Protein Synthesis Flashcards
Describe how mRNA is produced thru transcription
• H bonds are broken to seperate DNA strands
• DNA helicase
• only template strand used to make mRNA
• complimentary base pairing occurs
• adjacent RNA nucleotides join by RNA polymerase
• pre-mRNA formed
• introns removed to form mRNA (splicing)
The difference in structure between DNA and RNA
larger|smaller
double stranded|single stranded
thymine|uracil
deoxyribose|ribose
Difference in structure between DNA and mRNA
base pairs|doesnt
introns|doesnt
Describe how translation leads to the production of polypeptides
• ribosomes attach to mRNA
• ribosomes find the start codon
• tRNA carries a specific aa
• anticodon on tRNA is complimentary to codon on mRNA
• ribosomes move along to next codon
• process repeated joining correct aa by peptide bonds for polypeptides
• use energy from ATP
Difference between mRNA and tRNA
longer|shorter
straight|clover-leaf shaped
no base pairs|some
no aa binding site|aa binding site
no anticodon|anticodon
many|few
Why is the percentage of bases from the middle and end of the chromosome different?
• different case sequences
• pre-mRNA transcribed from different DNA
How can a molecule stop protein synthesis ?
• bonds to codon on mRNA so tRNA won’t fit
• aa can’t join
What is the role of RNA polymerase in transcription?
• join adjacent nucleotides to form phosphodiester bond
What is the role of tRNA in translation?
• anticodon complimentary to codon on mRNA
• carries specific aa to ribosome
• correct sequence of aa along polypeptide
State two differences in location of translation in prokaryotic and eukaryotic cells?
• pro: occurs in smaller ribosomes
• doesn’t use rough ER
State the difference between transcription in prokaryotes and eukaryotes
• pro: no pre-mRNA formed
• doesn’t occur in nucleus
What do stop sequences do? (2)
-stop translation
-ribosome detaches from pp chain
Suggest one explanation for the faster rate of plasmid replication in sales going in a culture with a high amino acid concentration(2)
-Amino acids used in protein synthesis
- more DNA polymerase
