Chapter 6: Energy Flow in the Life of a Cell

1.	The laws of thermodynamics define the properties and behavior of energy. The first law states that energy __________. [Hint]
2.	Which of the following does NOT illustrate kinetic energy? [Hint]
3.	When electrical energy is used to turn on a lightbulb, the conversion from electrical energy to light energy is not 100% efficient. This loss of usable energy can be explained by __________. [Hint]
4.	The second law of thermodynamics relates the organization of matter to energy. It states that unless additional energy is acquired, the orderliness of a system tends to __________, whereas entropy __________. [Hint]
5.	In a chemical reaction, the __________ are the atoms or molecules that enter into the reaction, and the __________ are the chemicals or atoms produced by the reaction. [Hint]
6.	In endergonic reactions, __________. [Hint]
7.	Activation energy __________. [Hint]
8.	Energy from exergonic reactions is transferred from place to place in cells via __________. [Hint]
9.	The speed of a reaction is determined by its __________. [Hint]
10.	Enzymes are a class of proteins that catalyze chemical reactions in cells. Like all other catalysts, they speed up chemical reactions by __________. [Hint]
11.	Which of the following are correct statements about how enzymes work? [Hint]
12.	The most important reason a particular enzyme can function only within certain limits of temperature, salt conditions, and pH is that __________. [Hint]
13.	ATP is well suited to its role as an energy-carrier molecule in cells because __________. [Hint]
14.	A substance that is acted upon by an enzyme to produce a product is called a(n) __________. [Hint]
15.	Which of the following situations illustrates the coupling of exergonic to endergonic reactions in cells? [Hint]
16.	If all matter tends toward increasing randomness and disorder, how can life exist? [Hint]
17.	The amino acid threonine is converted to isoleucine by a sequence of five enzymatic reactions. When isoleucine levels are high, the first reaction in this sequence is “turned off.” This is an example of __________. [Hint]
18.	The laws of thermodynamics __________. [Hint]
19.	Why do most reactions occur more rapidly at high temperature? [Hint]
20.	Pepsin is an enzyme that breaks down protein but will not act upon starch. This fact is an indication that enzymes are __________. [Hint]
21.	Biological catalysts __________. [Hint]
22.	Which of the following is NOT used by an enzyme to promote a reaction? [Hint]
23.	Enzyme regulation can be precisely controlled through a variety of mechanisms such as __________. [Hint]
24.	Lysosomes have an acidic interior (pH = 5), unlike the rest of the cell (pH = 7). Lysosomal enzymes are most active at __________. [Hint]
25.	Which of the following is NOT true about enzymes? [Hint]
26.	The energy of movement is called . [Hint]
27.	Without energy, processes that proceed spontaneously result in an increase in . [Hint]
28.	A is a process that breaks and forms chemical bonds. [Hint]
29.	is the most common energy-carrier molecule in cells. [Hint]
30.	The of a cell is the sum of all of its chemical reactions. [Hint]
31.	are biological catalysts synthesized by living organisms. [Hint]
32.	Identify the compounds in the diagram below indicating the equation for energy storage. [Hint] For each item below, use the pull-down menu to select the letter that labels the correct part of the image. Choice A Choice B Choice C ATP Choice A Choice B Choice C ADP Choice A Choice B Choice C phosphate
33.	Identify the activation energy curves on the graph below. [Hint] For each item below, use the pull-down menu to select the letter that labels the correct part of the image. Choice A Choice B activation energy with catalyst Choice A Choice B activation energy without catalyst
34.	Label the structures associated with enzyme activity in the figure below. [Hint] For each item below, use the pull-down menu to select the letter that labels the correct part of the image. Choice A Choice B Choice C Choice D enzyme active site Choice A Choice B Choice C Choice D substrates Choice A Choice B Choice C Choice D product Choice A Choice B Choice C Choice D enzyme
35.	Using the same image as in Question 34, place the sequence of enzyme–substrate activity in the proper order. [Hint] For each item below, use the pull-down menu to select the letter that labels the correct part of the image. Choice A Choice B Choice C Substrates and the active site change shape, promoting reaction between the substrates. Choice A Choice B Choice C Substrates, bound together, leave enzyme as a product. Enzyme is ready for new substrates. Choice A Choice B Choice C Substrates enter the active site in a specific orientation.
36.	According to the first law of thermodynamics, the total amount of energy in the universe
37.	What is predicted by the second law of thermodynamics?
38.	Which statement about exergonic reactions is true?
39.	ATP is important in cells because
40.	How does an enzyme increase the speed of a reaction?
41.	Which of the following statements about enzymes is (are) true?
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