u2 areas to revise

Question 1

what is a protein and what are they used for

Answer 1

Proteins are the major structural materials of animal tissue and are also involved in the maintenance and regulation of life processes

Question 2

what are proteins made up of

Answer 2

many amino acids

Question 3

describe the formation of a protein

Answer 3

Proteins are made of many amino acid molecules linked together in condensation reactions. the amine group of one amino acid and the carboxyl group of another amino acid join and water is produced

Question 4

name and describe the link between two amino acids

Answer 4

amide (peptide) link - bond found in protein molecules where anime group and carboxy group join. H-N-C=O

Question 5

draw an isoprene unit

Answer 5

CH2=C(CH3)-CH=CH2 (2-methyl-1,3-butadiene)

Question 6

describe an ester link

Answer 6

COO

Question 7

describe the formation of an ester

Answer 7

condensation reaction between an alcohol and carboxylic acid. water is produced

Question 8

describe the breakdown of an ester

Answer 8

in hydrolysis, an ester reacts with water to break down into the parent alcohol and carboxylic acid

Question 9

describe emulsion

Answer 9

Emulsifiers for use in food can be made by reacting edible oils with glycerol. In the molecules formed, only one or two fatty acid groups are linked to each glycerol backbone. The hydrophobic fatty acid chains dissolve in oil whilst the hydrophilic hydroxyl groups dissolve in water, forming a stable emulsion.