Your cells are like tiny factories that need constant energy...
Biology3 views·Updated Jun 18, 2026·2 pagesUnderstanding Energy Carriers
K
Keira Kennedy McGrath@keirakennedymcg
1
of 2
Understanding Energy Carriers and Redox Reactions
Ever wonder how your body actually uses the energy from food? It all comes down to oxidation-reduction reactions (or redox reactions for short). These are chemical processes where electrons get passed around between molecules.
Oxidation means losing electrons, whilst reduction means gaining electrons. Remember this with the acronym OILRIG: Oxidation Is Loss, Reduction Is Gain. Your body uses these reactions constantly because they're brilliant at transferring energy efficiently - converting chemical energy from food into heat, movement, and even sound.
Energy carriers are the key players here. They directly participate in your body's metabolic reactions by either gaining high-energy electrons (reduction) or losing electrons after they've given up their energy (oxidation). Think of them as the delivery trucks moving energy around your cells.
Quick Tip: Redox reactions happen millions of times per second in your body right now - they're what keep your heart beating and your brain thinking!
2
of 2
The Main Energy Carriers: ATP, ADP, NAD+, and NADP+
ATP (adenosine triphosphate) is literally the energy currency of every cell in your body. It's made up of adenine, ribose, and three phosphate groups. When ATP breaks down into ADP + phosphate + energy, it releases the power needed for everything from nerve impulses to muscle contractions.
ADP (adenosine diphosphate) has just two phosphate groups instead of three. When your cells burn calories from food, they use that energy to stick another phosphate onto ADP, rebuilding it back into ATP. It's like recharging a battery.
NAD+ and NADP+ are electron carriers that work like shuttles. NAD+ is crucial during aerobic respiration - it picks up electrons and hydrogen ions to become NADH, then delivers them to the electron transport chain where they release energy to make more ATP. NADP+ does similar work during photosynthesis in plants.
Memory Trick: Think of ATP as your cell's rechargeable battery and NAD+/NADP+ as the charging cables that help move energy around!
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Biology3 views·Updated Jun 18, 2026·2 pagesUnderstanding Energy Carriers
K
Keira Kennedy McGrath@keirakennedymcg
Your cells are like tiny factories that need constant energy to keep you alive, and they use special molecules called energy carriers to move this energy around efficiently. These carriers work through oxidation-reduction reactions, which are basically fancy ways of...
1
of 2
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Understanding Energy Carriers and Redox Reactions
Ever wonder how your body actually uses the energy from food? It all comes down to oxidation-reduction reactions (or redox reactions for short). These are chemical processes where electrons get passed around between molecules.
Oxidation means losing electrons, whilst reduction means gaining electrons. Remember this with the acronym OILRIG: Oxidation Is Loss, Reduction Is Gain. Your body uses these reactions constantly because they're brilliant at transferring energy efficiently - converting chemical energy from food into heat, movement, and even sound.
Energy carriers are the key players here. They directly participate in your body's metabolic reactions by either gaining high-energy electrons (reduction) or losing electrons after they've given up their energy (oxidation). Think of them as the delivery trucks moving energy around your cells.
Quick Tip: Redox reactions happen millions of times per second in your body right now - they're what keep your heart beating and your brain thinking!
2
of 2Sign up to see the content. It's free!
- Access to all documents
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The Main Energy Carriers: ATP, ADP, NAD+, and NADP+
ATP (adenosine triphosphate) is literally the energy currency of every cell in your body. It's made up of adenine, ribose, and three phosphate groups. When ATP breaks down into ADP + phosphate + energy, it releases the power needed for everything from nerve impulses to muscle contractions.
ADP (adenosine diphosphate) has just two phosphate groups instead of three. When your cells burn calories from food, they use that energy to stick another phosphate onto ADP, rebuilding it back into ATP. It's like recharging a battery.
NAD+ and NADP+ are electron carriers that work like shuttles. NAD+ is crucial during aerobic respiration - it picks up electrons and hydrogen ions to become NADH, then delivers them to the electron transport chain where they release energy to make more ATP. NADP+ does similar work during photosynthesis in plants.
Memory Trick: Think of ATP as your cell's rechargeable battery and NAD+/NADP+ as the charging cables that help move energy around!
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