polymers of life Flashcards
what is the general an amino acid?
central carbon surrounded by a hydrogen group, a carboxyl group, variable group and amine group
what are proteins an example of?
condensation polymers
how do you break down proteins?
by hydrolysis
reflux with moderately concentrated hydrochloric acid- hydrolysing the C-N bonds
what can you do to indentify amino acids in a protein?
hydrolyse the protein under reflux then use chromatography to separate
compare Rf values to known data base
what is primary structure of proteins?
the order of amino acid residues
what is the secondary structure of proteins?
the alpha coiling and formation of beta pleated sheets of the chain
held together by hydrogen bonds between peptide links- between -NH and -C=O
What is the tertiary structure of a protein?
the final folding determining the 3D shape f the protein
intemolecular bonds, ionic bonds and covalent bonds.
IDID between non polar R-groups
hydrogen bonds between polar R-groups
ionic bonds between ionisible R-groups
covalent bonds between sulfur containing R-groups on cysteine residues to form disulphide bridges
what is the structure of a nucleotide?
made of a phosphate, sugar and a base
what is the difference between DNA and RNA nucleotides?
DNA has deoxyribose sugar, RNA has ribose sugar
how is the sugar phosphate backbone formed?
phosphate units join by condensation with deoxyribose or ribose
how do bases join to the phosphate sugar backbone?
join by condensation with the deoxyribose
how many hydrogen bonds form between Adenine and Thymine?
2
how many hydrogen bonds form between Cytosine and Guanine?
3
describe DNA replication?
hydrogen bonds break between the DNA strands
bases of free nucleotides pair with complementary bases on nucleotides of DNA
- ensures correct nucleotides join in correct place
DNA polymerase joins sugar phsophate backbone of new chain
results in 2 identical molecules, the same as the starting molecules
describe DNA transcription
DNA helix unwinds to reveal a single stranded portion
the DNA bases attract free RNA nucleotides with complementary bases
the RNA nucleotides are joined together by RNA polymerase = mRNA
the DNA coils up again
mRNA is released to move arounds cell
describe DNA translation
ribosome attaches to mRNA at start codon
tRNA with correct anticodon bases pairs with start codon inside the ribosome
ribosome moves onto next triplet and different tRNA to bring next amino acid that the mRNA codes for
the two amino acids join by a peptide bond
the ribosome moves forward again and first tRNA breaks off from amino acid and next amino acid joins by the tRNA
continues until stop codon
what is a pharmocaphore?
the part of a drug that fits into the receptor site and makes it medicinally active
what are 4 things that determine how pharmocaphore interact with the receptor?
size - particular size to fit into receptor
shape - particular shape to fit into the receptor
bond formation - functional groups in pharmocaphores form temporary bonds with functional groups in the receptor
orientation- if pharmocaphore is E/Z optical isomer then only one will fit
describe the shape of rate versus substrate concentration curve for an enzyme catalysed reaction with reference to order.
at low concentrations of substrate, the order with respect to substrate concentration is one and rate increases as substrate increases however at higher concentrations of substrate the order with respect to substrate is zero as all active sites are in use for catalysis and substrate conc no longer has an effect on rate
what is made when a carboxylic acid reacts with metal?
redox reaction, forming carboxylate salt and hydrogen gas
what forms when carboxylic acid reacts with carbonates?
carboxylate salt, carbon dioxide, water
what is made when carboxylic acid reacts with alkali?
neutralisation, forming carboxylate salt and water
what is a zwitterion?
a compound with a positive and a negative charge on it
what is the structure of a zwitterion?
normal amino acid structure but with a coo- isntead of carboxyl group and NH3+ instead of NH2
what is a bronsted lowrey acid?
can donate H+
What is a bronsted lowrey base?
can accept H+
describe the reaction of an amine group with acid?
the lone pair on the nitrogen accepts proton forming daitive covalent bond with H+ and forming a cation
what is the formula of carboxylic acid?
COOH
what is the formula of a phenol?
benzene ring with a hydroxyl group
what is the functional group of an acyl chloride?
C=O
\
Cl
what is the fucntional group of an acid anhydride
| C = O | O | C = O |
What is the functional group of an ester?
| C = O | O |
What is the functional group of an aldehyde?
-C=O
\
H
What is the functional group of a ketone?
|
C = O
|
what is the functional group of a primary, seconday and tertary amine?
- NH2
- NH
- N
Nylon x,y
X= the number of carbon atoms in the diamine
Y= the number of carbon atoms in the dicarboxylic acid
what is the functional group of a primary amide?
-c=o
|
NH2
what are the conditions needed to make an ester and what reagents does it need?
concetrated sulfuric acid and under reflux (leibig condenser)
makes carboxylic acid and an alcohol
what conditions are needed for acidic hydrolysis of esters and what is made?
moderately concentrated HCl
forms a carboxylic acid and an alcohol
what conditions are needed for alkaline hydrolysis of aester and what is made?
NaOH
forms a sodium carboxylate salt and an alcohol
what is the functional group of a secondary amide?
C | NH | C = O
what conditions are needed for acidic hydrolysis of amide and what is made?
moderately concentrated HCl (4M)
Reflux, aqeous
carboxylic acid and ammonium
what conditions are needed for alkaline hydrolysis of amide and what is made?
moderately concentrated NaOH (2M)
reflux, aqeous
carboxylate ion and ammonia
what is formed when acyl chloride reacts with an primary amine?
secondary amide and HCl
what is formed when an acyl chloride reacts with alcohol?
carboxylic acid and HCl
what is the difference between addition and condensation polymerisation?
addition polymers involve double C=C bond opening and joining together to make long chains whereas condensation polymers have to have 2 functional groups these react with another functional group on another monomer to form a link and a small molecule such as water
what is a chiral carbon?
a carbon with 4 different groups on it
what are enantimers?
non superimposible mirror images - optical isomers
what do enantiomers do to light?
they rotate plane polarised light in opposite directions
what does nmr stand for?
nuclear magnetic resonance
what is TMS
tetramethylsilane
what is the concentration of moderately concentrated HCl
4moldm-3
what is the concentration of moderatetly concentrated NaOH?
2 moldm-3
how can high resolution mass spec be used to distinguish between compounds with same Mr?
High-resolution MS gives M+ peak (AW) to several decimal places
different compounds have different Mr values in the decimal places (AW)
atoms of the elements/C,O,H have Ar values that are not exact whole numbers
describe and explain how the structure of enzymes helps them to catalyse reactions
They have an active site
Substrate binds to the active site and reacts with lower EA
how do amino acids form zwitterions
internal acid base reaction
NH2
gains proton/H+
, OH loses proton
