proteins Flashcards
describe an amino acid
amine group on the left NH2
carboxyl group on the right COOH
R group at the top
whats it called when two aminos join toghether
dipeptide
whats the bond inbetween two aminos
peptide
what happens in a condensation reaction
h2o is lost
what are proteins made up of
amino acids
Fibrous protein properties
Insoluble
Flexible
Strong
Elongated strands
What does TLC stand for
Thin layer chromatography
What are the two phases of chromatography
Stationary and mobile
where are DNA molecules foudn
in the nucleus
where are organelles that create proteins foudn
cytoplasm
why is DNA copied in synthesis
the original DNA is too nig to be moved out of the nucleus so its copied into mrna
what happens after DNA has been copied into mRNA
the mrna leaves the nucleus and joins with a ribosome in the cytoplasm where it can synthesise a protein.
In transcription what is broken between the 2 pairs
Hydrogen bonds
what breaks the hydrogen bonds between the 2 pairs
DNA helicase
desribe transcription in order
DNA helicase breaks H bonds between the two strands of a gene
complementary rna nucleotides move into and form H bonds with their complementary bases on the exposed DNA strand( the template strand)
RNA polymerase joins theRNA nucleotides by forming phospodiester bonds
Once the mRNA has been fully synthesised it detaches from the template strand and the DNA goes back to its normal double helix structure
The mRNA moves out of the nucleus via a nucleic pore and moves to the cytoplasm to begin translation…
describe translation in order following on from transcription
initially the small subunit of a ribosome binds to the mrna at the start codon
a tRNA molecule complementary to the start codon attaches and is held in place by hydrogen bonds
the next tRNA molecule attaches to the 2nd codon on the mRNA
A peptide bond forms between the two amino acids that have been coded for by the tRNA (energy is needed by ATP for the peptide bond to be created)
the third tRNA molecule attaches to the third codon and the first tRNA molecule leaves just the amino acid behind
the ribosome contiues to repeat this process, forming the polypetide chain until it reaches the end codon and it detaches, releasing the polypeptide chain
once the polypeptide chain is correctly folded it can then carry out its function in the cell
