Chapter 13 - Exam 3 Flashcards
Autotroph
use CO2 from the atmosphere as their sole source of carbon
Heterotroph
cannot use atmospheric CO2 and must obtain carbon from their outside environment
Metabolism
the chemical reactions in the organism
Metabolites
series of intermediates through which precursors are converted to products
Intermediary Metabolism
the combined activities of all the metabolic pathways that interconvert precursors, metabolites, and products of low molecular weight
Catabolism
the degradative phase of metabolism (releases energy)
Anabolism
the building phase of metabolism (requires energy)
What is ΔG?
expresses the amount of energy capable of doing work during a reaction at constant temperature and pressure
What is ΔH?
enthalpy (the heat content of the reacting system)
What is ΔS?
entropy (randomness or disorder in a system)
If ΔG is negative, then the reaction
proceeds foward
If ΔG is positive, then the reaction
proceeds in reverse
Understand how reactions are thermodynamically coupled
thermodynamically unfavorable reactions can be coupled to favorable reactions (often involves coupling to ATP hydrolysis)
Homolytic Cleavage
cleavage of a covalent bond where each atom leaves the bond as a radical, carrying one unpaired electron
Heterolytic Cleavage
cleavage of a covalent bond where one atom retains both bonding electrons (more common)