
Question 19 (2 points) Select all choices that apply The lac operon is activated by the...
The lac operon contains a DNA sequence known as the lac promoter (P or P+ for wild type; P– for mutant (RNA polymerase does not bind)) that serves as the RNA polymerase binding site. The lac operon also contains a DNA sequence known as the Lac operator (O or O+ for wild type; O– or Oc for mutant (lac repressor cannot bind)) which is the binding site for lac repressor. The lac repressor, a protein, is encoded by the lac...
1) The lac operon is… a) Positive repressible b) Both negative inducible and positive repressible c) Positive inducible d) Negative inducible 2) An activator regulatory protein… a) Is involved in negative regulatory control b) Is a cis acting regulatory element c) Recruits RNA polymerase to the promoter d) Prevents RNA polymerase from binding the promoter 3) For the lac operon, the presence of the substrate (lactose) activates the repressor. True or False? a) true b) false 4) cAMP… a) Activates...
Yet, all the cells in your body contain the same
genes (and same alleles). The difference across cell types
is that genes get selectively expressed (turned on or off)
based on the proteins needed for cellular function given their
environment.
Select which statement explains the reason why hair does not
normally grow on your muscle cells.
a.
Muscle cells have the gene for keratin, but do not express
it
b.
Muscle cells do not have the gene for keratin and...
Catabolite repression can regulate the expression of the lac operon in E. coli. In terms of this positive regulation of the lac operon: What is the activator? Would it work in cis or trans? What molecule binds to the allosteric domain of the activator? What influences strongly the levels of the molecule you answered for part b? To what regulatory sequence does the activator bind? What part/domain of the activator? What is the effect of this binding? Name the two...
Quiz 10 1. (2 points) Which of the following conditions would lead to the highest levels of lac operon expression? a) High lactose, high glucose b) High lactose, low glucose c) Low lactose, high glucose d) Low lactose, low glucose e) None of the above would have any lac operon expression 2. (2 points) Which of the following is true concerning molecular genetics? a) tRNA carries amino acids into the nucleus in eukaryotic cells b) DNA polymerase moves towards the...
Question 1 Match the term with the best definition or description; most topics relate to the regulation of gene expression. General type of protein which will increase transcription rates when it attaches to a site A. Factor connected to a particular gene - B. Co-repressor C. Enhancer D. Promoter E. Structural F. Intron G. Activator H. Operator I. Basal transcription J. Glucocorticoid receptor K. Sigma factor L. Mediator M. Inducer N. TATA box O. Repressor The rates of mRNA produced...
A) An Operon is:? 1- A gene that affect another gene transcription. 2. A gene coding for a metabolic pathway. 3. A protein that blockgene expression. 4. A set of genes under the control of one promoter. B )- In bacteria the Lac Operon genes code for proteins that break down.? 1- Arabinose 2- Lactose 3- Galactose 4- Glucose C )mRNA processing involves removal of .......? 1- Introns 2- The poly-A tail 3- The 5' cap 4- Exons D )...
A genetically engineered plasmid Ficarries all of the elements of the lac operon, but replaces the structural genes with the reporter gene green fluorescent protein (GFP). The repressor allele cannot bind lactose, and the OC allele cannot be bound by the repressor. Given the following genotypes and growth media that does not contain glucose, indicate in the table below whether you expect to see b-galactosidase activity and glowing green colonies of E. coli by selecting Yes or No. growth media...
The gene machine program shows you what happens when lactose is present in E. coli, and how the lac operon is under negative control. However, the lac operon is also under positive control from a protein called CRP, eAMP Receptor Protein. The absence of the lac repressor is essential but not sufficient for effective transcription of the lac operon. RNA polymerase also depends on the presence of CRP. Like the lac repressor, which can bind to the DNA and lactose....
Page < 2 > of 2 D. The trp operon would be expressed at high levels, comparable to its expression in the absence of trp 6. Based upon what you have learned about the E. coli trp operon, what could you say about expression of its structural genes in cells with large amounts of environmental trp, but expressing a mutant trp repressor that is unable to bind trp? A. The trp operon would be completely repressed due to the abundance...