Answer: C. At a pH of 8, the enzyme starts to denature and changes shape.
Explanation: The activity of the enzyme increases as the pH increases from 0 to 7 i.e in acidic medium but as the pH reaches 8, the enzyme activity starts decreasing which means the enzyme is not able to function properly.
The enzyme is made up of proteins which is composed of chain of amino acids. Thus in basic pH i.e pH above 8, the bonds of the amino acids break and the enzyme is said to get denatured as the shape of enzyme has changed.
The direct source of energy to move the sailboat is probably wind, since wind is what pushes the sail of the sailboat, which is what propels the sailboat forward.
The characteristic best distinguishes glycolysis and the Krebs cycle from the electron transport chain is the amount of ATP produced . In glycolysis net ATp production is 2 ATP and in 1 Kreb's cycle 38 ATP are produced. Hence option A is correct.