The Aeroschmidt Weed Contains an ATP-Driven Ion Pump in Its

question 10

Essay

The Aeroschmidt weed contains an ATP-driven ion pump in its vacuolar membrane that pumps potentially toxic heavy metal ions such as Zn²⁺ and Pb²⁺ into the vacuole.The pump protein cycles through a phosphorylated and an unphosphorylated state and works in a similar way to the Na⁺-K⁺ pump of animal cells.To study its action, you incorporate the unphosphorylated form of the protein into phospholipid vesicles containing K⁺ in their interiors.(You ensure that all of the protein molecules are oriented such that their cytosolic domains face the outside of your vesicles.) When you add Zn²⁺ and ATP to the solution outside such vesicles, you find that Zn²⁺ is pumped into the vesicle lumen.You then expose vesicles containing the pump protein to the solutes shown in Table 12-28. $\begin{array}{ccccc}&A&B&C&D&E&F\\\hline \text { Outside }&\mathrm{Zn}^{2+}+\text { ATP }&\mathrm{Zn}^{2+}&\mathrm{Zn}^{2+}+\text { ATP }&\mathrm{Zn}^{2+}&\text { ATP }&\text { ATP }\\\text { Inside }&K^+&&&K^+&&K^+\end{array}$
Table 12-28
You then determine the amount of phosphorylated and unphosphorylated ATP-driven ion pump protein in each sample.Your results are summarized in Table 12-28A, where a minus sign indicates an absence of a type of protein and a plus sign indicates its presence. $\begin{array}{llll}&A&B&C&D&E&F\\\hline \text { Phosphorylated }&+&-&-&-&-&++\\\text { protein present }\\\text { Unphosphorylated }&++&++&++&++&++&-\\\text { protein present }\end{array}$
Table 12-28A
You treat vesicles as in lane F, but before determining the phosphorylation state of the protein, you wash away the outside buffer and replace it with a buffer containing only Zn²⁺.What do you expect to happen in this sample, and what are the results you expect to observe with respect to phosphorylation and movement of K⁺?

Familiarize with methods and criteria for evaluating leadership effectiveness in nonprofits.

Understand the role of leadership in strategic planning and change management within nonprofit organizations.

Understand the fundamental concepts of classical conditioning.

Describe the preparedness hypothesis and its implications for conditioned learning.

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Definitions:

Fixed Manufacturing Cost

Expenses that do not change with the volume of production, such as rent, salaries, and insurance costs related to manufacturing facilities.

Relevant Range

The range of activity within which the assumptions about fixed and variable cost behaviors hold true.

Variable Cost

Costs that vary directly with the level of production or service provision, such as materials, labor, and utilities consumed in the production process.

Total Variable Cost

The sum of all costs that vary directly with the level of production or output, including materials and labor.