Quiz 10 (BIO)
A template DNA strand contains 30%A, 20%T, 27%G, and 23%C. The RNA transcript contains: A. 30%A, 20%U, 27%G, and 23%C B. 30%T, 20%A, 27%C, and 23%G C. 30%A, 20%T, 27%G, and 23%C D. 30%U, 20%A, 27%C and 23%G
D. 30%U, 20%A, 27%C, and 23%G
*picture* Which of the mutations above would cause the synthesis of an incomplete (shorter than normal) version of the protein? A. mutation I B. mutation III C. none of the other answer options is correct D. mutation II
D. mutation II----ask about this one
UGU and UGC both code for cysteine. A change from UGU to UGC would thus be a _________ mutation. A. missense B. nonsense C. ambiguous D. silent E. none of the potential answers are true
D. silent
An mRNA sequence is 5'AUG-GGC-CAU-ACU-UAA3', where AUG is the start codon and UAA is the stop codon. How many distinct aminoacyl-tRNA synthases are required to translate the mRNA sequence? A. 4 B. 5 C. 2 D. 6 E. 3
A. 4----ask if start codon doesn't need to be translated
What process enables a single gene to encode two or more polypeptides that are different in their amino acid sequence? A. Alternative splicing B. Reverse transcription C. regulatory splicing D. capping E. self-splicing
A. alternative splicing
What is NOT a component of the translation machinery? A. protein polymerase B. ribosomes C. translation factors D. mRNA E. tRNA
A. protein polymerase
Assuming that transcription and translation both proceed from left to right, which is the correct orientation of the DNA template, the RNA transcript, and the protein product? A. DNA template 5'- ......... -3' RNA transcript 5'- ......... -3' Protein product H2N- ....... -COOH B. DNA template 3'- ......... -5' RNA transcript 5'- ......... -3' Protein product H2N- ....... -COOH C. DNA template 5'- ......... -3' RNA transcript 3'- ......... -5' Protein product HOOC- ....... ..-NH2 D. DNA template 3'- ......... -5' RNA transcript 5'- ......... -3' Protein product HOOC- ....... ..-NH2
B. DNA template 3'- ......... -5' RNA transcript 5'- ......... -3' Protein product H2N- ....... -COOH
Which of the following changes affects more than a single amino acid in a sequence? A. a silent mutation B. A missense mutation C. A frameshift mutation D. BOTH a silent mutation AND a missense mutation E. BOTH a missense mutation AND a frameshift mutation
C. a frameshift mutation
You are studying an individual with very low levels of insulin in her blood. Further analysis indicates that cells of her pancreas are producing normal levels of this protein, but most of it is accumulating in the cytoplasm rather than being secreted from cells. Which hypothesis to explain this observation makes the most sense? A. a chromosomal segment that includes the gene for insulin has been inverted B. A missense mutation has altered the ribosome-binding sequence at the 5' end of the mRNA C. A small deletion has removed the nucleotides that code for the signal sequence at the amino terminus of the protein D. A missense mutation has caused premature termination during translation of this protein E. A two-base deletion near the middle of the gene has altered the reading frame during translation of the protein
C. a small deletion has removed the nucleotides that code for the signal sequence at the amino terminus of the protein
What enzyme catalyzes the attachment of amino acids to tRNA molecules? A. topiosomerase B. translation factor C. amino-acyl tRNA synthase D. ribosome E. helicase
C. amino-acyl tRNA synthase
