Question | Answer |
True or False: Microbes utilize sugars just like we do to make ATP. | True |
What can be used by cells to make ATP? | Carbs, Lipids and Proteins |
Biological Reactions Catalyzed by enzymes | Metabolism |
What is anabolism? Does it require or release energy? | Building up; requires energy; endergonic |
What is catabolism? Does it require or release energy? | Breaking down; releases energy; exergonic |
All metabolic reactions are catalyzed by ________________. | Enzymes |
Give 5 aspects of anabolism that are different than catabolism. | Synthesis of larger molecules, products are larger molecules, photosynthesis, it is mediated by enzymes, and energy is required (endergonic). |
Give 5 aspects of catabolism that are different than anabolism. | Breakdown of larger molecules; products are small molecules, glycolysis and citric acid cycle, is mediated by enzymes, energy is released (exergonic) |
Enzymes are specific for what? | Substrate |
Where do substrates bind? | Substrate binds to the active site of the enzyme. |
Small amounts of enzyme = what? | Lots of product |
4 steps of the mechanism of enzyme action: | 1) Substrate binds to active site. 2) Formation of enzyme-substrate complex. 3) Catalysis of RX. 4) Products are released and the enzyme is reused. |
How do enzymes speed up reactions? | Decreasing activation energy |
How do enzymes decrease the activation energy? | Changing the conformation of substrate or positioning substrate in more optimal ways for RX to occur. |
What are 2 types of regulation of enzyme activity? | Competitive inhibition vs. non-competitive (allosteric) inhibition. |
How does competitive inhibition work? | Inhibitor resembles normal substrate. It blocks the active site and prevents substrate from binding. |
How does non-competitive (allosteric) inhibition work? | Inhibitor binds to allosteric site which alters shape and function of enzyme and changes the active site. Often mechanism for negative feedback in metabolic pathways. |
What is the universal form of cellular potential energy? | ATP |
In terms of energy utilization, are microbes thought of as open or closed systems? | Open Systems |
Microbes require what to do work? | Free Energy |
Microbes transfer potential energy stored in different molecules to what? | Potential Energy stored in ATP |
Give a brief overview (3 steps) of cellular respiration for the synthesis of ATP | 1) Partial Oxidation of glucose via glycolysis (anaerobic). 2) Fermentation in absence of molecular oxygen 3) Complete Oxidation of Glucose. |
5 Steps of Complete Oxidation of Glucose. | 1) Utilized by obligate aerobes. 2) Begins with glycolysis just like anaerobic cellular respiration. 3) Transition step (pyruvate to acetyl CoA) 4) Kreb's Cycle (Citric Acid Cycle). 5) Electron Transport chain and oxidative phosphorylation |
What are three uses/functions of glucose? | 1) Building block for energy storage and other polysaccharides. 2) Conversion to Ribose 5-phosphate for nucleic acid synthesis. 3) Glycolysis for energy utilization. |
What are the 2 phases of glycolysis? | Preparatory phase and Payoff (energy yielding) Phase |
Explain the preparatory phase of glycolysis. How many ATP is required? | Phosphorylation of glucose. Hydrolysis of 6 Carbon to 3 Carbon molecules and conversion to Glyceraldehyde 3-phosphate. 2 ATP required. |
Explain the Payoff phase in glycolysis. How many ATP are made? | Oxidative conversion of Glyceraldehyde- 3- phosphate to pyruvate. Redox reactions for the generation of NADH (2). Substrate level phosphorylation of ADP to ATP. 4 ATP made. |
Does glycolysis require oxygen? | No. It is the synthesis of 2-pyruvate from glucose. |
How many molecules of ATP are made from substrate level phosphorylation? | 2 ATP |
Where is NADH used? | Can be used by the electron transport chain to make ATP (If Aerobic) |
Is oxygen organic or inorganic? | Inorganic. Can serve as a reducing agent. |
In the absence of oxygen, what happens? | Fermentation |