The lac operon - Study guides, Class notes & Summaries

What will be the effect on transcription when an inhibitor is in play? A. Allow transcription B. Prevent transcription - Answer-B Explanation: An inhibitor prevents activator from binding to DNA; activators are used in positive regulation (increasing transcription) - thus, the inhibitor prevents the activator from positive regulating (increasing) transcription. What will be the effect on transcription when an inducer is in play? A. Allow transcription B. Prevent transcription - Answer-A Ex...

What is the first mRNA processing step? - ANSWER 5' capping Different mRNAs are made from the same initial pre-mRNA by ________. - ANSWER alternative splicing RNA transcription begins at a ________. - ANSWER promoter ________ protect(s) the pre-mRNA molecule. - ANSWER the 3' poly-a tail The process of pre-mRNA splicing removes ________. - ANSWER introns Spliced ________ differ in their exons. - ANSWER mRNAs Identify the three phases of transcription. - ANSWER initiation, elongation, te...

Bio 101 Chapter 7 Exam Questions and Answers All Correct A change in a cell's DNA sequence is Select one: a. transcription. b. a mutation. c. an operon. d. translation. e. replication. - Answer-b. a mutation A diploid cell only has two copies of most genes, but can make hundreds of copies of a protein from those genes per second because Select one: a. while transcription can repeat and make multiple mRNA copies of genes, and multiple ribosomes can translate the same mRNA. b. mul...

BIO 13 Practice Test 40 Questions with Verified Answers RNA contains the sugar a. ribose. b. deoxyribose. c. glucose. d. lactose. - CORRECT ANSWER a. ribose. Unlike DNA, RNA contains a. adenine. b. uracil. c. phosphate groups. d. thymine. - CORRECT ANSWER b. uracil. Which of the following are found in both DNA and RNA? a. ribose, phosphate groups, and adenine b. deoxyribose, phosphate groups, and guanine c. phosphate groups, guanine, and cytosine d. phosphate grou...

The fundamental units of heredity are known as _____ and multiple versions of them are known as _____ . Correct Answer genes; alleles Which of the following best describes a typical prokaryote chromosome? Correct Answer circular, composed of DNA Genes with different information at the same locus are called: Correct Answer alleles What is typically the difference between the bacterial chromosome and a plasmid? Correct Answer The chromosome contains genes that are essential for survival, ...

operon - Answer a series of genes whose expression is co-regulated by controlling their common mRNA transcript lacZ gene - Answer structural gene in lac operon which codes for beta-galactosidase, to break down beta-galactosides (which includes lactose) into glucose and galactose lacY gene - Answer structural gene in lac operon which codes for permease, which transports beta-galactosides into the cell. permeases are membrane bound lacA gene - Answer structural gene in lac operon which co...

Coupled transcription and translation - Ribosomes bind mRNA while mRNA is still being created, so that translation begins while transcription is still occurring - Advantage of lacking a nucleus Translation initiation - - Initiation factors bind ribosome to the ribosome binding site known as the Shine Delgarno sequence (AGGAGG) - Begins at start codon 1. 30s subunit binds mRNA 2. IF2 interacts with initiator tRNA 3. fMet-tRNA binds to start codon 4. Association of initiator tRNA with ...

Genetics Second Exam Practice Test 150 Questions with Verified Answers Which organism has polycistronic mRNA? (eukaryotic or prokaryotic) - CORRECT ANSWER Prokaryotic Do prokaryotes undergo splicing/processing? - CORRECT ANSWER No Where are attenuater sequences found? (what type of organism and what class of operons?) - CORRECT ANSWER In prokaryotic amino acid operons Do prokaryotic mRNA ALWAYs encode trans-acting factors? - CORRECT ANSWER No Which of the following statements is t...

BIO 214 EXAM 3 Practice EXAM 57 Questions with Verified Answers In the lac operon, CAP binding to the CAP site of the promoter ____. a. occurs when glucose is present b. inhibits RNA polymerase from binding to the promoter c. occurs when cAMP is absent d. helps the repressor protein bind to the operator e. enables RNA polymerase to transcribe the operon's genes - CORRECT ANSWER enables RNA polymerase to transcribe the operon's genes Gene regulation in both prokaryotes and eukaryotes...

Genetics Exam 2 practice exam 107 Questions with Verified Answers In five Hfr strains, each of which was used to build a time-of-entry map, the genes entered the recipient cells as follows: Strain 1: S L A C T F Strain 2: N P F T C A Strain 3: T F P N U Y Strain 4: S H Y U N P Strain 5: U N P F T C Which of the following represents a correct compilation of these results? A) S L A C T F P N H C U B) N P F T S L A C H U T C) T C A L S P N U Y H D) U N P F T C A L S T F E) S L A C T F...