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3. List and describe the typical components of an enzyme (apoenzyme, cofactor, coenzyme, and holoenzyme).

-Enzymes are proteins, produced by living cells, that catalyze chemical reactions by lowering the activation energy. -Most enzymes are holoenzymes, consisting of a protein portion (apoenzyme) and a nonprotein portion (cofactor). -The cofactor can by a metal ion (iron, copper, magnesium, manganese, zinc calcium, or cobalt.) Or a complex organic molecule known as a coenzyme. (NAD+, NADP+, FMN, FAD, or coenzyme A).

14. Characterize the reactions and products of ethanolic and lactic acid fermentation.

-Ethanolic fermentation: alcohol fermentation pyruvic acid is reduced by NADH to produce ethanol. -Lactic fermentation: pyruvic acid is reduced by NADH to lactic acid. -Fermentation releases energy from sugars or other organic molecules by oxidation. -O2 is NOT required in fermentation. -2 ATP molecules are produces by substrate levels phosphorylation. -Electrons removed fro the substrate reduce NAD+. -The final electron acceptor is an organic molecule. -Heterolactic fermenters can use the pentose phosphate pathway to produce lactic acid and ethanol.

6. Distinguish between competitive and noncompetitive inhibition of enzyme activity.

-Inhibitors: Competitive inhibitors complete w/the normal substrate for the active site of the enzyme. -Noncompetitive inhibitors act on other parts of the apoenzyme or on the cofactor and decreases the enzyme's ability to combine w/the normal substrate.

15. Describe the general process by which lipids and proteins undergo catabolism.

-Lipases hydrolyze lipids into glycerol and fatty acids. -Fatty acids and other hydrocarbons are catabolized by beta oxidation. -Catabolic products can be further broken down in glycolysis and the Kreb's cycle. -Before amino acids can be catabolized, they must be converted to various substances that enter the Kreb's cycle. -Transamination, decarboxylation, dehydrogenation reaction convert the amino acids to be catabolized.

11. Identify the functions of the oxidative pentose phosphate and Entner-Doudoroff pathways.

-Pentose phosphate pathway: is used to metabolize fove-carbon sugars; one ATP and 12 NADPH molecules are produced from one glucose molecule. -Enter-Dondoroff: pathway yields one ATP and two NADPH molecules from one glucose molecule.

12. Describe the chemiosmotic theory of ATP production.

-Protons being pumped across the membrane generate a proton motive force as electrons move through a series of acceptors or carriers. -Energy produced from movement of the protons back across the membrane is used by ATP synthase to make ATP from ADP and Pi-. -In eukaryotes, electron carriers are located in the inner mitochondrial membrane; in prokaryotes electron carriers are in the plasma membrane.

5. List and describe the factors that influence enzyme activity (temperature, pH, substrate concentration, presence or absence of inhibitors).

-Temperature: at high temperatures, enzymes undergo denaturation and lose their catalytic properties: at low temperatures the reaction rate decreases. -pH: at which enzymatic activity is maximal is known as the optimum pH. -Concentration: Enzymatic activity increases as substrate concentration increases until the enzymes are saturated.

2. Identify the role of ATP as an intermediate between catabolism and anabolism.

-The energy of catabolic reactions is stored in ATP. -The energy for chimical reactions is stored in ATP.

4. Describe the mechanism of enzyme action.

-When an enzyme and substrate combine, the substrate is transformed and the enzymes is recovered. -Enzymes are characterized by specificity which is a function of their active site.

1. Define metabolism and describe the fundamental differences between anabolism and catabolism.

1. Metabolism- Refers to the sum of all chemical reactions within a living organism. Because chemical reactions either release or require energy, metabolism can be viewed as an energy balancing act. 2. Catabolism- refers to chemical reactions that result in the breakdown of more complex organic molecules into simpler substances. Catabolic reactions usually release energy. 3. Anabolism- Refers to chemical reactions in which simpler substances are combined to form more complex molecules. Anabolic reactions usually require energy.

9. Explain the overall function of metabolic pathways.

A series of enzymatically catalyzed chemical reactions called metabolic pathways store energy in and release energy from organic molecules.

13. Compare and contrast aerobic and anaerobic respiration.

Aerobic respiration: In aerobic prokaryotes, 38 ATP molecules can be produced from complete oxidation of a glucose molecule in glycolysis, the Kreb's cycle, and th electron transport chain. -In eukaryotes, 36 ATP molecules are produced from complete oxidation of a glucose molecule. Anaerobic respiration: the final electron acceptors in anaerobic respiration include NO3-, SO4^2-, and CO3^2-. -The total ATP yield is less than i aerobic respiration because only part of the Kreb's cycle operates under anaerobic conditions.

16. Distinguish between the following nutritional patterns among organisms: chemotroph, phototroph, heterotroph, autotroph, chemoheterotroph, chemoautotroph, photoheterotroph, and photoautotroph.

Carbon Source: -heterotroph: (feeds on others) require an organic carbon source. Can be further broken down into the following: **photoheterotropth (uses light for Energy and they fix organic molecules (Carbon). use light as an energy source and organic compound for their carbon source and electron donor. ** chemoheterotroph - use organic molecules fro both energy and for carbon fixation .: use complex organic molecules as their carbon and energy sources. **Chemoautotroph - use inorganic molecules as their energy source. use inorganic compounds as their energy source and carbon dioxide as their carbon source. -Autotroph: (self feeders) use carbon dioxide. *** oxygenic autotroph... photoautotropth.... anoxygenic autotroph. **photoautotroph - light + energy, CO2 as Carbon. obtain energy by photophosphorylation and fix carbon from CO2 via the Calvin-Benson cycle to synthesize organic compounds. Energy Source: -Chemotroph: depend on oxidation reduction reactions of inorganic or organic compounds for energy. -Phototroph: use light as their primary energy source.

8. List and provide examples of the three types of phosphorylation reactions that generate ATP.

Energy released during certain metabolic reactions can be trapped to form ATP from ADP and phosphate. Addition of a (p) to a molecule is called phosphorylation. 1. During substrate-level phosphorylation, a high energy from an intermediate in catabolism is added to ADP. 2. During oxidative phosphorylation energy is released as electrons are passed to a series of electron acceptors (an electron transport chain) and finally to O2 or another inorganic compound. 3. During photophosphorylation energy from light is trapped by chlorophyll, and electrons are passed through a series of electron acceptors. The electron transfer releases energy used for the synthesis of ATP.

10. Describe the functions of glycolysis, the intermediate step, and the Kreb's cycle, including explaining the relationship between the input and the output of the pathways and the expected yield of ATP, NADH, and FADH2

Glycolysis- The most common pathway for oxidation of glucose is glycolysis. Pyruvic acid is the end product. -Two ATP and two NADH molecules are produced from one glucose molecule. -Kreb's cycle: Decarboxylation of pyruvic acid produces one CO2 molecule and one acetyl group. -2 carbon acetyl groups are oxidized in the Kreb's cycle Electrons are picked up by NAD+ and FAD for the electron transport chain. -From on molecule of glucose, oxidation produces six molecules of NADH, 2 molecules of FADH2, and 2 molecules of ATP. -Decarboxylation produces six molecule of CO2.

7. Define oxidation-reduction.

Is the removal of one or more electrons from a substrate. Protons (H+) are often removed w/electrons. -Each time a substrate is oxidized, another is simultaneously reduced. -Reduction of a substrate refers to its gain of one or more electrons. -NAD+ is the oxidzed form; NADH is the reduced form. -Glucose is a reduced molecule ; energy is released during a cell's oxidation of glucose.