= the synthesis of a polypeptide (under the direction ..

Metabolism may be defined as the total of all the chemical reactions that occur in organisms. Green plants can synthesize all the thousands of compounds they contain from carbon dioxide, water, and inorganic nutrients. The discussion of the complicated topic of metabolism is somewhat simplified by separation of the subject into two areas—catabolic and anabolic metabolism. Catabolic metabolism is degradative and is generally exergonic. ATP is a product of catabolic metabolism. In contrast, anabolic metabolism is synthetic and requires ATP. Fortunately, there are relatively few major pathways of energy metabolism.

Polypeptide synthesis proceeds until ER signal ..

Hypothesize if DNA replication and protein synthesis are endergonic or exergonic

Exergonic and endergonic reactions differ in that

As Mitchell predicted (1-3), the mitochondrial, bacterial, and chloroplast membranes that couple ATP synthesis to electron transport are poorly permeable to protons, except when proton-linked processes, such as ATP formation, occur at high rates. Proton transport was shown to be linked to electron transportin mitochondria (4), chloroplasts (5), and bacteria (6). The measurements of the magnitudes oficross these membranes turned out to be difficult, but in most instances, values approaching 20 kJ mol-1 (Dp ~ 200 mV) have been measured during steady state, rapid electron transport. As predicted by Mitchell, lipophilic weak acids (eg, 2,4-dinitrophenol) could collapse the A^H-by shuttling protons across the membrane. ATP synthesis is also inhibited by these reagents, which are termed "uncouplers" because they uncouple electron flow and ATP synthesis.

through dehydration synthesis, and become a polypeptide, ..

You have frequently heard ATP referred to as the "universal energycurrency" of the cell, and this is true for all organisms. Why ATP ended upbeing such a pivotal coenzyme, and not GTP, UTP, etc., is probably just a matterof chance. The free energy of biological oxidation reactions can be stored inthe bonds of ATP (chemical energy). It's relatively easy to hydrolyzepyrophosphate linkages in ATP, with the result that a considerable amount offree energy is released (Go' = -30.5kJ/mol for ATP hydrolysis to ADP and Pi ).If this were released intothe cell as heat, it would serve no useful purpose as far as making anendergonic chemical reaction proceed, since there's no way for the cell totransduce heat energy into work. But, if two reactions are "coupled"such that the product of an endergonic reaction is the reactant of an exergonicone (and the magnitude of the free energy change of the exergonic one is greaterthan that of the endergonic) then the exergonic reaction pulls the endergonicone through an intermediate. In other words, for chemical energy to be socoupled, there must be an intermediate common to both reactions in the set.

Is Protein Synthesis endergonic or exergonic

In both cases two electrons are transferred to oxygen, so that the n in Eq. (1) is equal to 2. Under standard conditions, the oxidation of 1 mol of NADH by oxygen liberates close to 53 kcal, whereas the AG0 for that of FADH2 is —38 kcal/mol. These two strongly exergonic reactions provide the energy for the endergonic synthesis of ATP.

Protein Synthesis & The Genetic Code OBSR ..

IMP is also subject to regulation at points after its production. AMP and GMPeach competitively inhibit their own production. Also, each AMP synthesizedrequires one GTP and each GMP synthesized requires one ATP, in a reciprocalfashion as mentioned above. As about equal amounts of AMP and GMP are needed innucleic acid synthesis, this reciprocity provides for that. The rate ofproduction of AMP increases with increasing concentrations of GTP, and that ofGMP with increasing concentrations of ATP.

The energetics of organic synthesis inside and outside the cell

AB - Thermodynamic modelling of organic synthesis has largely been focused on deep-sea hydrothermal systems. When seawater mixes with hydrothermal fluids, redox gradients are established that serve as potential energy sources for the formation of organic compounds and biomolecules from inorganic starting materials. This energetic drive, which varies substantially depending on the type of host rock, is present and available both for abiotic (outside the cell) and biotic (inside the cell) processes. Here, we review and interpret a library of theoretical studies that target organic synthesis energetics. The biogeochemical scenarios evaluated include those in present-day hydrothermal systems and in putative early Earth environments. It is consistently and repeatedly shown in these studies that the formation of relatively simple organic compounds and biomolecules can be energy-yielding (exergonic) at conditions that occur in hydrothermal systems. Expanding on our ability to calculate biomass synthesis energetics, we also present here a new approach for estimating the energetics of polymerization reactions, specifically those associated with polypeptide formation from the requisite amino acids.