EACH CONDENSATION REACTION
Excellent energy store as they release more energy per unit mass than carb. Important for insulation and protection
Saturated and unsaturated fats
Saturated fats= LInked by C-C single bonds
Unsaturated fats= linked by C=C double bonds (if there is one bond it is monounsaturated if there are more it is polyunsaturated)
Fats and Oils?
fats=solid at RC, animal product and usually formed of saturated chains
Oils=liquid at RC, plant products and are usually formed of unsaturated chains
Phospholipids
Hydrophobic tails and hydrophilic head. They are polar molecules, important for determining their orientation
