Biology Chapter 8 Flashcards
42 Questions
100 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of these is exhibiting kinetic energy?

  • A space station orbiting Earth (correct)
  • An archer with a flexed bow
  • The high-energy phosphate bonds of a molecule of ATP
  • A rock on a mountain ledge
  • A person sitting on a couch while watching TV

    • "Conservation of energy" refers to the fact that _____

  • If you conserve energy you will not be as tired
  • Energy cannot be created or destroyed but can be converted from one form to another (correct)
  • The entropy of the universe is always increasing
  • No chemical reaction is 100 percent efficient
  • The net amount of disorder is always increasing

    • Chemical energy is a form of _____ energy.

  • Potential (correct)
  • Motion
  • Kinetic
  • Entropic
  • Heat

    • In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?

    <p>Cellular respiration</p> Signup and view all the answers

    Which of these are by-products of cellular respiration?

    <p>Heat, carbon dioxide, and water</p> Signup and view all the answers

    Which of the following statements about the combustion of glucose with oxygen to form water and carbon dioxide is correct?

    <p>The entropy of the products is greater than the entropy of the reactants.</p> Signup and view all the answers

    Which of the following statements about equilibrium of chemical reactions is correct?

    <p>A reaction that is at equilibrium is not capable of doing any work.</p> Signup and view all the answers

    In this reaction (Reactants AB + CD --> AC + BD), what is correct?

    <p>The products have less potential energy than the reactants</p> Signup and view all the answers

    In this reaction (Reactants AB + CD --> AC + BD), what is correct?

    <p>Heat has been released to the environment</p> Signup and view all the answers

    The following reaction A --> B + C + heat is a(n) _____ reaction.

    <p>Exergonic</p> Signup and view all the answers

    A(n) _____ reaction occurs spontaneously.

    <p>Exergonic</p> Signup and view all the answers

    Which of these reactions requires a net input of energy from its surroundings?

    <p>Endergonic</p> Signup and view all the answers

    In cells, what is usually the immediate source of energy for an endergonic reaction?

    <p>ATP</p> Signup and view all the answers

    The reaction ADP + P --> ATP is a(n) _____ reaction.

    <p>Endergonic</p> Signup and view all the answers

    The energy for an endergonic reaction comes from a(n) _____ reaction.

    <p>Exergonic</p> Signup and view all the answers

    What is the fate of the phosphate group that is removed when ATP is converted to ADP?

    <p>It is acquired by a reactant in an endergonic reaction.</p> Signup and view all the answers

    The graph illustrates a(n) _____ reaction (Reactants have less energy than products)

    <p>Endergonic</p> Signup and view all the answers

    Select the INCORRECT association.

    <p>Exergonic...uphill</p> Signup and view all the answers

    What is energy coupling?

    <p>The use of energy released from an exergonic reaction to drive an endergonic reaction</p> Signup and view all the answers

    What makes up an ATP (Adenosine Triphosphate) molecule?

    <p>3 phosphate groups, a ribose group (pentagon), and an adenine group (double ring).</p> Signup and view all the answers

    What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?

    <p>Hydrolysis</p> Signup and view all the answers

    Which has a lower reaction rate?

    <p>Uncatalyzed reaction</p> Signup and view all the answers

    An enzyme is ______ when it loses its native conformation and its biological activity.

    <p>Denatured</p> Signup and view all the answers

    An enzyme is considered a ______ because it speeds up chemical reactions without being used up.

    <p>Catalyst</p> Signup and view all the answers

    An enzyme is considered _____ because of its ability to recognize the shape of a particular molecule.

    <p>Specific</p> Signup and view all the answers

    A ______, such as a vitamin, binds to an enzyme and plays a role in catalysis.

    <p>Cofactor</p> Signup and view all the answers

    When properly aligned, the enzyme and substrate form an enzyme-substrate (ES) _____

    <p>Complex</p> Signup and view all the answers

    A substrate binds to an enzyme at the ________, where the reaction occurs.

    <p>Active site</p> Signup and view all the answers

    In a catalyzed reaction, a reactant is often called a _____

    <p>Substrate</p> Signup and view all the answers

    In which region does the reaction rate remain constant?

    <p>Region C</p> Signup and view all the answers

    In which region is the enzyme saturated with substrate?

    <p>Region C</p> Signup and view all the answers

    Consider a situation in which the enzyme is operating at optimum temperature and pH, and has been saturated with substrate. What is your best option for increasing the rate of the reaction?

    <p>Increase the enzyme concentration.</p> Signup and view all the answers

    A(n) ________ inhibitor has a structure that is so similar to the substrate that it can bond to the enzyme just like the substrate.

    <p>Competitive</p> Signup and view all the answers

    A(n) ________ inhibitor binds to a site on the enzyme that is not the active site.

    <p>Noncompetitive</p> Signup and view all the answers

    Usually, a(n) ________ inhibitor forms a covalent bond with an amino acid side group within the active site, which prevents the substrate from entering the active site or prevents catalytic activity.

    <p>Irreversible</p> Signup and view all the answers

    The competitive inhibitor competes with the substrate for the _______ on the enzyme.

    <p>Active site</p> Signup and view all the answers

    When the noncompetitive inhibitor is bonded to the enzyme, the shape of the ______ is distorted.

    <p>Enzyme</p> Signup and view all the answers

    Enzyme inhibitors disrupt normal interactions between an enzyme and its _____

    <p>Substrate</p> Signup and view all the answers

    You have added an irreversible inhibitor to a sample of enzyme and substrate. At this point, the reaction has stopped completely. What can you do to regain the activity of the enzyme?

    <p>The enzyme is inactive at this point. New enzyme must be added to regain enzyme activity.</p> Signup and view all the answers

    You have an enzymatic reaction proceeding at the optimum pH and optimum temperature. You add a competitive inhibitor to the reaction and notice that the reaction slows down. What can you do to speed the reaction up again?

    <p>Add more substrate; it will outcompete the inhibitor and increase the reaction rate.</p> Signup and view all the answers

    Which of the following statements is most likely to be true in the case of the feedback-regulated enzymatic pathway shown?

    <p>P4 binds E1 and deactivates it.</p> Signup and view all the answers

    Which of the following statements about feedback regulation of a metabolic pathway is correct?

    <p>The final product of a metabolic pathway is usually the compound that regulates the pathway.</p> Signup and view all the answers

    Study Notes

    Kinetic and Potential Energy

    • Kinetic energy is exemplified by a space station orbiting Earth.
    • Chemical energy is identified as a form of potential energy.
    • The conversion of chemical energy in glucose to ATP occurs via cellular respiration.

    Energy Conservation and Thermodynamics

    • Conservation of energy means energy cannot be created or destroyed, only converted between forms.
    • Cellular respiration results in by-products including heat, carbon dioxide, and water.
    • The entropic state increases as the reaction involving glucose combustion generates greater entropy among products.

    Chemical Reactions and Equilibrium

    • At equilibrium, reactions are unable to do work; a system at this state is stable but inactive.
    • Exergonic reactions yield products with less potential energy and release heat to the environment.
    • Endergonic reactions require an input of energy from their surroundings to proceed.

    ATP and Energy Coupling

    • ATP (Adenosine Triphosphate) consists of three phosphate groups, a ribose group, and an adenine group.
    • The hydrolysis of ATP to ADP is an exergonic reaction that provides energy for endergonic processes.
    • Energy coupling describes the harnessing of energy from exergonic reactions to drive endergonic reactions.

    Enzyme Structure and Function

    • Enzymes serve as catalysts, accelerating reactions without being consumed.
    • A substrate binds at the active site on the enzyme where the reaction occurs, forming an enzyme-substrate complex.
    • Enzymes demonstrate specificity, recognizing particular substrates due to their three-dimensional shape.

    Inhibition and Regulation of Enzymatic Activity

    • Competitive inhibitors mimic substrates, binding to active sites and hindering substrate access.
    • Noncompetitive inhibitors bind at sites other than the active site and alter enzyme activity without competing for the substrate.
    • Irreversible inhibitors covalently bond with the enzyme, permanently blocking activity.

    Factors Affecting Enzyme Activity

    • Reaction rates can be enhanced by increasing enzyme concentration when operating at saturation.
    • The enzyme’s shape is modified by noncompetitive inhibitors, impacting its ability to function.
    • Optimal conditions (temperature and pH) are critical for enzyme performance; deviations can lead to inactivation.

    Feedback Mechanisms in Metabolism

    • Feedback regulation involves the final product of a pathway sometimes inhibiting the initial enzyme, maintaining homeostasis.
    • The compound regulating the pathway often acts as a competitive inhibitor or an allosteric regulator, influencing metabolic flow.
    • Products of metabolic pathways can act as reactants in subsequent reactions to prevent accumulation.

    Graph Interpretation

    • Regions on a reaction rate curve indicate different enzyme saturations with substrates, impacting reaction speeds.
    • Reaction rates plateau when enzymes are saturated, unable to process additional substrate.
    • Adding more substrate to compensate for a competitive inhibitor can restore reaction rates.
    • When reaction activity halts due to irreversible inhibition, the introduction of new enzyme is necessary for resuming function.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Test your knowledge of key concepts in Chapter 8 of Mastering Biology with these flashcards. This quiz covers important topics such as kinetic energy and the conservation of energy. Enhance your understanding and retention of biological principles through these engaging questions.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser