Polymers, amino acids, proteins and DNA Flashcards
What is an addition polymer?
A long chain formed from many monomers and no other product is formed
What are the two main types of condensation polymers?
Polyesters
Polyamides
What are polyesters?
Formed from carboxylic acids and alcohols
Have ester links
What are polyamides?
Formed from carboxylic acids and amines
Example of condensation polymers (3)
Terylene
Nylon
Kevlar
What type of condensation polymer is terylene?
Polyester
What is terylene made up of?
ethane-1,2-diol
benzene-1,4-dicarboxylic acid
What are the uses of terylene? (2)
Used to make carpets, clothing
Heat treated polyesters used for drinks bottles
What functional group is formed when an amine and carboxylic acid react?
Amide
What type of condensation polymer is nylon?
Polyamide
What type of condensation polymer is kevlar?
Polyamide
Monomers of nylon 6,6
1,6-diaminohexane
hexane-1,6-dicarboxylic acid
Monomers of kevlar
benzene-1,4-diamine
benzene-1,4-dicarboxylic acid
Properties of nylon (2)
Elastic, strong abrasion resistant
Uses of nylon (1)
Used as fibres in clothing
Properties of Kevlar (3)
Strong, light and heat resistant
Uses of Kevlar (2)
Used in the manufacture of body armour and crash helmets
Why are addition polymers non-biodegradable? (2)
Non polar C-C bonds so they cannot by hydrolysed
Therefore, they cannot be broken down by nucleophiles
Why are condensation polymers biodegradable? (2)
Can be hydrolysed
The delta positive C of the polar C=O can be attacked by nucleophiles
Why do amino acids have high melting points?
Due to the strong electrostatic attractions between zwitterion
Under what conditions can condensation polymers be hydrolysed?
Acidic or basic conditions
What happens to amino acids in acidic conditions?
Get protonated
What happens to amino acids in alkaline conditions?
Get deprotonated
When linking amino acids, how must they be written?
NH2 group on the left and COOH on the right
Hydrolysis of peptides require what conditions
Boil for 24 hours
6 moldm-3 HCl catalyst
Why do hydrogen bonds form in secondary structures of amino acids?
Electron deficient H
Attracts the lone pair on the O
Two cysteine amino acids form what kind of bonds?
Disulphide bonds
To form a disulphide bond, what position must the two cysteine molecules be in?
Parallel to each other
What kind of proteins are enzymes?
Globular
One property of enzymes
Stereospecific
How does drug development take place using enzyme inhibition?
An undesirable biological process occurs which is catalysed by an enzyme
A computer is used to determine the shape of the active site and design another molecule which will fit into the active site. This must be the correct enantiomer
This new molecule is called the inhibitor
What is the sugar called in DNA?
2-deoxyribose
How does cisplatin work? (2)
Binds to the DNA in cancerous cells and a bond forms between platinum and nitrogen atom on guanine (in a ligand replacement reaction)
Prevents the DNA from unwinding and so the cancer cells cannot replicate
Things to consider when using cisplatin (4)
Cis-platin will also bind to the DNA in healthy cells.
This can cause unwanted side effects.
The cis-platin drug can be targeted straight to the cancer cells to reduce the effect on healthy tissue.
It can also be used in minimal amounts
