C1.1 HL Generating Heat
No description yet. This curated deck is ready for daily study.
Card preview (10)
Why do metabolic reactions produce heat?
Energy transfer between reactants and products is not 100% efficient — some potential energy in chemical bonds becomes heat energy.
What is metabolism?
The sum of all enzyme-catalysed reactions in cells — requires energy input > energy loss to sustain life.
What is the role of ATP in energy transfer?
ATP acts as a universal energy carrier, transferring chemical energy for metabolic reactions.
What happens when ATP is hydrolysed?
The energy released from breaking the phosphate bond powers cellular work and releases additional heat.
How is this heat energy useful?
It maintains body temperature for optimal enzyme activity (especially in endotherms).
How does cellular respiration generate heat?
During glycolysis, Krebs cycle, and electron transport, energy from glucose is used to make ATP; excess energy is lost as heat.
Why do enzymes have an optimal temperature?
Because molecular collisions occur fastest at this point; above it, enzymes denature, below it, reactions slow down.
Give examples of optimal temperatures.
Mammals ~38°C, birds ~40°C, reptiles ~24–35°C, thermophilic bacteria much higher.
What is endothermy?
The ability to generate body heat metabolically, e.g. birds and mammals.
Why do endotherms have high energy demands?
To maintain homeostasis via constant metabolic heat production requires continuous respiration.