Protein synthesis Flashcards
What does the order of bases in DNA code for?
The order of amino acids in a protein
Why is the order of amino acids in a protein important?
Because the order of amino acids determines the shape of the protein
What are the two stages of protein synthesis called?
Transcription and translation
Where in the cell does protein synthesis take place?
Ribosomes (and some in nucleus)
what is mRNA?
Messenger RNA. mRNA moves the genetic code from the nucleus to ribosomes
Is mRNA single stranded or double stranded?
single stranded
Which 4 bases are present in mRNA?
Adenine (A), Uracil (U) ,Guanine (G), Cytosine (C)
What does RNA do during protein synthesis?
binds to DNA and produces a complementary mRNA strand from the DNA sequence
Where is mRNA synthesised?
In the nucleus
How many bases on the mRNA code for a single amino acid?
3 (a triplet code)
which type of RNA transfers amino acids to the ribosome to be made into protein?
tRNA (transfer RNA)
What are the main stages in transcription?
- RNA polymerase binds to non-coding DNA located in front of a gene
- RNA polymerase produces a complementary mRNA strand from the coding DNA of the gene
- The mRNA leaves the nucleus
What are the main stages in translation?
- mRNA travels from the nucleus and attaches to a ribosome
- A triplet of bases (a codon) on the mRNA codes for a specific amino acid.
- Amino acids are brought to the ribosome by tRNA
- The amino acids are joined together to make a protein.
What is the purpose of coding DNA?
Provide genetic code for synthesising protein
What is the purpose of non-coding DNA?
Switches genes on and off by causing or preventing binding of RNA polymerase
