BIOL 1010 Protein Synthesis

Define initiation in transcription

When RNA polymerase binds to a promoter which signals the unwinding of DNA; First step

A mutation within a gene that will insert a premature stop codon in mRNA would ______. A)result in a polypeptide that is one amino acid shorter than the one produced prior to the mutation B)result in a shortened polypeptide chain C)result in a missense mutation D)change the location at which transcription of the next gene begins E)have the same effect as deleting a single nucleotide in the gene

B

Define the following mutations in a polypeptide chain: 1)Missense 2)Silent 3)Frameshift 4)Nonsense

1) Missense = A single nucleotide changes effectively changing up the amino acid 2) Silent = A single nucleotide that changes but NOT changing the original amino acid. 3) Frameshift = A single nucleotide getting added or removed making the codons uneven (also possibly changing the amino acid) 4) Nonsense = Is where a STOP codon is suddenly gets processed shortening the polypeptide chain.

Transcription is the ______. A) manufacture of a strand of RNA complementary to a strand of DNA B)manufacture of two new DNA double helices that are identical to an old DNA double helix C)modification of a strand of RNA prior to the manufacture of a protein D)manufacture of a protein based on information carried by RNA E)manufacture of a new strand of DNA complementary to an old strand of DNA

A

Define RNA polymerase

An enzyme that unwinds DNA into RNA

How can a single RNA transcript be translated into different polypeptides? A) There is more than one way to modify the coded polypeptide. B)Two different genes can produce the same RNA transcript, which will then be translated differently. C) There is more than one way to splice an RNA transcript. D)It does so by varying the rate at which it is broken down in the cytoplasm. E)It does so by varying the length of its tail.

C

Which of the following enzymes is responsible for RNA synthesis? A)RNase B)RNA gyrase C)RNA helicase D)RNA ligase E)RNA polymerase

E

Translation converts the information stored in ______ to ______.

RNA, a polypeptide

Define termination in transcription

Section of DNA that tells the RNA polymerase to stop.

Define elongation in transcription

The process of adding the nucleotides to the RNA strand; Second Step

What kind of mutation is it when a single nucleotide is switched but it doesn't change the amino acid it codes for? a. Missense b. Silent c. Frameshift d. Nonsense

b. Silent Mutation

The correct sequence of events occurring during transcription is ______.

initiation, elongation, termination

Introns are ______.

noncoding DNA sequences

Where is translation accomplished?

ribosomes