1) When a de-coupler such as 2,4-DNP is added to a respiring mitochondrion, which of the following effects on the process of ETC-OP will be true, which will be false. a) Mitochondria no longer reduce O2 to H2 b) Electrons no longer enter the electron transport chain. c) Activity of Complex V (ATP Synthase) is greatly decreased. d) The P/O ratio for FADH2 becomes larger than the P/O ratio for NADH.

When the antibiotic X is added to actively respiring mitochondria, several things happen: the yield of ATP decreases, the rate of O2 consumption increases, heat is released, and the pH gradient across the inner mitochondrial membrane increases. Does X act as an uncoupler or an inhibitor of oxidative phosphorylation? Explain the experimental observations in terms of the antibiotic’s ability to transfer K+ ions across the inner mitochondrial membrane.

The enzyme dihydrofolate reductase (DHFR) normally resides in the cytosol, andDHFR can be imported into mitochondria by appending a mitochondrial signalsequence. However, when this modified DHFR is incubated with methotrexate, whichis a substrate analog that binds tightly to the active site, the modified DHFR is nolonger imported.a) Propose an explanation for why methotrexate prevents import of DHFR intomitochondria.b) Suppose that DHFR were modified instead by appending a nuclear localizationsignal. Would you expect methotrexate to prevent transport of this modified DHFRinto the nucleus? Why or why not?

In human cells, where does fatty acid elongation (that is, beyond the C16:0 normally produced by fatty acid synthase) occur?   a)On the outer (cytosolic) face of the outer mitochondrial membrane b)On the outer (cytosolic) face of the endoplasmic reticulum membrane c)Free in the cytosol d)In the mitochondrial matrix

Why is IMPDH in the mitochondria?

In electron transport, each of the following respiratory complexes is involved in the flow of electrons from NADH to O2 except   A) complex I. B) complex II. C) complex III. D) complex IV. E) All of the complexes are involved

1) If we put a photosynthetic organism in a closed, sealed environment and shine a light on it, we observe that the CO2 and O2 levels in the container reach constant levels. a) Explain why this would occur. b) What factor/value would you expect to be the primary determinant of this value?

Cyanide is a rapidly acting, potentially deadly chemical that can exist in various forms. If accidentally ingested or inhaled, cyanide can cause rapid death by binding to complex IV (cytochrome oxidase) of the electron transport chain in the mitochondria.   A.What is the mechanism by which cyanide stops cellular respiration? Be specific. B.Does cyanide cause an effect at the beginning or the end of the cellular respiration pathway? C.Does this make a difference on the effect that this chemical can have on our cells? Why? D.How does cyanide’s course of action affect the remainder of the cellular respiration pathway? E.If a person accidentally swallows cyanide, mention a potential treatment that is currently available. What is the mechanism of action of this treatment? Be specific. Please answer completely will give rating surely All questions answers needed

When pure reduced cytochrome c is added to carefully prepared mitochondria along with ADP, Pi, antimycin A, and oxygen, the cytochrome c becomes oxidized, and ATP is formed, with a P/O ratio approaching 1.0.(a) Indicate the probable flow of electrons in this system.(b) Why was antimycin A added?(c) What does this experiment tell you about the location of coupling sitesfor oxidative phosphorylation?(d) Write a balanced equation for the overall reaction (including cyt c oxidation and ATP synthesis).(e) Calculate ΔG°′ for the above reaction, using E′0 values from Table 14.1and a ΔG°′ value for ATP hydrolysis of -32.2 kJ/mol.

1) Which of the following contains all of the information required to target a precursor protein from the cytosol to the mitochondrial matrix? a. N-terminal uptake-targeting sequence b. C-terminal uptake-targeting sequence c. post-translational organelle d. translocon e. None of the above 2) In the absence of targeting information, what is the default location of proteins synthesized on cytosolic ribosomes? a. Golgi apparatus b. ER lumun c. Cytosol d. Cell plasma membrane e. ER membrane