So i understand that enzymes lower a substrates required activation

>>7710879
It all depends if the reactuon first starts in the presence or absence of oxygen to obtain the energy. If there is a lack of oxygen the energy produced is very low and has the byproduct lactic acid as you know. This energy drives the pathway to begin in zero and first order kinetics. The enzyme uses the energy to quickly break the bonds of a substance. I hope this helps.

>>7710901
that did not help at all. what does areobic or anerobic conditions have to do with enzyme activity? i'm talking about their activity in the context of the human body. We are not talking about gylcogenisis or glyconeogenisis or metabolism. ..

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>>7710879
It comes from weak interactions between the enzyme and the substrate, such as Van der waals etc.
The activation site on the enzyme provides an ambient that stabilizes, using these interactions, the transition state of the reaction.
So the probability of the reaction going from either sides is more balanced, requiring less energy to push the transition state to the products.
The key thing is to understand that the enzyme is specific to the transition state, not to the substrate or the product.

>>7710879
The energy of reaction is the same regardless, and the reaction will proceed forward regardless towards products whether there is an enzyme or not (until equilibrium is reached, but in biochemistry, you can consider build of products to be case-by-case or used to shut down a reaction for a given purpose so don't worry about equilibrium). The difference is, a higher activation energy will create a larger energy-barrier that simple mass-action (more reactants vs. products) won't overcome in a timely manner. Enzymes are diverse and use all sorts of "tricks" to overcome energy activation, such as forming high-energy bonds which can be broken in a later reaction step (to push or pull the reaction forward), or as mentioned >>7710989 here, coax a reactant into the right conformation to gain some degree of reactivity. You're right that there is no "free energy," but enzymes are very good at allocating energy from parts of the system that wouldn't be in play otherwise.

>>7711008
thank you. this is by far the clearest and least autistic answer. what part of the system do enzymes get their energy from?

>>7710879
Free energy is energy available to do work. What's EoA friend?

>>7711049
energy of activation. it's a common acronym

>>7711051
It lowers the EoA by using it? Okay after reading, not specific at all. Sorry bud.

>>7711045
No problem. Like I said, it's really variable -- if you have a specific example you want to know about, post it. Enzymes typically gather free energy from one or two key steps in most metabolic processes that release enough energy to fuel several others, and more often than not, "enzymes" are really complexes of many sub-unit enzymes that work in sequence -- where the sum of their individual reaction energies acts as a driving force for all the individual ones that have energy barriers. ATP is a good example. Biochemical reactions of all kinds couple energetically unfavorable steps to the release of phosphate from ATP, so that they can occur "spontaneously." Conversely, creating ATP is a very energy-expensive process, and enzyme complexes in the electron transport chain use energy released in a series of reactions (where the free energy ultimately comes from consumed calories) to push hydrogen ions against a concentration gradient, storing them until there is enough potential energy that the "dam" breaks, and hydrogen flows across a protein channel (in the ATP synthase enzyme complex) that responds to the movement of hydrogen -- like a turbine in a hydroelectric dam -- to build ATP from ADP and phosphate.

Energy is a currency, and positive, net energy gain is the goal, but small-scale expenditures are made at certain steps to drive others that pay off later down the road, much like a business.

>>7710879
The enzyme provides a different path for the reaction to occur in, which requires less energy overall to complete.