ScienceVerseLearning path: Respiration
The concepts to learn before Respiration, in order. Each step links to its page and, where one exists, its quiz.
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Your path
- CellDirect prerequisite
The basic structural and functional unit of all known living organisms. Every living thing is made of one or more cells, each bounded by a membrane and containing the machinery needed to grow, respond to its environment, and reproduce. Cells fall into two broad types: prokaryotic cells (such as bacteria), which lack a nucleus, and eukaryotic cells (such as those in plants, animals and fungi), which organise their DNA inside a membrane-bound nucleus.
- EnergyDirect prerequisite
The capacity to do work, taking forms such as kinetic energy (associated with motion) and potential energy (associated with position or configuration, such as height in a gravitational field). The total energy of an isolated system is conserved: energy changes form but is never created or destroyed.
- RespirationYour goal
Cellular respiration is the set of chemical pathways by which cells break down food molecules such as glucose to release energy in a usable form, ATP. With oxygen, it can be summarised as C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O and runs through glycolysis, the citric acid cycle and the electron transport chain; about 90 percent of the ATP comes from chemiosmosis in mitochondria. Without enough oxygen, cells fall back on fermentation, which yields far less ATP.