Term
| When a virus inserts itself into the genome of a cell and remains dormant rather than progressing to lysis, this is the (lysogenic/lytic) phase. |
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Definition
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Term
| What is a viral envelope? |
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Definition
| This is a lipid bilayer surrounding the capsid of some viruses. It arises from the plasma membrane of the cell from which the virus buds, and frequently contains glycopeptides that take part in host-cell recognition. |
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Term
| Give a detailed description of the life cycle of a retrovirus? |
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Definition
| A retrovirus infects a cell by binding to receptors on the membrane and being drawn into close proximity, so that the envelope fuses with the cell membrane. The capsid enters the cell and the genomic RNA is unpacked. Reverse transcriptase makes a DNA copy that then inserts into the host genome. From there, it is transcribed both to reproduce the viral genome and to serve as an mRNA for the production of the viral proteins. These self-assemble, before the mature virus buds off from the infected cell. |
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Term
| What biomolecule represents the major reservoir for energy in the cell? |
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Definition
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Term
| A reaction that requires the input of energy is termed (endergonic,exergonic). |
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Definition
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Term
| What does the First Law of Thermodynamics state? |
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Definition
| Energy is neither created nor destroyed |
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Term
| Describe the effect of an enzyme on a reaction. How will it affect the speed of the reaction? the energy of activation? The change in free energy? |
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Definition
| An enzyme is a biochemical catalyst that speeds up the rate of a reaction by reducing the energy of activation. Since the substrates and products remain the same, there is no difference in the change of free energy. |
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Term
| What does Redox refer to? |
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Definition
| It refers to reduction and oxidation. (The terms are combined since for every redox reaction, both are happening – one compound is reduced as the other is oxidized. |
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Term
| An organism that can harvest energy from light but not fix carbon is called a (chemoautotroph, chemoheterotroph,photoautotroph,photoheterotroph). |
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Definition
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Term
| In a redox reaction, what does an oxidating agent do to a substrate, with respect to its electrons? |
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Definition
| The oxidating agent oxidizes the substrate, taking electrons from it. |
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Term
| Describe the mechanism for non-competitive inhibition. How does it respond to the presence of additional substrate, and why? |
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Definition
| In non-competitive inhibition, the inhibitor binds to the enzyme at a different site than the active site. It inhibits the reaction by changing the shape of the enzyme, so that it can no longer bind the substrate. This will be the case no matter how much substrate is present, so increasing substrate will change nothing. |
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Term
| Give a characteristic of mitochondria and chloroplasts that supports the hypothesis that they derive from ancient symbiosis. |
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Definition
| Double membrane, they have their own circular DNA genome, make their own ribosomes, carry out their own transcription and translation, and divide by binary fission. |
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Term
| What biomolecule is the located at the reaction center core of the photosystems (carotinoids, chlorophyll A,chlorophyll B) |
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Definition
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Term
| What is the electron donor in the light reactions of photosynthesis. What is the ultimate acceptor? |
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Definition
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Term
| Explain how the function of the electron transport chain gives rise to ATP. |
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Definition
| The electron transport chain passes excited electrons to a lower energy state through progressive steps that use portions of the energy to pass protons across the membrane from the stroma to the thylakoid space. This creates a proton gradient that then serves as the driving force for ATP synthase, allowing these electrons to flow down the gradient, driving its rotor and creating mechanical energy that causes the catalytic domain to produce ATP. |
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Term
| What reaction is performed by the enzyme rubisco? |
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Definition
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Term
Which of the following are products of the Calvin cycle? [select all that apply]
(CO2, Rubisco, NADPH, G3P, ADP, proton gradient) |
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Definition
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Term
| What enzyme carries out carbon fixation? |
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Definition
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Term
| Explain how C4 plants differ from C3 plants in terms of their carbon fixation. What are the implications for arid environments? |
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Definition
| C4 plants fix Carbon dioxide producing a 4-carbon compound. These compounds are then passed to a different cell where the CO2 is stripped off and passed to rubisco. This temporally separates carbon fixation from the Calvin cycle, contrasting it with C3 plants where the carbon dioxide is directly fixed from the environment by rubisco. As a result, in arid environments can take on CO2 at a time of low evaporation, and only later carry out the Calvin cycle as the energy is being produced at a time when evaporation would be a concern. |
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Term
| Name a process seen in photosynthesis that is also seen in cellular respiration. |
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Definition
| ATP-synthase using a proton gradient to make ATP |
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Term
| An enzyme that simply rearranges the atoms within a molecule is a (dehydrogenase,isomerase, kinase). |
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Definition
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Term
| When the product of glycolysis is imported into the mitochondria, to produce acetyl-CoA, what is this called? |
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Definition
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Term
| Describe the processes of energy investment and energy payoff in glycolysis. |
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Definition
| In the energy investment phase, a glucose is rearranged and activated by the addition of two phosphates from ATP, then it is split in two, resulting in a pair of G3P molecules. Then in the payoff portion of glycolysis, these G3P molecules are passed through a sequence of reactions that oxidize them, creating two NADH, and likewise release energy to form four ATP. The final product is a pair of pyruvates. |
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Term
| What is the fate of the NADH and FADH2 produced during cellular respiration? |
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Definition
| They are oxidized, passing their electrons down the electron transport chain of oxidative phosphorylation |
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