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Course: HS biology (archived) > Unit 11

Lesson 1: Cellular respiration skill check

Skill check: Cellular respiration

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Skill check: Cellular respiration

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In a redox (oxidation-reduction) reaction, one or more electrons are transferred from one molecule to another.

In a redox reaction, the molecule that loses electrons is
, and the molecule that gains those electrons is
.

In one step of cellular respiration, the molecule succinate ( $C_{4} H_{6} O_{4}$ ‍) is converted to fumarate ( $C_{4} H_{4} O_{4}$ ‍) in the reaction:
$C_{4} H_{6} O_{4}$ ‍ $+$ ‍ $FAD$ ‍ $\to$ ‍ $C_{4} H_{4} O_{4}$ ‍ $+$ ‍ ${FADH}_{2}$ ‍
In the conversion of succinate to fumarate, which molecule is oxidized and which is reduced?
Oxidized
Reduced
$FAD$ ‍
$C_{4} H_{6} O_{4}$ ‍

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