Which inner membrane protein directly catalyzes the reduction of o2 to h2o?

The correct answer is: Cytochrome oxidase

Cytochrome oxidase is an inner membrane protein part of the electron transport chain (Complex IV). It receives an electron from each of four cytochrome c molecules, and transfers them to O2, converting it to water. Cytochrome oxidase contributes to formation of proton electrochemical potential: it binds 4 H+, and translocates another 4 H+ across the membrane, increasing the transmembrane difference of proton electrochemical potential. This gradient is used for the ATP synthesis by ATP synthase.

answer-

the statement that f(x) = |x+a| + b has exactly one x-intercept is sometimes correct.

solution-

it solely depends on b, whether the function will have one or two or zero x intercept.

this plot of the given function, f(x) = |x+a| + b will be the basic absolute value graph i.e v shape, with vertex translated to (-a, b), instead of origin.

1-   if b is zero, the graph will have exactly one x-intercept, at x= -a

2- if b is positive, the whole graph will be above the x-axis, hence it will have no x-intercepts.

3- if b is negative, the graph will be below the x-axis, hence it will have two x-intercepts.

∴ the statement is sometimes true.