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System:
Constituent reactants and products, the solvent that contains them, and the immediate atmosphere
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Isolated system:
Does not exchange energy or matter with its surroundings.
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Closed system:
Exchanges energy but not matter with the surroundings
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Open system:
Exchanges energy and matter with the surroundings.
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A living organism is what type of system
A living organism is an open system, it exchanges both matter and energy with its surroundings
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What are the two ways Organisms derive energy from their surroundings?
- Chemotrophs take up chemical fuels (such as glucose) from the environment and extract energy by oxidizing them -Phototrophs they absorb energy from sunlight
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What is the First Law of Thermodynamics
describes the principle of conservation of energy
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What are energy transducers
Energy transducers transform energy from one form to another
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Cells are consummate transducers of energy, what does this mean
They capable of interconverting chemical, electromagnetic,mechanical, and osmotic energy with great efficiency)
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When complex molecules are broken down what is the effect on entropy
entropy increases
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When complex molecules are biult from simple molecules what is the effect on entropy
entropy decreases
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What is the chemical formula for photosynthesis
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Non-photosynthetic organisms obtain energy by oxidizing the products of photosynthesis through what formula
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second law of thermodynamics,
the tendency in nature is toward ever greater disorder in the universe: the total entropy of the universe is continually increasing
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a molecule high in information has what level of entropy?
low because information is negative entropy
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According to Gibbs free energy of any closed system can be defined in terms these three quantities
- -Enthalpy (H): reflects the number and kinds of bonds
- -Entropy (S): The degree of randomness
- -Temperature: In degrees Kelvin
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What are the formulas for Free energy change()
is used to measure the energy change as the system moves from its initial state to equilibrium
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What is the definition of Free energy (G)
Free Energy: G=H -TS
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What is it called when is Greater than Zero for a chemical reaction
Endergonic: Non-spontaneous process, needs input of free energy to proceed
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What is it called when is Less than Zero for a chemical reaction
Exergonic; Spontaneous process, releases free energy which can be used to do work; proceeds until equilibrium is reached
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What is it called when is Zero for a chemical reaction
System is at equilibrium – the rate of the forward reaction equals the rate of the reverse reaction. There is no change in free energy in the system
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What doe it mean when is Positive
= Endothermic Reaction, Enthalpy increases and Heat is absorbed
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What doe it mean when is Negative
= Exothermic. Enthalpy decreases and Heat is Released
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How does the cell carry out endergonic reactions (reactions that require energy)?
cells couple them to other reactions that liberate free energy (exergonic reactions), usually ATP by breakage of a phosphoanhydride, so that the overall process is exergonic
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When do chemical reactions stop?
When equilibrium is reached( =0)
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When is a Chemical reaction at equilibrium?
- -when the rate of product formation equals the rate of reactant formation so there is no net change in the concentration of reactants and products
- - When = 0
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What is the equilibrium constant ()?
- -the higher the the greater the likelyhood of a reaction to proceed to completion (no equilibrium only products made)
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What is standard free energy change?
a constant that is characteristic of each specific reaction and a term that expresses the initial concentrations of reactants and products.
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What are the three ways enzymes catalyze reactions?
- -by providing a surfacet that complements the transition state in stereochemistry polarity, and charge.
- -The binding of enzyme to the transition state is exergonic, and the energy released by this binding reduces the activation energy for the reaction and greatly increases the reaction rate.
- -Enzymes can also catalyze reactions by binding two or more reactants and positioning them close to each other with stereospecific orientations that favor the reaction.
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What is activation energy?
the difference in energy between the reactant in its ground state and in its transition state
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What is a transition state?
the configuration of the reactants corresponding to the time of highest energy in the reaction.(transition state has a higher free energy than either product or reactant)
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What is a Reaction Pathway?
a sequence of consecutive reactions where the product of one reaction becomes the reactant in the next
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