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Study with Quizlet and memorise flashcards containing terms like How is chemical energy in glucose released?, Give the definition of Respiration., What is Aerobic respiration and Fermentation? and others.
Contains all of the biotic (living) and abiotic (non living) factors in an area, where they form a stable relationship
Oct 4, 2024 · Biology revision for biology A-Level on the effect of surface area. Learn with flashcards, games and more — for free.
The size of their surface, or surface area, defines how quickly they can absorb substances. The size of their volume defines how much of these substances they need.
- Overview
- Role of mitochondria
- Main metabolic processes
- Glycolysis
- Tricarboxylic acid cycle
- Oxidative phosphorylation
cellular respiration, the process by which organisms combine oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining activities and discarding, as waste products, carbon dioxide and water. Organisms that do not depend on oxygen degrade foodstuffs in a process called fermentation. (For longer treatment...
One objective of the degradation of foodstuffs is to convert the energy contained in chemical bonds into the energy-rich compound adenosine triphosphate (ATP), which captures the chemical energy obtained from the breakdown of food molecules and releases it to fuel other cellular processes. In eukaryotic cells (that is, any cells or organisms that p...
Biologists differ somewhat with respect to the names, descriptions, and the number of stages of cellular respiration. The overall process, however, can be distilled into three main metabolic stages or steps: glycolysis, the tricarboxylic acid cycle (TCA cycle), and oxidative phosphorylation (respiratory-chain phosphorylation).
Glycolysis (which is also known as the glycolytic pathway or the Embden-Meyerhof-Parnas pathway) is a sequence of 10 chemical reactions taking place in most cells that breaks down a glucose molecule into two pyruvate (pyruvic acid) molecules. Energy released during the breakdown of glucose and other organic fuel molecules from carbohydrates, fats, ...
The TCA cycle (which is also known as the Krebs, or citric acid, cycle) plays a central role in the breakdown, or catabolism, of organic fuel molecules. The cycle is made up of eight steps catalyzed by eight different enzymes that produce energy at several different stages. Most of the energy obtained from the TCA cycle, however, is captured by the...
In the oxidative phosphorylation stage, each pair of hydrogen atoms removed from NADH and FADH2 provides a pair of electrons that—through the action of a series of iron-containing hemoproteins, the cytochromes—eventually reduces one atom of oxygen to form water. In 1951 it was discovered that the transfer of one pair of electrons to oxygen results in the formation of three molecules of ATP.
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Oxidative phosphorylation is the major mechanism by which the large amounts of energy in foodstuffs are conserved and made available to the cell. The series of steps by which electrons flow to oxygen permits a gradual lowering of the energy of the electrons. This part of the oxidative phosphorylation stage is sometimes called the electron transport chain. Some descriptions of cellular respiration that focus on the importance of the electron transport chain have changed the name of the oxidative phosphorylation stage to the electron transport chain.
- The Editors of Encyclopaedia Britannica
Jan 15, 2021 · Cellular respiration is the process through which cells convert sugars into energy. To create ATP and other forms of energy to power cellular reactions, cells require fuel and an electron acceptor which drives the chemical process of turning energy into a useable form.
Oct 25, 2024 · Diffusion, process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration. A familiar example is the perfume of a flower that quickly permeates the still air of a room.
