CH 8 Sapling HW

What is energy? a) the heat required to raise a substance's temperature b) the ability of a system to preform work c) the transfer of heat btwn two objects d) the frequency at which an atom vibrates

b) the ability of a system to preform work

You have been hired to develop a durg to inhibit the action of a certain enxyme. Where should the drug bind to allosterically inhibit the enzyme? a) to the substrate of the enzyme b) to the mRNA that encodes the enzyme c) to the active site of the enzyme d) to a site on the enzyme other than the active site

d) to a site on the enzyme other than the active site

Which are examples of competitive inhibition? a) Ethanol out competes ethylene for binding to the enzyme alchol dehydrogenase b) Ibuprofen binds tightly to the active site of COX enzymes instead of the natural substrate c) Isoleucine inhibits an enzyme by binding to a protein domain that does not include the active site d) Adenosine triphosphate (ATP) prevents the synthesis of additional ATP by binding to a regulatory domain that is separate from its catalytic domain

a) Ethanol out competes ethylene for binding to the enzyme alchol dehydrogenase b) Ibuprofen binds tightly to the active site of COX enzymes instead of the natural substrate

Which are forms of Potential energy? a) Glucose stored in liver cells b) ATP c) cell movement d) vesical transport in a cell

a) Glucose stored in liver cells b) ATP

Which of the following represent an catabolic pathway? a) Glycolysis converts 1 molecule of glucose to 2 molecules of pyruvate b) A nucleic acid molecule is broken down into nucleotide subunits c) A protein molecule is constructed from amino acid subunits d) Photosynthesis generates storage carbohydrates from CO2 and H2O

a) Glycolysis converts 1 molecule of glucose to 2 molecules of pyruvate b) A nucleic acid molecule is broken down into nucleotide subunits

An enzyme catalyzes a reaction in a way that results in a lower activation energy. What is the significance of a lower activation energy? a) It increases the rate of cellular reaction b) It slows the reaction, preventing metabolic mistakes c) It increases overall cellular energy expenditure d) It increases the rate at which enzymes are consumed

a) It increases the rate of cellular reaction

Why are ezymes required for cellular metabolic pathways? a) The enzymes that are present in a cell determine which metabolic reactions can occur in the cell b) A cell can regulate metabolic pathways by controlling the enzyme concentration in the cell c) A single enzyme can convert onc substrate into many different products d) An enzyme lowers the activation emergy and therefore increases the rate of reaction e) Enzymes are consumed by metabolic pathways when reactants are converted into products

a) The enzymes that are present in a cell determine which metabolic reactions can occur in the cell b) A cell can regulate metabolic pathways by controlling the enzyme concentration in the cell d) An enzyme lowers the activation emergy and therefore increases the rate of reaction

Feedback inhibition is important for the regulation of many metabolic pathways. Which of the statements are examples of feedback inhibition? a) The production of isoleucine is halted by the presence of excess isoleucine b) The last enzyme in glycolysis is activated by the intermediates of glycolysis c) The beginning of glycolysis is inhibited by high levels of ATP in the cell d) The lac operon is not transcribed when there is no lactose present

a) The production of isoleucine is halted by the presence of excess isoleucine c) The beginning of glycolysis is inhibited by high levels of ATP in the cell

Which phrases represent enzymes? a) a biological catalyst b) a protein containng an active site c) a specific enzyme location that binds with the substance d) a substance that the enzyme acts upon e) may be a phosphate group

a) a biological catalyst b) a protein containng an active site

Which of these describes a catabolic pathway? a) a pathway that breaks down molecules into smaller subunits b) a pathway that transmits a signal into a cell c) a pathway that constructs molecules from smaller subunits c) a pathway that consumes energy

a) a pathway that breaks down molecules into smaller subunits

Which statements describe Endergonic? a) generating carbs in photosynthesis b) pedaling a bike up a steep hill c) constructing DNA from molecules d) a ball rolling down a hill e) breaking down glucose in cellular respiration f) metabolizing proteins into amino acids

a) generating carbs in photosynthesis b) pedaling a bike up a steep hill c) constructing DNA from molecules

Which statements describe a catalyst? a) is not consumed during the chemical reaction b) is a protein that functions in a metabolic reaction c) lowers the activation energy of a chemical raction d) increases the rate of exergonic reactions e) increases the energy difference btwn reactants and products

a) is not consumed during the chemical reaction c) lowers the activation energy of a chemical raction d) increases the rate of exergonic reactions

If a drug binds to an enzyme and allosterically inhibits the action of the enzyme, which statements are true regarding the enzyme? a) the drug will decrease the binding affinity of the substrate to the active site of the enzyme b) the drug will bind to the enzyme at a site other than the active site, and the conformation of the active site will change. c) the drug will bind in the active site of the enzyme, and the conformation of the active site will change d) the allosteric site is only used to help enzymes bind to membranes, and the drug will not affect the action of the enzyme

a) the drug will decrease the binding affinity of the substrate to the active site of the enzyme b) the drug will bind to the enzyme at a site other than the active site, and the conformation of the active site will change.

Which molecule is used as the primary source of cehmical energy for tasks within a cell? a) NADH b) ATP c) Glucose d) Phospholipids

b) ATP

Where is chemical energy stored in ATP? a) the hydroxyl group that react with other molecules to release energy b) the phosphate groups that repel each other bc of negatively charged atoms c) the ribose sugar that is unstable due to its ring shaped structure

b) the phosphate groups that repel each other bc of negatively charged atoms

You have been hired to develop a drug to inhibit the action of a certain enzyme. Where should the drug bind to competitively inhibit the enzyme? a) to a site on the enzyme other than the active site b) to the active site of the enzyme c) to the substrate of the enzyme d) to the mRNA that encodes the enzyme

b) to the active site of the enzyme

Which of the following represent an anabolic pathway? a) Glycolysis converts 1 molecule of glucose to 2 molecules of pyruvate b) A nucleic acid molecule is broken down into nucleotide subunits c) A protein molecule is constructed from amino acid subunits d) Photosynthesis generates storage carbohydrates from CO2 and H2O

c) A protein molecule is constructed from amino acid subunits d) Photosynthesis generates storage carbohydrates from CO2 and H2O

Which of the choices are examples of coupled reactions? a) Lactose hydrolysis by water results in glucose and galactose b) ATP is hydrolyzed by water without the presence of enzymes c) ATP hydrolysis drives sucrose synthesis from glucose and fructose d) ATP synthesis is driven by a proton gradient fromed in the mitochondria e) In water, soduim chloride (NaCl) dissociates into sodium and chloride ions.

c) ATP hydrolysis drives sucrose synthesis from glucose and fructose d) ATP synthesis is driven by a proton gradient fromed in the mitochondria

Asprin is an enxyme inhibiting drug that targets the inflammation response of the body after an injury. The inflammation response is triggered by prostaglandins, which are synthesized from essential fatty acids by cyclooxygenase enzymes. How does asprin suppress the inflammation response? a) Asprin signals the cells of the body to stop producing the cyclooxgenase enzymes b) Asprin binds to the prostaglandins, preventing them from triggering the immune response c) Asprin binds to the cyclooxgenase enzymes, preventing the synthesis of prostaglandins d) Asprin binds to the essential fatty acids, preventing their conversion to prostaglandins

c) Asprin binds to the cyclooxgenase enzymes, preventing the synthesis of prostaglandins

Which are examples of allosteric inhibition? a) Ethanol out competes ethylene for binding to the enzyme alchol dehydrogenase b) Ibuprofen binds tightly to the active site of COX enzymes instead of the natural substrate c) Isoleucine inhibits an enzyme by binding to a protein domain that does not include the active site d) Adenosine triphosphate (ATP) prevents the synthesis of additional ATP by binding to a regulatory domain that is separate from its catalytic domain

c) Isoleucine inhibits an enzyme by binding to a protein domain that does not include the active site d) Adenosine triphosphate (ATP) prevents the synthesis of additional ATP by binding to a regulatory domain that is separate from its catalytic domain

Which statement best describes a metabolic pathway? a) a chemical reaction that makes or breaks down molecules b) the set of molecular reactions in which enzymes make or break down sugars c) a linked sequence of chemical reactions caralyzed by specific enzymes d) chemical reactions that do not use specific enzymes and are necessary for normal bodily functions

c) a linked sequence of chemical reactions caralyzed by specific enzymes

Which phrases represents an active site? a) a biological catalyst b) a protein containg an active site c) a specific enzyme location that binds with the substance d) a substance that the enzyme acts upon e) may be a phosphate group

c) a specific enzyme location that binds with the substance

Which are forms of kinetic energy? a) Glucose stored in liver cells b) ATP c) cell movement d) vesical transport in a cell

c) cell movement d) vesical transport in a cell

What is free energy (G)? a) the energy released in a chemical reaction b) the energy of objects in motion c) the energy that may be used to preform work d) the total energy of a system

c) the energy that may be used to preform work

How does the shape of a competitive enzyme inhibitor determine its mechanism of inhibition? a) the inhibitor and substrate are similar in shape. The active site of the enzyme binds to both the inhibitor and the substrate, inactivating the enzyme. b) the inhibitor and substrate have different shapes. An allosteric site on the enzyme binds to the inhibitor, which prevents the active site from binding with the substrate. c) the inhibitor and substrate are similar in shape. The active site of the enzyme binds to the inhibitor instead of the substance d) the inhibitor and substrate have different shapes. The active site of theenzyme binds to both the inhibitor and the substrate, inactivating the enzyme.

c) the inhibitor and substrate are similar in shape. The active site of the enzyme binds to the inhibitor instead of the substance

Keeping in mind that enzymes are proteins, pick the best reason why enzyme function declines above a certain temperature. a) The amino acid sequence of the folded enzyme is modified by heat b) The hydrogen bonds btwn DNA strands are broken by heat c) Substrate molecules slow down as temp increases d) The enzyme unfolds at high temps as hydrogen bonds break

d) The enzyme unfolds at high temps as hydrogen bonds break

Which statements describe Exergonic? a) generating carbs in photosynthesis b) pedaling a bike up a steep hill c) constructing DNA from molecules d) a ball rolling down a hill e) breaking down glucose in cellular respiration f) metabolizing proteins into amino acids

d) a ball rolling down a hill e) breaking down glucose in cellular respiration f) metabolizing proteins into amino acids

Which of these describes and anabolic pathway? a) a pathway that transmits a signal within a cell b) a pathway that breaks down molecules into smaller subunits c) a pathway that generates ATP d) a pathway that generated molecules from smaller subunits

d) a pathway that generated molecules from smaller subunits

Which phrases represent substrates? a) a biological catalyst b) a protein containng an active site c) a specific enzyme location that binds with the substance d) a substance that the enzyme acts upon e) may be a phosphate group

d) a substance that the enzyme acts upon e) may be a phosphate group