What is energy?
the capacity to do work
Energy currency is
Adenosine 5'-triphosphate (ATP)
3 types of cellular work
chemical, mechanical, and transport work
Ultimate source of all biological energy is _______________ ______________ through __________________________
Visible, Light, Photosynthesis
Complex molecules made by photosynthesis serve as
carbon sources for chemoheterotrophs
Major energy currency in living cell is ATP (True/False)
True
first law of thermodynamics
Energy cannot be created or destroyed. Total energy in the universe remains constant
Second Law of Thermodynamics
Physical and chemical processes proceed in such a way that the disorder of the universe increases to the maximum possible level.
What is the degree of disorder?
Entropy
How is free energy change calculated?
G = H - T * S
What does the G stand for in the equation G = H - T * S?
the change in free energy
What does the H stand for in the equation G = H - T * S?
the change in enthalpy
What does the T stand for in the equation G = H - T * S?
the temperature in degrees Kelvin (*C +273)
What does the S stand for in the equation G = H - T * S?
the change in entropy
Free energy change (G) is the amount of energy in a system that is unavailable to do work (True/False)
False (*available to do work)
What is standard energy?
the change in free energy under standard conditions of concentration ,pH, pressure, and temperature.
Negative G* indicates
exergonic reaction
Positive G* indicates
endergonic reaction
______________ ____________ removed by hydrolysis yields large -G*
Terminal Phosphate
the addition of a phosphate group to a chemical compound
Phosphorylation
generation of ATP by the transfer of a high energy phosphate to ADP
Substrate-level phosphorylation-
The synthesis of ATP coupled with electron transport
Oxidative phosphorylation-
The production of ATP in a series of redox reactions
Photophosphorylation
ATP has high phosphate group transfer potential (True/False)
True
_____________________ breakdown of ATP is frequently coupled with ______________________ synthesis reactions
Exergonic, Endergonic
Metabolic-energy-trapping processes are used to
catalyze the formation of ATP from ADP + Pi
The four inhibitors of enzymes
Competitive, Non-competitive, Allosteric, Feedback inhibition
Competitive
fills the active site and prevents the interaction of the substrate
Non-competitive
does not compete with the active site of the substrate
Allosteric
when the inhibitor binds to another site other than the substrate binding site
Feedback Inhibition
regulation by the end product of the reaction
factors influencing enzymatic activity (
temperature, pH, substrate concentration
Oxidation-reduction (redox)
a couple reaction in which one substance is oxidized and one is reduced
Electron Carriers
transfer electrons from a reductant to an acceptor with a greater, more positive reduction potential
A few electron carriers
NAD+, NADP+, Flavoproteins, Coenzymes, Cytochromes
Glycolysis
oxidation of glucose into pyruvic acid (net gain of 2 ATP and 2 NADH) Kreb cycle-oxidation of acetyl to CO2 to gain 2 ATP,6 NADH, 2 FADH2
Electron transport system
ADH and FADH2are oxidized; oxidation-reduction reactions results in the generation of ATP.
ATP total in Carbohydrate catabolism
36-38
Anaerobic respiration
fermentation (without the use of oxygen)
Aerobic respiration
requires oxygen (final acceptor)
uses a series of electron carriers to transport electrons from NADH and FADH2,in a series of redox reactions, to a terminal electron acceptor (O2)
Mitochondrial electron transport chain
extensively branched with several terminal oxidases, may be composed of different electron carriers, may be shorter than the mitochondrial electron transport chains; located in the plasma membrane
Bacterial electron transport chain
Chemiosmotive hypothesis of oxidative phosphorylation postulates that
a proton gradient is formed with the above energy
NADH is not usually oxidized by the ________________ _____________ ____________ in the absence of molecular oxygen
electron transport chain
NADH must be ______________ to replenish the supply of NAD+ for use in the catalysis of glucose
oxidized
reactions that regenerate NAD+ from NADH in the absence of O2
Fermentations
Types of Fermentations
Alcoholic(ethanol and CO2) Lactic acid(Lactic acid~ Homolactic/Heterolactic Fermenters) Formic acid (either mixed acids orbutanediol)
Common energy sources
Triglycerides
What is catalyzed by the beta-oxidation pathway to acetyl-CoA, NADH, and FADH2?
Fatty Acids
What may enter the Citric Acid Cycle?
Acetyl-CoA
What may enter the electron transport chain
NADH and FADH2
Amino acids are degraded by proteases to Proteins (True/False)
False (Proteins are degraded by proteases to amino acids)
The NH2 group is removed by
deamination or transamination
The resulting organic acids are converted to
pyruvate, acetyl-CoA, or a Krebs Cycle intermediate
Amino acid synthesis requires the attachment of an
amino group to a carbon skeleton
Carbon skeletons are ________________ from acetyl-CoA, TCA cycle intermediates, glycolytic intermediates, and pentose phosphate pathway intermediates
Synthesized
Replenish Citric Acid cycle intermediatesso that biosynthesis can occur. Are not limited to autotrophic organisms
Anaplerotic Reactions
use CO2 only to maintain metabolic balance and to replace Krebs cycle intermediates
Heterotrophic organisms
Purines, pyrimidines, and nucleotides important because they are used in
ATP, several cofactor, RNA, and DNA synthesis
Purine biosynthesis is very complex (True/False)
True
uses aspartic acid and carbamoyl phosphate to form the initial pyrimidine product
Pyrimidine biosynthesis
Pyrimidines and purines are joined with
pentose sugars to form nucleoside
Phosphorylation of the nucleoside forms the nucleotide (True/False)
True
very vulnerable to disruption by antimicrobial agents, including antibiotics such as beta-lactam ring containing antibiotics ; Complex 8-stage process
Peptidoglycan synthesis
What is able to weaken the cell wall and can cause lysis
Inhibition of any step in the process of peptidoglycan synthesis