Regulation in bacteria and phages includes a number of exotic terms with which you can amaze/alarm your friends. Twelve terms are given below followed by twelve statements. Write the letter of the correct term. A single letter is sufficient. Not all letters need to be used, and a particular letter may be used more than once. (15 points)

Term list:

1. temporal control

2. positive control

3. negative control

4. inducible

5. non-inducible

6. repressible

7. constitutive

8. operator

9. repressor

10. effector molecule

11. feedback inhibition

12. suppressor mutation

13. 1. Phenotype with respect to beta-galactosidase synthesis for the partial diploid I+ O+Z+/I- Oc Z-     

___________

2. Phenotype of I+O+Z-/I+Oc Z+

___________

3. Phenotype of I+O+Z-/I-OcZ-

___________

4. Phenotype with respect to synthesis of tryptophan enzymes in the trp operon trpR+ Oc S+ (trpR codes for the repress, S=structural genes).

_______

5. Phenotype of trpR+ O+ S+ in the presence of tryptophan.

________

6. Regulatory molecule must be present at site in DNA (such as promoter) so that transcription can occur ____________.

7. Small molecules that bind to regulatory molecule such as repressor__________

8. Mutation that reverses effect of another mutation at a different site.

____________

9. Type of operons responding to catabolite repression (glucose effect).

___________

10. Post-translational control of biosynthetic pathway.

___________

                    11. Regulatory molecule that binds to operator region in DNA.

13. Describe one supportive measure for severe ARDS.

The parents of a 4-year-old boy explain to the clinic nurse that for weeks the child has been irritable and listless and even though he has developed a poor appetite, has gained weight. What signs and symptoms should the nurse look for, and what condition should the nurse suspect? What nursing interventions and parent education are appropriate?

11. Outline the general stages of a development cycle of a vaccine.

1. For food to pass into the stomach, it needs to pass through two sphincters. What are these two, What is the function of the second one (as in, the second sphincter the food would go through)? If this sphincter does not function properly, what medical issue could result?

Why are protein differ from one another in sugar content and structure ?

Give three reasons why chemical difference affects the 2D gel behaviour of the isoforms present.

I remember the professor telling the class LacZ and LacY both are not inducible. Maybe one of them is but not both. Please help explain.

For each of the E. coli strains containing the lac operon alleles listed, indicate whether the strain is inducible, constitutive, or unable to express ?-galactosidase and permease. Provide an explanation for your prediction

C. I+ O+ Z- Y+ / I? O^c Z+ Y?

9. List therapeutic options for COVID-19 currently under investigation.

If you made mice homozygous for loss-of-function mutations in Crx would you expect the level of GADD transcription to increase or decrease (relative to wildtype/normal)? Would GADD be the only gene affected by the loss-of-function Crx mutation or would the transcriptional levels of other genes change as well? Explain your answer.

Which of the following changes leads to an increase in entropy of the system?

The evaporation of water from a puddle

The freezing of water into an ice cube

The formation of starch from glucose molecules

The digestion of protein into amino acids

None of these

Explain how an E. coli cell that is deficient for proline synthesis (pro-) could become pro+ through the process of transduction.

• What determines protein structure?
• Describe the experiment that lead to this conclusion?
• What type of chemical interactions are involved in the tertiary protein structure?

Retinitis pigmentosa is a genetic disease that causes the breakdown and loss of retinal cells. Retinitis pigmentosa often starts with decreased night vision and will progress to blindness as retinal cells die.

Several genes have been linked to Retinitis pigmentosa, one of which is GADD. Mice lacking GADD (these mice were experimentally created so that the GADD region of the genome was deleted) have increased expression of non-retinal genes in retinal cells. In other words, in these mutant mice, genes that are not normally expressed in the retina are expressed.  

Crx is a key retinal transcription factor. Crx binds regulatory elements called CBRs (Crx-binding regions). GADD has two CBRs, one immediately proximal to the transcription start site (TSS), and one a few hundred base pairs downstream of the TSS.

You have received DNA from three patients with Retinitis pigmentosa. From the DNA, you sequence the GADD gene and its proximal/core promoter region.   

None of the patients have mutations in the coding region of GADD. All of the mutations you find are in the CBRs. Your findings are below:

• Patient 1 – Mutation in CBR1
• Patient 2 – Mutation in CBR2
• Patient 3 – Mutation in CBR1 and CBR2

How can mutations in non-coding regions cause a change in phenotype (in this case leading to retinitis pigmentosa)? Note: you do not have to give all possible reasons, explanations of one or two ways mutations in non-coding regions can have phenotypic effects is sufficient.