When the experiments illustrated in the above figures were repeated, but insteea

Question

When the experiments illustrated in the above figures were repeated, but insteead of figa is essentially inchanged except that the rate of o2 consumption following the addition of Adp is decreased somewhat. How can you account for this and what do you expect the percent of decrease ( compared to the experiment with succinate to be? EXPLAIN.

2. Atpenin is a relatively new antifungal antibiotic produced by Penicillium. In order to investigate its mode of action the following experiments were preformed: A suspension of freshly-prepared mitochondria in phosphate buffer was incubated with various compounds and O2 consumption, measured with an oxygen electrode:

Explanation / Answer

When mitochondria are incubated in an oxygraph apparatus (oxygen electrode) in an isotonic medium containing substrate and phosphate buffer, then addition of ADP causes a sudden burst of oxygen uptake as the ADP is converted into ATP. ATP is broken down by ATPase activities contaminating the preparation, and the resulting ADP is then re-phosphorylated by the intact mitochondria.

With reference to the graph on addition of ADP the oxygen consumption decreased about 25 mM.

Hence the percent of decrease when compared to the experiment with succinate is 25/250 x 100 = 10 %.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.