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2

The free energy change that you quote for the phosphoglycerate kinase (PGK) forward reaction is, of course, the standard free energy change (ΔG0') for the overall reaction. The standard free energy change is defined for all reactants at a concentration of 1M. Note that this value includes the formation of ATP - the free energy of hydrolysis of 1,3-BPG ...


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You have to look at the complete reaction including the cofactors. In general, you can drive a chemical reaction into directions which are not favorable by: removing products from the environment (if they are gaseous for example or react further) having a huge excess of substrates (and thus making the back reaction less likely to happen) and by coupling ...


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The term "irreversible" means that the reverse reaction occurs so rarely that it is considered negligible. This means that you do not have to consider equilibrium, as you have to for reversible reactions. Instead, you can assume that all of the reactants will eventually become product. As you stated, this is true for reactions that have a very negative ...


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I assume that you mean energy consumption. Talking in round numbers the daily energy requirement of a sedentary human is 2,500 kcal. It's usually said that the brain uses 20% of this energy. What does this mean in terms of power consumption? 500 kcal = 500 x 1000 x 4.2 J -[1] 24 h = 24 x 60 x 60 s -[2] 1 W = 1 J/s therefore brain power = ...


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Protons are pumped out of the bacterial cell by the electron tansport chain. This creates a protonmotive force with two components, one due to the difference in proton concentration, the other due to the membrane potential that is created. In bacteria and mitochondria it is the membrane potential component that provides most of the driving force to pull ...


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Bears recycle their urine while hibernating, unlike most other mammals.


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Hibernating bears have an ingeneous way of recycling their urine (urea) while they hibernate. Also turtles and frogs in the bottom of ponds deal in unique ways during hibernation.. This should get you started. recycling waste externally is done by rabbits who will pass pellets through their system twice, the firsttime to partially digest, the second time to ...


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If an organism recycles some material, by definition, it is not waste. Though some animals will eat feces.(For eg.Rabbits) It's a way to double-digest something that was not fully broken down or absorbed the first round.


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All organisms recycle their waste internally. Every cell of every living organisms is constantly breaking things down and re-using the components so produced. But you're presumably wondering about things such as carbon dioxide, urine and faeces? These are not recycled because the benefits of doing so are not worth the costs. Let's consider carbon dioxide as ...


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There can be many reasons for why proteins are chosen as building blocks. Apart from what Chris said, I would add some points: Amide bond in proteins is quite strong and thus provides a stable backbone Because of different amino acids proteins can be versatile Functionality comes first and then storage (assuming that initially there was just harvesting and ...


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First, it is a matter of the energy that food can provide. Here fat wins clearly (from the Wikipedia article on Food Energy): Fat: 37 kJ/g Ethanol (drinking alcohol): 29 kJ/g Proteins: 17 kJ/g Carbohydrates: 17 kJ/g Organic acids: 13 kJ/g Polyols (sugar alcohols, sweeteners): 10 kJ/g Fiber: 8 kJ/g Proteins and Carbohydrates have approximately the same ...



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