Question

6:35 5 minutes ago 25) Which of the following turns off transcription by binding to the operator? A) repressons B) lactose C) RNA polymerase D) promoters E) enzymes 25) 26) In bacteria, what name is given to a cluster of genes with related functions, along with their control 26) A) exon B) operon C) promoter D) activator E) regulatory gene A mutant bacterial cell has a defective aminoacyl synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The 27) consequence of this for the cell will be that roteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU cell will compensate for the defect by attaching phenylalanine to tRNAs with B) the will occur; the cell will recognize the error and destroy the tRNA. C) none of the options D) the ribosome will skip a codon every time a UUU is encountered. E) none of the proteins in the cell will contain phenylalanine. called the TATA box, is said to be highly conserved in evolution. Which of 28) A part of the the following might this illustrate? A) The sequence evolves very rapidly B) The sequence does not mutate. C) The sequence is found in many but not all promoters D) Any mutation in the sequence is selected against E) The sequence is transcribed at the start of every gene. Repressors act by blocking the binding ofto the operator. A) DNA polymerase B) RNA polymerase C) regulatory genes D) promoters E) the operon 29) r triplet of bases in the template strand of DNA is S AGT 3. The corresponding codon 30) for the mRNA transcribed is A) 3 UGA 5 B) 5 TCA 3 C)3 UCA 5 D)3 ACUS Eleither UCA or TCA, depending on wobble in the first base E) either UCA

Answer 1

25) 25) Waich of the following turms off tanscription by binding to the operator? A) repressors B) lactose C) RNA polymerase D) promoters E) enzymes 26) In bacteria, what name is given to a cluster of genes with related functions, along with their control sequences? 26) exon C) p D) activator E) regulatory gene A mutant bacterial cell has a defective aminoacyl synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The consequence of this for the cell will 27) be that A) proteins in he cell will ndlude lysine instead of phenylalanine at amino acid positions fied by the codon UUu ne to tRNAs with lysine-specifying anticodons. C) none of the options D) the ribosome will skip a codon every time a UUU is encountered. E) none of the proteins in the cell will contain phenylalanine. will occur; the cell will recognize the error and destroy the tRNA. called the TATA box, is said to be highly conserved in evolution. Which of 28) A part of the the following might this illustrate? A) The sequence evolves very rapidly B) The sequence does not mutate. The sequence is found in many but not all promo mutation in the sequence is selected against t ot every gene. D) Any Repressors act by blocking the binding ofto the operator. A) DNA 29) D) promoters E) the operon for the mRNA transcribed ise correspondins t A) 3 UGA 5 r triplet of bases in the template strand of DNA is S AGT 3. The codon 30) 3' UCA 5 UCA or TCA, depending on wobble in the first base.