Chapter 3 Flashcards
second law of thermodynamics
the universe tends toward disorder
entropy
thermodynamic quantity that measures the degree of disorder in a system
___ is energy in its most disordered form
heat
first law of thermodynamics
energy cannot be created or destroyed
first stage of photosynthesis
energy from sunlight is captured and transiently stored as chemical-bond energy in activated carriers
second stage of photosynthesis
activated carriers are used to help drive a carbon-fixation process, in which sugars are manufactured from CO2
oxidation
removal of electrons from an atom
LEO
reduction
addition of electrons to an atom
GER
oxidized
donate a pair of electrons
reduced
accept a pair of electrons
which of these if produced by cell respiration, and what state of carbon does this by-product represent?
-CO2;completely oxidized carbon
-CO2;reduced version of carbon
-C6H12O6;completely oxidized carbon
-C6H12O6;reduced version of carbon
CO2; completely oxidized carbon
Which statement is true?
-A cell generates order by decreasing the entropy of its surroundings
-Cells obey the first law of thermodynamics but are exempt from the second law
-A cell takes in heat from the environment to power its biosynthetic reactions, thereby obeying the second law of thermodynamics
-The heat released by an animal cell comes from the chemical bond energy present in the food molecules it metabolizes
the heat released by an animal cell comes from the chemical bond energy present in the food molecules it metabolizes
enzyme
a protein that catalyzes a specific chemical reaction by lowering the activation energy
free energy (G)
energy that can be harnessed to do work or drive chemical reactions
catalyst
substance that accelerates a chemical reaction by lowering its activation energy
enzymes molecules are _____ after participating in a reaction
unchanged