2.1.2 Biological Molecules Flashcards
What is the general formula for carbohydrates?
Cx(H2O)y
What is a monosaccharide?
Single unit of sugar/ carb
What is a disaccharide?
Two units of sugar/ carb
What is a polysaccharide?
2+ units of sugar/ carb
What is the molecular formula for glucose?
C6 H12 06
What is a hexose monosaccharide?
A single carb unit made of 6 carbons
How are carbons numbered in a hexose/ pentose ring?
Clockwise from the Oxygen atom
What’s the difference between an Alpha and Beta glucose?
Position of 0H- group on C1; alpha down; beta up
What are 2 properties of glucose?
- Polar
2. Soluble in water (OH-)
Why does glucose need to be soluble?
Dissolve in cytosol of a cell
How is a gylcosidic bond formed?
Condensation reaction between two OH- groups of two glucose molecules, producing H2O
How are glycosidic bonds broken?
Hydrolysis reaction between two glucose molecules, using H2O and enzymes
Why are glycosidic bonds broken?
To release glucose from energy store
What is a pentose monosaccharide?
A single unit of sugar/ carb made of 5 carbons
What are two examples of pentose monosaccharides?
- Ribose (RNA)
2. Deoxyribose (DNA)
What two polysaccharides is Starch made up of?
- Amylose
2. Amylopectin
What bonds are in Amylose?
1-4 Glycosidic bonds between alpha
What bonds are in Amylopectin?
1-6 Glycosidic bonds 1:25 subunits and 1-4
Properties of Amylose? (3)
- Helix
- Compact
- Less soluble than glucose
Properties of Amylopectin? (2)
- Branched
2. More soluble than Amylose
Why is it useful that energy storage molecules (e.g starch) are branched? (2)
- Compact- store more at once
2. Stable- doesn’t react so easily, retain more glucose
What bonds are in Cellulose?
1-4 glycosidic bonds between beta glucose, every other beta upside down
What is the structure of Cellulose?
Straight chain
Why is Cellulose used for cell walls? (2)
- Forms microfibrils (H bonding) -> macrofibrils -> fibres
2. Fibres are strong and insoluble
What shape do 1-4 glycosidic bonds make?
Straight
What shape do 1-6 glycosidic bonds make?
Branched
Lipids are ____molecules made up of ____
Macromolecules; monomers
What does a triglyceride contain?
One glycerol molecule and 3 fatty acids
How are triglycerides formed?
Esterification; OH- from both molecules react and produce 3 molecules of water
What bonds are in triglycerides?
Ester
What kind of a reaction is esterification?
Condensation
How are triglycerides broken down?
Hydrolysis; water is added and enzyme Lipase (bc Trigl. are lipids)
What is a saturated fatty acid chain?
No double bonds
What is an unsaturated fatty acid chain?
C=C present
What is a monosaturated fatty acid chain?
One C=C present
What is a polysaturated fatty acid chain?
More than one C=C present
How do C=C affect triglycerides?
Make a kink in the chain, less compact, lower melting point
What is a phospholipid?
A triglyceride containing a phosphorus group instead of a 3rd fatty acid chain
Is the glycerol molecule still present in a phospholipid?
Yes
Which parts of a phospholipid are polar/ hydrophilic?
Phosphate group