Topic 7 - Protien Synthesis (Paper 2) Flashcards
what does DNA control in a cell?
the production of proteins in a cell
what are proteins made up of?
chains of molecules called amino acids
why does every protein have a different function?
amino acid chains fold up to give each protein a different, specific shape
what are amino acids coded for?
a sequence of three bases in the gene. this is called a codon
how do amino acids make proteins?
amino acids are joined together to make proteins, following the order of bases in the gene
why does each gene code for a particular protein?
each gene contains a different sequence of bases, so codes for a particular protein
what is a non-coding region?
a region of DNA that doesn’t code for any amino acids
where are proteins made?
in ribosomes
what is the structure of mRNA?
It’s made up of a sequence of bases and is single-stranded. it also uses uracil instead of thymine as a base
what happens in transcription?
RNA polymerase binds to a region of non-coding DNA in front of a gene
the two DNA strands unzip and the RNA polymerase moves along one of the DNA strands
it uses the coding DNA in the gene as a template to make the mRNA. mRNA is complementary to the gene
once the mRNA is made it moves out of the nucleus and joins with a ribosome in the cytoplasm
what happens in translation?
amino acids are brought to the ribosome by tRNA
the order in which the amino acids are brought to the ribosome matches the order of the codons in mRNA
tRNA contains anticodons, which are complementary to the codon for the amino acid. the pairing of the codon and anticodon makes sure that the amino acids are brought to the ribosome in the correct order
the amino acids are joined together by the ribosome, making a protien
