You have isolated two mutations that show decreased expression of the Lac operon. However, unlike like the promoter mutations, these mutations don’t respond to the inducer IPTG. These mutations, designated Lac3– and Lac4–, are evaluated for the quantity of ß-galactosidase and permease activity expressed with or without IPTG:

 

Mapping experiments reveal that Lac3– and Lac4– are different short deletions located in the region before the start of the LacZ gene. Given the data shown above suggest which genetic element(s) in addition to part of the promoter has been deleted in each mutant. 

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#Question id: 11677

#SCPH28 | Zoology

Which of the following contribute to maintaining the high osmolarity of the renal medulla?

I) active transport of salt from the upper region of the ascending limb

II) the spatial arrangement of juxtamedullary nephrons

III) diffusion of urea from the collecting duct

IV) diffusion of salt from the descending limb of the loop of Henle

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#Question id: 11678

#I Life Science/ Life Sciences Group – I-V

Increased antidiuretic hormone (ADH) secretion is likely after ________.

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#Question id: 11678

#SCPH28 | Zoology

Increased antidiuretic hormone (ADH) secretion is likely after ________.

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#Question id: 11679

#SCPH28 | Zoology

After blood flow is artificially reduced at one kidney, you would expect that kidney to secrete more of the hormone known as ________.

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#Question id: 11680

#SCPH28 | Zoology

After drinking alcoholic beverages, increased urine excretion is the result of ________.

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#Question id: 11705

#SCPH28 | Zoology

Osmoregulatory adjustment via the atrial natriuretic peptide system can be triggered by: