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Metabolism?
collection of controlled biochemical reactions that takes place within the cells of an organism.
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anabolism?
- all of the synthesis reactions in an organism taken together.
- building reaction
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catabolism?
- All of the decomposition reactions in an organism taken together.
- break down reactions
- release energy
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How do cells use nutrients and energy to build structure , grow, and reproduce through Metabolic processes?
- 1- every cell requires nutrients
- 2- metabolism requires energy from light or from catabolism of nutrients
- 3- energy is stored in the chemical bonds of adenosine triphosphate (ATP)
- 4- using enzymes, cells catabolize nutrient molecules to form elementary building blocks called precursor molecules.
- 5- using precursor molecules, energy from ATP, and enzymes, cells construct larger building blocks in anabolic reactions.
- 6- cells use enzymes and additional energy from ATP to anabolically link building blaock from macromolecules in polymerization ractions
- 7- cells assemble macromolecules into cellular structure, ribosomes, membranes, cell walls, etc
- 8- cells typically reproduce once they have doubled in size
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Contrast Oxidation and Reduction reactions:
- reduction- gain an electron
- oxidation- lose an electron
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What is the function of NAD+, NADP+, and FAD+?
- NAD+: vitamin derived electron carrier molecule
- NADP+: Vitamin derived electron carrier molecule
- FAD+:Vitamin derived electron carrier molecule
- reducing power
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What are the three types of ATP phosphorylation?
- substrate- level phosphorylation: transfer of phosphate to ADP from another phosphorylated substrate. (Glycolysis krebs cycle)
- Oxidative phophorylation: energy from redox reactions of respiration used to attach phosphate to ADP (ETC- electron transport chain)
- Photophosphorylation: light energy used to phosphorylate ADP
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What are the 6 basic categories of enzymes, and what type of reaction does each catalyze?
- hydrolases: catabolize molecules with the addition of water
- Isomerases: rearrange atoms within a molecule, nothing added or taken away
- Ligases or polymerases: join 2 molecules together- anabolic, need ATP.
- Lyases: split molecules w/o using water
- Oxidoreductases: remove or add electrons
- Transferases: Transfer functional groups
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Describe the components of a holoenzyme?
combination of an apoenzyme and its cofactors.
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apoenzyme?
Protein portion of protein enzymes that is inactive unless bound to one or more cofactors.
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cofactor?
inorganic ions or organic molecules that are essential for enzyme action.
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coenzyme?
organic cofactor
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Describe how Temperature, pH, and substrate concentration effect enzymes activity
- temperature- if too high or too low and enzyme is often no longer able to achieve a fit with its substrate
- pH- extremes denature enzymes. eahc enzyme has optimal pH
- substrate- increases enzymatic activity increases as more an more enzyme active sites bind more an more substrate molecules.
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Describe how competitive and noncompetitive inhibitors affect enzyme activity.
- Competitive- shaped such that they fit into an enzyme's active site and and thus prevent the normal substrate from binding.
- Noncompetitive- do not bind to the active site but instead prevent enzymatic activity by binding to an allosteric site located elsewhere on the enzyme
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How negative feedback (end-product inhibition) prevents the cell from wasting energy making a lot of unneeded product?
- end-product of a series of reactions inhibits an enzyme in an earlier part of the pathway.
- In E.coli the presence of the amino acid isoleucine allosterically inhibits the first enzyme in the anabolic pathway that produces isoleucine.
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