Biology 3 Ch 5 Energy and Life

Which of the following substances could be a cofactor? A) a ribosome B) a zinc atom C) a polypeptide D) a protein E) None of the choices are correct.

A zinc atom

What compound directly provides energy for cellular work? A) ATP B) sucrose C) DNA D) C6H12O6 E) fat

ATP

The region of an enzyme to which a substrate binds is called the ______ site. A) denatured B) enzymatic C) substrate D) active E) conformational

Active

Which of the following can affect the rate of an enzyme-catalyzed reaction? A) competitive inhibitors B) temperature C) noncompetitive inhibitors D) pH E) All of the choices are correct.

All of the choices are correct

Which of the following energy transfers is/are possible in living systems? A) light energy to potential energy B) light energy to chemical energy C) chemical energy to kinetic energy D) potential energy to kinetic energy E) All of the choices are correct.

All of the choices are correct

Heating inactivates enzymes by A) changing the enzyme's three-dimensional shape. B) causing enzyme molecules to stick together. C) breaking the covalent bonds that hold the molecule together. D) removing phosphate groups from the enzyme. E) None of the choices are correct.

Changing the enzyme's three-dimensional shape

Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are changing ______. A) kinetic energy into potential energy B) chemical energy into kinetic energy C) kinetic energy into chemical energy D) chemical energy into potential energy E) none of the above

Chemical energy into kinetic energy

How does inhibition of an enzyme-catalyzed reaction by a competitive inhibitor differ from inhibition by a noncompetitive inhibitor? A) Competitive inhibitors interfere with the enzyme; noncompetitive inhibitors interfere with the reactants. B) Competitive inhibitors bind to the enzyme reversibly; noncompetitive inhibitors bind to it irreversibly. C) Competitive inhibitors change the enzyme's tertiary structure; noncompetitive inhibitors cause polypeptide subunits to dissociate. D) Competitive inhibitors are inorganic substances such as metal ions; noncompetitive inhibitors are vitamins or vitamin derivatives. E) Competitive inhibitors bind to the active site of the enzyme; noncompetitive inhibitors bind to a different site.

Competitive inhibitors bind to the active site of the enzyme; noncompetitive inhibitors bind to a different site

The principle that energy cannot be created or destroyed is known as ______. A) entropy B) conservation of energy C) interconversion D) conservation of heat E) potential energy

Conservation energy

Living systems A) decrease their entropy while increasing the entropy of the universe. B) violate the second law of thermodynamics. C) are examples of a closed system. D) violate the first law of thermodynamics. E) None of the choices are correct.

Decrease their entropy while increasing the entropy of the universe

Which of the following is a measure of disorder? A) conservation of energy B) respiration C) potential energy D) kinetic energy E) entropy

Entrophy

Substances that plug up an enzyme's active site are ______. A) enzyme inhibitors B) reactants C) induced fit factors D) enzyme substrates E) enzyme products

Enzyme substrates

Which one of the following is true? A) Enzymes are used up in chemical reactions. B) An enzyme binds to its substrate at the enzyme's substrate site. C) An enzyme's function depends on its three-dimensional shape. D) Enzymes emerge changed from the reactions they catalyze. E) Enzymes work generally on a broad range of substrates.

Enzymes are used up in chemical reactions

What is the basic difference between exergonic and endergonic reactions? A) Exergonic reactions involve the breaking of bonds; endergonic reactions involve the formation of bonds. B) Exergonic reactions involve ionic bonds; endergonic reactions involve covalent bonds. C) Exergonic reactions involve the formation of bonds; endergonic reactions involve the breaking of bonds. D) In exergonic reactions, the reactants have less chemical energy than the products; in endergonic reactions, the opposite is true. E) Exergonic reactions release energy; endergonic reactions absorb it.

Exergonic reations release energy; endergonic reactions absorb it

When a cell uses chemical energy to perform work, it couples a(n) __________ reaction with a(n) __________ reaction. A) exergonic . . . spontaneous B) endergonic . . . exergonic C) exergonic . . . endergonic D) spontaneous . . . exergonic E) endergonic . . . spontaneous

Exergonic... endergonic

Bacterial production of the enzymes needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example of A) competitive inhibition. B) irreversible inhibition. C) noncompetitive inhibition. D) feedback inhibition. E) positive feedback.

Feedback inhibition

When an enzyme catalyzes a reaction, A) it raises the activation energy of the reaction. B) it becomes a product. C) it lowers the activation energy of the reaction. D) it acts as a reactant. E) None of the choices are correct.

It lowers the activation energy of the reaction

You are riding on your bike and stop pedaling, coasting along the road. Eventually, your bike slows down and stops. What happened to the energy of your motion when your bike stopped? A) It was converted back to chemical energy. B) It was used to chemically break down the tires. C) It was released as heat. D) It was stored as kinetic energy. E) It was returned to the bicycle.

It was stored as kinetic energy

Which one of the following is most similar to the mechanism of an enzyme inhibitor? A) forgetting to put a cap back on a pen B) keeping someone from parking by parking in their designated spot C) combining new ingredients in a new recipe D) changing the tires on a car E) driving the wrong way on a one-way street

Keeping someone from parking by parking in their designated spot

The energy of motion is ______ energy. A) conserved B) kinetic C) stored D) potential E) created

Kenetic

Kinetic energy differs from chemical energy in that A) kinetic energy can be converted into various forms of energy, whereas chemical energy can only be converted into heat. B) kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules. C) chemical energy is a particular form of kinetic energy. D) kinetic energy is stored energy that has the potential to do work, and chemical energy is the energy of movement. E) kinetic energy depends on the movement of atoms, whereas chemical energy depends on the movement of molecules.

Kenetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules

The sum total of all the chemical reactions that occur in organisms is called ______. A) replication B) summation C) cellular synthesis D) inheritance E) metabolism

Metabolism

Energy is transferred from ATP to other molecules by transferring a(n) ______. A) spring B) heat unit C) photon D) adenosine E) phosphate group

Phosphate group

A rock on the top of a mountain contains ______ energy. A) no B) kinetic C) motion D) conserved E) potential

Potential

Anything that prevents ATP formation will most likely ______. A) have no effect on the cell B) result in cell death C) result in the conversion of kinetic energy to potential energy D) force the cell to rely on lipids for energy E) force the cell to rely on ADP for energy

Result in cell death

The ultimate source of nearly all energy available to life on Earth is A) photosynthesis. B) electricity. C) wind. D) sunlight. E) cellular respiration.

Sunlight

What is energy? A) the capacity to perform work B) a measure of disorder C) a measure of calories D) metabolism E) the capacity to cause movement

The capacity to perform work

According to __________, energy cannot be created or destroyed. A) the third law of thermodynamics B) Einstein's law of relativity C) Aristotle's first principle D) the second law of thermodynamics E) the first law of thermodynamics

The first law of thermodynamics

The active site of an enzyme is A) the region of a substrate that is changed by an enzyme. B) the highly changeable portion of an enzyme that adapts to fit the substrates of various reactions. C) the region of an enzyme that attaches to a substrate. D) the region of a product that detaches from the enzyme. E) None of the choices are correct.

The region of an enzyme that attaches to a substrate

Which one of the following processes is endergonic? A) the release of heat from the breakdown of glucose B) the breakdown of glucose C) cellular respiration D) the synthesis of glucose from carbon dioxide and water E) the burning of wood

The synthesis of glucose from carbon dioxide and water