Which of the following statements about enzyme mechanism reaction steps are true (select all that apply)?...

Which of the following statements about enzyme mechanism reaction steps are true (select all that apply)?

		On a reaction coordinate diagram, a reversible step is indicated by reactant and product at similar energy
		Irreversible steps are important in enzyme mechanisms to help ensure enzymes catalyze reactions in the desired direction
		Substrate binding is usually an irreversible step
		Irreversible steps of a reaction mechanism are always very slow
		To determine if a step is reversible or irreversible, it is necessary to know the activation energy of the step

Expert Solution

Ans. Option A. False. The energy of product is generally lower than that of the reactant.

Option B. True. The irreversible reaction ensures the unidirectional conversion of reactant into product, but never in backward direction.

For example, phosphorylation of glycose into G-6-P in first step of glycolysis ensures that this step and other reactions of the pathways proceed in specified desired direction.

Option C. False. Substrate binding is always reversible.

Option D. False. The rate of a reaction depending on relative concertation of products, reactants, temperature, etc. Irreversibility of a reaction is NOT a parameter for its rate. For example, hydrolysis of phosphoenol pyruvate into pyruvate and ATP is irreversible and fast.

Option F. False. To know if a reaction is reversible or irreversible, the standard free energy change (dG^0’) and experimental free energy change (dG) are required.

If, dG < dG^0’ - the reaction is irreversible.

Also, for simplicity, a reaction with –ve value of dG^0’ is usually considered irreversible.

queen_honey_blossom answered 2 years ago

Which of the following statements are true about the accounting transactions? Select all that apply Transactions...

Which of the following statements are true about the accounting transactions? Select all that apply Transactions occur when a source document (e.g., a billing) arrives, a time-based obligation (e.g., payroll payment deadline) occurs, or when closing accounts to prepare financial reports. A transaction will always debit one account and credit another account. When journalizing a transaction, the following equation must be maintained: Assets + Net Worth = Revenues + Liabilities + Expenses. None of the above.

Which of the following are true statements about ketones? Select all that apply: Acetone can be...

Which of the following are true statements about ketones? Select all that apply: Acetone can be used as a solvent for lacquer (including fingernail polish). They each contain a functional group in the middle of a carbon chain with the structure −CO. They are named using the suffix -al. They are named using the suffix -one.

1. Which of the following statements are true? Select all that apply. Select one or more:...

1. Which of the following statements are true? Select all that apply. Select one or more: a. Earnings per share is calculated by dividing retained earnings by the number of shares of common stock outstanding. b. The creditors of a firm must be satisfied before any earnings can be distributed to the common shareholders. c. When referring to ratio comparisons, time-series analysis compares a firm to that of an industry leader. d. The operating profit margin must take into account...

Which 2 statements about management reports are true? (Select all that apply) A ) A management...

Which 2 statements about management reports are true? (Select all that apply) A ) A management report can be created from scratch. B ) Reports can be reordered by dragging the nine grid. C ) Previous year or period can be compared. D ) Brackets denote when QuickBooks Online pulls information from elsewhere. E ) Management reports can be shared with other companies by bookmarking the URL.

Which of the statements about plant cell walls is true? Select all that apply. The primary...

Which of the statements about plant cell walls is true? Select all that apply. The primary cell wall is thin and flexible, formed while the cells are still growing. In the late stages of cell division, the middle lamella is the first cell wall layer to be formed, serving to attach the daughter cells to each other. The secondary cell wall contains complex components such as lignin that are rigid. The cell wall has three layers: the middle lamella, the...

Which Of The Following Statements Are True? Select All That Apply. A. All other factors being...

Which Of The Following Statements Are True? Select All That Apply. A. All other factors being the same, dispersion forces between linear molecules are greater than dispersion forces between molecules whose shapes are nearly spherical. B. For the halogens, the dispersion forces increase while the boiling points decrease as you go down the column in the periodic table from F2 to I2 . C. For molecules with varying molecular weights, the dispersion forces may not become stronger as the molecules...

Which of the following statements is TRUE? Select all that apply. Marginal utility is the extra...

Which of the following statements is TRUE? Select all that apply. Marginal utility is the extra satisfaction a consumer realizes from an additional unit of that product. Total utility is the additional satisfaction or pleasure a person receives from consuming some specific quantity of a product. Marginal utility is the change in total utility that results from consuming 1 more unit of a product. To maximize satisfaction the consumer should allocate his or her money income so that the last...

Which of the following statements is TRUE? Select all that apply. A:The long run is a...

Which of the following statements is TRUE? Select all that apply. A:The long run is a period long enough for a firm to adjust the quantities of all the resources that it employs, including plant capacity. B:The long run is a period is a period too brief for a firm to alter its plant capacity, yet long enough to permit a change in the degree to which the plant’s current capacity is used. C:Average product is the extra output or...

Which of the following are TRUE about the Federal Funds Rate? (Select all that apply.) a....

Which of the following are TRUE about the Federal Funds Rate? (Select all that apply.) a. It is influenced by the Federal Reserve b. It is a rate at which banks can borrow long-term cash reserves c. It is set in the market d. It is the rate at which banks can borrow cash reserves on an overnight basis e. It is the rate at which individual investors may borrow cash from the Federal Reserve

1) Which of the following are TRUE about the process of translation? (Select all that apply)...

1) Which of the following are TRUE about the process of translation? (Select all that apply) Transcription factors attach to the mRNA to promote its circularization in the cytoplasm Binding of the large ribosomal subunit is the end of the initiation stage The third base of a codon permits wobble pairing Charged tRNAs enter the P site prior to being added to the protein chain There are three stages: initiation, elongation, and termination The process cannot be regulated until after...

Question