A) For each of the following statements determine if they are true (T) or false (F). • The primary active transport of H' via proton pump, establishes a proton gradient across the membrane. ISelect) • The intracellular pH is lower than the extracellular pH. Select] • Lactose transporter is an example of antiport. Select ) • Transport of lactose against its concentration gradient is entirely dependent on inflow of H" down their electrochemical gradient. ISelect)

A) For each of the following statements determine if they are true (T) or false (F). • The primary active transport of H' via proton pump, establishes a proton gradient across the membrane. ISelect) • The intracellular pH is lower than the extracellular pH. Select] • Lactose transporter is an example of antiport. Select ) • Transport of lactose against its concentration gradient is entirely dependent on inflow of H" down their electrochemical gradient. ISelect)

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter20: Electron Transport And Oxidative Phosphorylation

Section: Chapter Questions

Problem 22P

See similar textbooks

Similar questions

Many bacterial cells contain an ATP dependent H* transporter that pushes H* out of the cells. The ATP dependent H* pump hydrolyzes 1 ATP to ADP + P; each cycle. Assume that these cells maintain a cytosolic concentration of H* at 10 µM and that the exterior concentration is held at 1.50 mM, while have a resting membrane potential of -60.0 mV (defined for transport into the cytosol), and operate at 25 °C. What is the AGT (total free energy of transport) available to conduct work using the established H* gradient? -12.4 kJ/mol -6.6 kJ/mol -23.9 kJ/mol -18.2 kJ/mol
ATP + H20 → ADP + Pi AG = -30.5kJ/mol 3Na* (inside) + 2K* (outside) + ATP* + H20 → 3Na* (outside) + 2K* (inside) + ADP3 + Pi2 + H* Calculate the minimum pH difference across a membrane that could, theoretically at least, support he fromation of 1.0 mM ATP from Pi and 1.0 mM ADP at pH 7 at 25 degrees.
V-class proton pumps run backward relative to the F-class ATP synthase. Consider the cartoon, which shows the conformations of the beta-subunits and ATPIADP + Pj of the F-class synthase. Which of the following associations between the conformation of the beta subunit and ATP/ADP + P¡ is correct for V- Binding Change Mechanism loose binding ADP+P ATP ATP class pumps? C repeat ADP + P, ADP АТР tight binding АТР +P оpen АТР O The open conformation releases ATP. Hydrolysis of ATP to ADP + P¡ drives the change from tight to loose. O Binding of ADP + P¡ drives change from open to loose. Hydrolysis of ATP to ADP + Pj drives the change from open to loose.
A transmembrane protein helps catalyze the transport of solute A from the INSIDE TO the OUTSIDE of a cell. The reaction can be represented by the reaction coordinate diagram below. It is possible to conclude that the concentration of A on the outside of the cell is than its concentration on the inside AND that it is_ to expect that the protein will at some point form a continuous path between th cytosol and the extracellular environment. A inside A outside reaction coordinate O lower; reasonable O higher; unreasonable O higher; reasonable free energy
A bacterial lactose transporter, which is highly specific for lactose, contains a Cys residue that is essential to its transport activity. Covalent reaction of N-ethylmaleimide (NEM) with this Cys residue irreversibly inactivates the transporter. A high concentration of lactose in the medium prevents inactivation by NEM, presumably by sterically protecting the Cys residue, which is in or near the lactose-binding site. You know nothing else about the transporter protein. Suggest an experiment that might allow you to determine the Mr of this Cys-containing transporter polypeptide.
Intramitochondrial ATP concentrations are about 5 mM, and phosphate concentration is about 10 mM. If ADP is five times more abundant than AMP, calculate the molar concentrations of ADP and AMP at an energy charge of 0.85. Calculate AG for ATP hydrolysis at 37 °C under these condi- tions. The energy charge is the concentration of ATP plus half the concen- tration of ADP divided by the total adenine nucleotide concentration: [ATP] + 1/2[ADP] [ATP] + [ADP] + [AMP]
The toxic effect of Na+ ions can be avoided in some plant species by storing them in membrane-bound vacuoles within the cytosol. Calculate the maximum vacuolar-to-cytosolic [Na+] ratio that could be achieved by a Na+/H+ antiport mechanism in the vacuolar membrane if the cytosolic pH is 7.4 and the vacuolar pH is 5.6.
Intramitochondrial ATP concentrations are about 5 mM, and phos- phate concentration is about 10 mM. If ADP is five times more abundant than AMP, calculate the molar concentrations of ADP and AMP at an energy charge of 0.85. Calculate AG for ATP hydrolysis at 37 °C under these conditions. The energy charge is the concentra- tion of ATP plus half the concentration of ADP divided by the total adenine nucleotide concentration: [ATP] + 1/2[ADP] [ATP] + [ADP] + [AMP]
What is the energy requirement to transport 2 mol of K* across the membrane by the Nat-K+ ATPase transporter protein at 37 °C under conditions in which the membrane potential is 70 mV (the inside of the cell is negative relative to the outside) and the ion concentrations are as follows: [K+]outside = 5 mM [K+Jinside = 140 mM [Na loutside = 150 mM [Na+Jinside = 10 mM +1.83 kJ + 3.66 kJ O-1.83 kJ O-3.66 kJ
Phosphatidylserine (PS) is considered to be an intermediate in the biosynthesis of phosphatidylethanolamine (PE) in E. coli, yet PS is not found in appreciable amounts among E. coli membrane phospholipids. Because PS must be present in the membrane to serve as an intermediate, how might you explain its failure to accumulate to a significant extent? What kinds of experiments could test your proposed explanation?
Will rate ASAP Which of the following amino acid residues would not provide a side chain for acid-base catalysis at physiological pH? (Assume pK values of each amino acid are equal to the pK value for the free amino acid in solution.) I. leucine II. lysine III. aspartic acid IV. histidine A) I, II, III B) I, II C) I D) II E) I, III
Lysozyme is an enzyme that hydrolyzes bacterial cell wall polysaccharides. When this reaction is carried out in the presence of H218O, it is observed that there is retention of configuration at the C1 carbon of the D site sugar as shown below: Would this result suggest that the enzyme mechanism involves the direct nucleophilic attack of water at C1 or that the enzyme mechanism involves attack by a nucleophilic amino acid side chain of the enzyme that generates a transient covalent intermediate?