Dr Bell Flashcards
What’s a polymer and what’s a monomer ?
Polymer - a long complex chain of similar monomers
Glucose +glucose =
Glucose +fructose =?
Glucose +galactose=
Maltose
Sucrose
Lactose
How to test for a reducing sugar
Benedict’s and heat , brick red precipitate is a positive result.
What is the main storage material in plants ?
Starch
Describe starch
Plants store excess glucose as starch , contains amylose (long unbranched , coiled , compact ), amylopectin(long batches alpha glucose , side branches that can be easily broken down )
Insoluble in water sod oesnt affect water potential.
What is the main storage material in animals ? Describe it
Glycogen , polysaccharide of alpha glucose many side branches , very compact.
How is cellulose suites for its purpose ?
Long , unbranched beta glucose, straight cellulose chains held by hydrogen bonds , microfribrils that give good support for cell walls.
What’s the test for starch ?
Add iodine in dissolved potassium iodide solution. Positive result - blue black coloration
What are lipid made form ?
Proteins carbs and hydrocarbons
Describe a triglyceride
One molecule of glycerol , three fatty acids(hydrophobic tails men’s they are insoluble ) , three ester bonds
What’s the basic structure of a fatty acid ?
O—C—R
OH
What’s the difference between saturated and unsaturated ?
Unsaturated fatty acids have double bonds between each carbon and can cause the hydrocarbon chain to kink.
How are triglycerides formed ?
Condensation reaction between glycerol and. A fatty acid to form ester bonds.
Describe a phospholipid
Found in cell membranes , two fatty acids , one phosphate head , two ester bonds.
What are the properties of triglycerides and phospholipids ?
Triglyceride-energy storage molecules , long HC chains have lots of chemical energy , insoluble in water don’t affect water potential due to fatty acid tails facing inwards.
Phospholipids- make up Bauer of cell meme range , hydrophilic heads , centre is hydrophobic so water soluble substances can’t pass through.
How to test for a lipid
Emulsion test, shake substance with ethanol and pour solution into water , any lipid will= milky emulsion
What are proteins made from?
Monomers =amino acids , dipepride =two amino acids , polypeptide =several amino acids , proteins are made from one or more polypeptides.