Examples of Gibbs free energy in the following topics:
-
- Free energy, called Gibbs free energy (G), is usable energy or energy that is available to do work.
- Free energy is called Gibbs free energy (G) after Josiah Willard Gibbs, the scientist who developed the measurement.
- Gibbs free energy specifically refers to the energy associated with a chemical reaction that is available after accounting for entropy.
- In other words, Gibbs free energy is usable energy or energy that is available to do work.
- Exergonic and endergonic reactions result in changes in Gibbs free energy.
-
- Activation energy is the energy required for a reaction to occur, and determines its rate.
- This small amount of energy input necessary for all chemical reactions to occur is called the activation energy (or free energy of activation) and is abbreviated EA.
- Since these are energy-storing bonds, they release energy when broken.
- The free energy released from the exergonic reaction is absorbed by the
endergonic reaction.
- Free energy diagrams illustrate the energy profiles for a given reaction.
-
- Since ATP hydrolysis releases energy, ATP synthesis must require an input of free energy.
- Exactly how much free energy (∆G) is released with the hydrolysis of ATP, and how is that free energy used to do cellular work?
- Unless quickly used to perform work, ATP spontaneously dissociates into ADP + Pi, and the free energy released during this process is lost as heat.
- The Na+/K+ pump gains the free energy and undergoes a conformational change, allowing it to release three Na+ to the outside of the cell.
- By donating free energy to the Na+/K+ pump, phosphorylation drives the endergonic reaction.
-
- A living cell cannot store significant amounts of free energy.
- Excess free energy would result in an increase of heat in the cell, which would lead to excessive thermal motion that could damage and then destroy the cell.
- ATP is often called the "energy currency" of the cell and can be used to fill any energy need of the cell.
- The hydrolysis of ATP produces ADP, together with an inorganic phosphate ion (Pi), and the release of free energy.
- The ADP molecule and a free phosphate ion are released into the medium and are available for recycling through cell metabolism.
-
- ATP is critical for muscle contractions because it breaks the myosin-actin cross-bridge, freeing the myosin for the next contraction.
- ATP first binds to myosin, moving it to a high-energy state.
- ADP and Pi remain attached; myosin is in its high energy configuration .
- As myosin expends the energy, it moves through the "power stroke," pulling the actin filament toward the M-line.
- At the end of the power stroke, the myosin is in a low-energy position.
-
- Mitochondria are organelles that are responsible for making adenosine triphosphate (ATP), the cell's main energy-carrying molecule.
- These features all support the hypothesis that mitochondria were once free-living prokaryotes.
- Mitochondria are often called the "powerhouses" or "energy factories" of a cell because they are responsible for making adenosine triphosphate (ATP), the cell's main energy-carrying molecule.
- ATP represents the short-term stored energy of the cell.
- Your muscle cells need a lot of energy to keep your body moving.
-
- Mitochondria are energy-producing organelles that are thought to have once been a type of free-living alpha-proteobacterium.
- Eukaryotic cells contain anywhere from one to several thousand mitochondria, depending on the cell's level of energy consumption.
- As the amount of oxygen increased in the atmosphere billions of years ago and as successful aerobic prokaryotes evolved, evidence suggests that an ancestral cell with some membrane compartmentalization engulfed a free-living aerobic prokaryote, specifically an alpha-proteobacterium, thereby giving the host cell the ability to use oxygen to release energy stored in nutrients.
- Alpha-proteobacteria are a large group of bacteria that includes species symbiotic with plants, disease organisms that can infect humans via ticks, and many free-living species that use light for energy.
- These features all support that mitochondria were once free-living prokaryotes.
-
- The addition of nucleotides requires energy; this energy is obtained from the nucleotides that have three phosphates attached to them, similar to ATP which has three phosphate groups attached.
- When the bond between the phosphates is broken, the energy released is used to form the phosphodiester bond between the incoming nucleotide and the growing chain.
- It also requires a free 3'-OH group to which it can add nucleotides by forming a phosphodiester bond between the 3'-OH end and the 5' phosphate of the next nucleotide.
- This means that it cannot add nucleotides if a free 3'-OH group is not available.
- A primer provides the free 3'-OH end to start replication.
-
- Mereschkowski was familiar with work by botanist Andreas Schimper, who had observed in 1883 that the division of chloroplasts in green plants closely resembled that of free-living cyanobacteria.
- Christian de Duve proposed that they may have been the first endosymbionts, allowing cells to withstand growing amounts of free molecular oxygen in the earth's atmosphere.
- Modern eukaryotic cells evolved from more primitive cells that engulfed bacteria with useful properties, such as energy production.
-
- A few protists live as colonies that behave in some ways as a group of free-living cells and in other ways as a multicellular organism.
- Protists that store energy by photosynthesis belong to a group of photoautotrophs and are characterized by the presence of chloroplasts.