CHP-6 Microbial Metabolism
In addition to yielding energy, catabolic pathways generate carbon intermediates that can be used in anabolic pathways for the biosynthesis of macromolecules. These carbon skeletons are called
precursor metabolites
The form of energy that results from the electrochemical gradient established by the electron transport chain is the
proton motive force
The three main types of electron carriers in a typical electron transport chain are
quinones, cytochromes, and flavorproteins
Certain intermediates of catabolic pathways, called precursor metabolites, are important because ______.
they serve as carbon skeletons from which subunits of macromolecules can be made
Until the optimal temperature is reached, raising the temperature has what effect on the speed of enzymatic reactions?
It increases their rate.
Which of the following are reasons an organism might use fermentation?
They lack an electron transport chain A suitable inorganic terminal electron acceptor is not available
The critical site of an enzyme to which a substrate binds by weak forces is called the
active site
Enzymes are biological __________ that are typically __________.
catalysts and protein
Proteins that function as biological catalysts are called
enzymes
Fats, the most common simple lipids, are broken down by lipases into their component
glycerol and fatty acids
Atoms that are more electronegative than others
have a higher affinity for electrons
Purines and pyrimidines are synthesized
in distinctively different manners
What are the two main forms of energy?
kinetic and potential
An atom that has a lower affinity for electrons than another is described as than the other.
less electronegative
The series of sequential chemical reactions in a cell that converts a starting compound to an end product is called a
metabolic pathway
When a cell processes glucose or other organic molecules through its central metabolic pathways, it does so to generate what three critical things?
ATP, reducing power, precursor metabolites
Non-competitive inhibition by regulatory molecules
Allosteric regulators
In addition to glucose, which of the following organic compounds can serve as energy sources for microbes?
Disaccharides, polysaccharides, lipids, fatty acids, monosaccharides, proteins
Which of the following correctly describe cytochromes found in an electron transport chain?
Several different cytochromes exist.
Competitive inhibition
Sulfa drugs
The sum total of all chemical reactions in a cell is called
metabolism