Review Questions Flashcards
What would happen if a mutation changed a start codon to some other codon?
mRNA transcribed from mutated gene would be nonfunctional because ribosomes would not initiate translation.
What happens when one nucleotide is lost from the middle of a gene?
mRNA-reading of triplets downstream from deletion is shifted, leading to long sting of incorrect amino acids in the polypeptide.
Which organelle coordinates translation?
Ribosomes
Translation is the synthesis of […] with one […] determining each amino acid in the sequence.
Protein (polypeptides); codon
Transcription is the synthesis of […], using […] as a template.
mRNA; DNA
Which does my participate directly in translation?
1) ribosomes
2) tRNA
3) mRNA
4) DNA
DNA
What is an anticodon?
Base triplet of tRNA that couples tRNA to complementary codon in mRNA.
Base pairing of anticodon to codon is the key step in translating mRNA to a polypeptide.
Why is a final mRNA often shorter than the DNA that coded for it?
Introns are removed from the RNA.
How does RNA polymerase know where to start transcribing a gene?
It recognizes the gene’s promoter
What are transcription and translation?
Transcription-
Transfer of genetic information from DNA to RNA
Translation-
Use of info in an RNA molecule for the synthesis of a polypeptide.
How many nucleotides are necessary to code for a polypeptide that is 100 amino acids long?
300
3 nucleotides per 1 amino acid
