Exam 3: Energy, Catalysis, and Biosynthesis

The reduction of a molecule can sometimes result in the acquisition of a proton, a reaction referred to as

The best way to know if an organic molecule has been reduced is to see if there was an increase in the number of __________ bonds.

Chemical reactions carried out by living systems depend on the ability of some organisms to capture and use atoms from nonliving sources in the environment.The specific subset of these reactions that break down nutrients in food can be described as

All of the biological molecules listed below contain high-energy phosphate bonds.Which one is the key driver of most phosphorylation reactions and the transfer of metabolic energy?

Protein E can bind to two different proteins, S and I.The binding reactions are described by the following equations and values: E + S → ES K_eq for ES = 10 E + I → EI K_eq for EI = 2 Given the equilibrium constant values, which one of the following statements is TRUE?

When elemental sodium is added to water, the sodium atoms ionize spontaneously.Uncharged Na becomes Na⁺.This means that the Na atoms have been

For each of the following sentences, fill in the blanks with the best word or phrase selected from the list below.Not all words or phrases will be used; each word or phrase should be used only once. activation free selectively chemical bond kinetic slowly completely rapidly unfavorable favorable By definition, catalysts allow a reaction to occur more __________. Chemical reactions occur only when there is a loss of __________ energy.Enzymes act more __________ than other catalysts.A catalyst decreases the __________ energy of a reaction.

In the cytoplasm, materials are organized, separated, and sorted by membranes.Cells exploit the selective permeability of these membranes to partition populations of molecules and generate chemical energy for the cell.Use the principles of the first and second laws of thermodynamics to explain how membranes can be used to produce chemical energy.

Seed oils are often dehydrogenated and added back into processed foods.The new fatty acids have an increased number of carbon-carbon double bonds.The dehydrogenation reaction could also be described as a/an __________ reaction.

The study of enzyme kinetics is usually performed with purified components and requires the characterization of several aspects of the reaction, including the rate of association with the substrate, the rate of catalysis, and

The synthesis of glutamine from glutamic acid requires the production of an activated intermediate followed by a condensation step that completes the process.Both amino acids are shown in Figure 3-46. Figure 3-46 Which molecule is added to glutamic acid in the activation step?

For the reaction Y→X at standard conditions with [Y] = 1 M and [X] = 1 M, ΔG is initially a large negative number.As the reaction proceeds, [Y] decreases and [X] increases until the system reaches equilibrium.How do the values of ΔG and ΔG° change as the reaction equilibrates?

NADH and NADPH are activated carrier molecules that function in completely different metabolic reactions.Both carry two additional __________ and one additional __________.This combination can also be referred to as a hydride ion.

When the polymer X-X-X ...is broken down into monomers, it is "phosphorylyzed" rather than hydrolyzed, in the following repeated reaction:                               X-X-X ...+ P ? X-P + X-X ...(reaction 1) Given the ?G° values of the reactions listed in Table 3-27, what is the expected ratio of X-phosphate (X-P) to free phosphate (P) at equilibrium for reaction 1?                               X-X-X ...+ H₂O ? X + X-X ...?G° = ?4.5 kcal/mole                               X + ATP ? X-P + ADP ?G° = ?2.8 kcal/mole                               ATP + H₂O ? ADP + P ?G° = ?7.3 kcal/mole Table 3-27

Assume that the average human adult requires 2000 kilocalories per day to sustain all normal processes and maintain a constant weight.If manufactured solar panels could somehow provide power directly to the human body, what size solar panel would be required (in cm²)? Assume there are 10 hours of sunlight per day, and that the usable energy output for a typical solar panel is 850 kJ/ft² per hour. Note: 1 kcal = 4.184 kJ 1 ft² = 929.03 cm²

Figure 3-72 illustrates the amount of energy per molecule for a population in a contained, controlled environment.Most molecules will have the average energy of the population, shown in region 1.The number of molecules in the population with enough energy to be converted to product is shown in region 2.The number of molecules with enough energy to react in the presence of enzyme is shown in region 3.Use this information to explain how enzymes catalyze reactions. Figure 3-72

The graph in Figure 3-34 illustrates the relationship between reaction rates and substrate concentration for an enzyme-catalyzed reaction.What does the K_m value indicate with respect to enzyme-substrate interactions? Figure 3-34