Metabolism Flashcards
What is Anabolism
the metabolic process that transforms simple substances into complex molecules.
- Think (using the energy of ATP)
What is Catabolism
is where complex and large molecules are broken down into small ones.
- Think( synthesize ATP)
The central metabolic pathways are
- Glycolysis
- the TCA cycle
- the pentose phosphate pathway
How does ATP serve as a carrier of free energy
It has unstable phosphate bonds that are easily broken; cells have enzymes that help break those bonds to release the energy
How do enzymes catalyze chemical reactions?
enzymes catalyze by lowering the activtaion energy
Explain how precursor molecules are involved in catabolic as well as anabolic pathways.
There are two types of pathways either
- the precursor metabolites can be used to make subunits of macromolecules (anabolic) meaning they cans serve as carbon skeletons biosynthesis.
- Or the precursor metabolites can be oxidized to generate ATP (catabolic)
How do cells regulate enzyme activity?
Regulated enzymes are allosteric; when a molecule binds to the allosteric site, the enzyme changes shape, with alters its activity.
Why do the electrons carried by FADH2 result in less ATP production than those carried by NADH?
FADH2 has a higher affinity for electrons that NADH does, so the electrons it carries must be transferred to an even higher affinity molecule; it’s electrons are transferred to Complex II of the electron transport chain, which is “downstream” or “downstairs” of Complex I (the complex to which NADH transfers its electrons).
Name three food products produced with the aid of fermenting microorganisms.
Many options are possible here, including yogurt, cheese, pickles, kimchee, bread, sausage, chocolate, etc.
In photosynthesis, what is encompassed by the term “light reactions”?
Carbon fixation
Unlike the cyanobacteria, the anoxygenic photosynthetic bacteria do not produce O2. Why not?
They do not strip electrons from water.
Unlike the cyanobacteria, the anoxygenic photosynthetic bacteria do not produce O2. Why not?
They do not strip electrons from water.
What is the role of transamination in amino acid biosynthesis?
The amino group is removed from one amino acid and donated to another, generating a different amino acid.
Metabolism involves?
processes that transform energy; cells take energy of one form and convert it into another.
Metabolism is?
The sum total of chemical reactions of biosynthesis and energy-havesting
Metabolic Pathways can be..?
- linear
- branched
- cyclical
Adenosine triphosphate (ATP)
is the main energy currency of cell
What id ADP
Molecule that accepts an inorganic phosphate (Pi ) generating ATP.
NAD+/NADH is the abbrevietaion for what?
nicotinamide adenine dinucleotide
NADP+/NADPH is the abbreviation for what?
nicotinamide adenine dinucleotide phosphate
FAD/FADH2 is the abbreviation for what
flavin adenine dinucleotide
NAD+/NADH, NADP+/NADPH, and FAD/FADH2, are all examples of what?
Electron carriers
The 3 key metabolic pathways do what together?
They oxidize glucose to CO2
What are the 2 key sets of processes for Catabolism?
- Oxidizing glucose molecules to generate ATP, reducing power ( NADH, FADH^2, NADPH), and precursor metabolites.
- Transferring the electrons carried by NADH AND FADH^2
Glycolysis is the metabolic pathways that
That oxidizes glucose to pyruvate, generating ATP and reducing power.
The pentose phosphate metabolic pathway does what?
The metabolic pathway that starts the degradation of glucose, generating reducing power in form of NADPH and two precursor metabolites.
The Tricarboxylic acid (TCA) cycle is a part of the metabolic pathways doe what?
The cyclic metabolic pathway that incorporates acetyl-CoA, ultimately generating ATP (or GTP), CO2, and reducing power; also called the Krebs cycle and the citric acid cycle.
In fermentation cells?
Break down glucose through glycolysis only, thereby generating pyruvate
A cofactor is a
non-protein component required for the activity of some enzymes
Examples of cofactors are
Magnesium, zinc, copper, and other trace elements
Coenzymes are?
a subset of cofactors; they are loosely attached non-protein organic compounds that help some enzymes transfer certain molecules or electrons from one compound to another.
Most enzymes function best at?
low salt concentrations and at pH values slightly above 7
Competitive inhibition is when the
Inhibitor binds to the active site of the enzyme, blocking access of the substrate to that site. Competitive inhibitors such as sulfa drugs are used as antibacterial medications.
Non-competitive inhibition (by regulatory molecules) is when
Inhibitor changes the shape of the enzyme, so that the substrate can no longer bind the active site. This is a reversible action that cells use to control the activity of allosteric enzymes.
Non-competitive inhibition (by enzyme poisons) is when
Inhibitor permanently changes the shape of the enzyme, making the enzyme non-functional. Enzyme poisons such as mercury are used in certain antimicrobial compounds.
