Which of the statements below best describes the mechanism of proton translocation via a redox-driven conformational change?

a. matrix-derived protons are translocated across the mitochondrial membrane by altering pka values of functional groups located on the inner and outer faces of the membrane.

b. the flow of coenzyme q between complex i and complex iii alters membrane fluidity, which makes the membrane briefly permeable to proton

c. when the e- binds to cytochrome c, it results in dissociation of cytochrome c from complex iii, which stimulates release of h+ from complex iii.

Matrix-derived protons are translocated across the mitochondrial membrane by altering pKa values of functional groups located on the inner and outer faces of the membrane.

Explanation:

The translocation of protons occurs across the inner mitochondrial membrane by two mechanisms. This dislocation occurs with the electron transport system protein complexes.  The two mechanisms are described below.

First one is the redox loop mechanism. In this mechanism a redox reaction takes place. The separation of  H+ and e- thereby resulting in the electron transport system protein. The opposite side of inner mitochondrial membrane is the place where it gets deposited.

Next one is the proton pump mechanism. Here the translocation of matrix-derived protons take place on the inner mitochondrial membrane . this takes place with the alteration of pKa values of functional groups that have the location the inner and outer faces of the membrane.

when 25.0 ml of 0.700 mol/l naoh was mixed in a calorimeter with 25.0 ml of 0.700 mol/l hcl, both initially at 20.0 °c, the temperature increased to 22.1 °c. the heat capacity of the calorimeter is 279 j/°c.

the equation for the reaction is:

naoh + hcl → nacl + h₂o

moles of hcl = 0.0250 l hcl ×

0.700

mol hcl

1 l hcl = 0.0175 mol hcl

volume of solution = (25.0 + 25.0) ml = 50.0 ml

mass of solution = 50.0 ml soln ×

1.00

ml soln

= 50.0 g soln

δt=t2-t1

= (22.1 – 20.0) °c = 2.1 °c

the heats involved are

heat from neutralization + heat to warm solution + heat to warm calorimeter = 0

q1+q2+q3=0

nδh+mcδt+cδt=0

0.0175 mol ×

δh

+ 50.0 g × 4.184 j·g⁻¹°c⁻¹ × 2.1 °c + 279 j°c⁻¹ × 2.1 °c = 0

0.0175 mol ×

δh

+ 439.32 j + 585.9 j = 0

0.0175 mol ×

δh

= -1025.22 j

δh=1025.22j0.0175 mol= -58 600 j/mol = -58.6 kj/mol

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.