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