The first stage of cellular respiration is called_______1________.

In most living things a second stage of cellular respiration is called _______2___ __________, follows glycolysis. This requires _____3_____ and happens within ______4________.

a) oxygen

b) gycolysis

c) Oxidative respiration

d) mitochindria

STAGE 1: Glycolysis

Glycolysis is one of the __________ _____5_____ ___________ we know.

The word glycolysis means _____ _____6_____ __ ___________.

In a series of reactions, one molecule of glucose is split into smaller molecules of a compound called __________7 __________. Although cells must use some ___8__ to begin glycolysis, the process produces a little more __9___ than it uses.

a) The splitting of the glucose molecule

b) pyruvic acid

c) ATP

d) Oldest biological processes

For each molecule of glucose that enters glycolysis, a cell gains __10___ molecules of ATP.

During glycolysis, electrons carried on __11____ atoms are stripped from glucose molecules.. The ____12______ and ____13______ atoms are donated to an electron acceptor called ______14____forming the energy carrier _____15_____.

a) Hydrogen

b) 4

c) Electrons

d) NADH

e) NAD

For glycolysis to continue, however, electrons donated to __16___ to form ____17_____ must be donated to some other organic molecules.

This process frees the ___18______ to accept more electrons and _____19_____ atoms from glycolysis.

Thus, glycolysis is followed by another set of reactions either _____20_______ or__________21 __________ .

a) oxidative respiration

b) NADH

c) NAD

d) Hydrogen

e) fermentation

The pyruvic acid molecules made during _____22________ still contains ____23____, but they cannot be broken down further to release energy if no ____24______ is present

STAGE 2: Oxidative Respiration

. When the Earth’s _______25________ grew rich in ____26_____, an alternative to fermentation

became possible.

a) atmosphere

b) glycolysis

c) oxygen

d) energy

Oxidative respiration,

which happens within _______27________, was this alternative.

Oxidative respiration involves chemical reactions that make more ___28___ than is made by fermentation.

The complete breakdown of glucose through oxidative respiration can be summarized by the following equation: 29

As with the summary equation for photosynthesis, this equation does not show how cellular respiration happens. It merely indicates that the complete breakdown of glucose molecules uses __30___ oxygen atoms and forms __31___ carbon dioxide molecules, __32___ water molecules, and as many as __33___ ATP molecules.

a) ATP

b) C 6 H 12 O 6 + 6O---- 6CO 2 + 36ATP

c) Mitochondria

d) 6

e) 36

The electrons carried by molecules of __33___ formed during __________34 __________ are passed through a series of ____35______ in the _______36________ within the ________37__________.

a) NADH

b) Membranes

c) Proteins

d) Kreb’s cycle

e) Mitochondrion

This series of ____38______, called the ___________ _____39______ __________, uses ____40_______ of these _____41______ to pump ____42_____ across the membrane.

a) electron transport chain

b) energy

c ) proteins

d) electrons

e) protons

_____43_______ become highly concentrated on one side of the _______44________.

The ____45______ pass back though the _____46_______ by ____47______ through __________48 ___________.

a) diffusing

b) membrane

c ) proteins channels

d) protons

This movement of ____49______ supplies ____50______ needed to attach a _________________51 __________ to ___52___ molecule, making __53___.

a) Phosphate group

b) Protons

c) ATP

d) Energy

e) ADP

54. Most of the energy used by life on earth comes from a) the sun b) the rotation of the earth

c) the moon d) geothermal energy

55. The energy that is stored in food molecules and used by organisms a) resides in the nucleus

b) is equally distributed among all the atom’s electrons c) is held primarily by electrons shared by carbon and hydrogen atoms d) comes from protons orbiting the nucleus

56. Oxidation-reduction, redox, reactions are important in organisms because they a) allow the passage of energy from molecule to molecule b) prevent nuclear reactions from occurring

c) allow the creation and destruction of energy d) none of the above

57. Heterotrophs are organisms that can a) produce food from inorganic molecules and sunlight

b) survive without energy c) consume other organisms for energy d) carry out either photosynthesis or chemosynthesis

58. An enzyme a) is not used up when catalyzing a reaction b) acts to lower activation energy of a reaction c) bonds with a substrate molecule at the enzyme’s active site d) all of these

59. ATP a) contains 5 phosphate groups b) is essential for a cell to perform all the tasks necessary for life c) is found only in bacteria d) all of these

60. When living cells break down molecules, energy is a) stored as ADP b) stored as ATP

c) released as heat d) both b and c

61. ATP is called a cell’s energy currency because a) it catalyzes all metabolic reactions b) it allows one organelle to be exchanged for another between cells c) all molecules of glucose, a primary source of energy, are made of it d) most of the energy that drives metabolism is supplied by it.

62. When a phosphate group is transferred from an ATP molecule to another molecule

a) a substantial amount of energy is transferred as well b) an enzyme is formed c) the ATP molecule undergoes and endergonic change d) activation energy is increased

63. The process of cellular respiration a) is performed only by organisms that are incapable of photosynthesis b) breaks down food molecules to release the stored chemical energy c) occurs before plants are able to carry out photosynthesis d) occurs only in animals

64. In cellular respiration, a two carbon molecule combines with a four carbon molecule to form citric acid as part of a) glycolysis b) carbon fixation c) the Kreb’s Citric Acid cycle d) the electron transport system

65. When glycolysis occurs a) a molecule of glucose is split b) two molecules of pyruvic acid,pyruvate, are formed c) some ATP is produced d) all of the above

66. Fermentation is a) aerobic b) anaerobic c) chemosynthetic d) none of these

67. Which of the following is not formed during the Kreb’s cycle a) CO2 b) FADH2

c) NADH d) NADPH

68. Energetic electrons that provide the energy for the production of most of a cell’s ATP are carried to the electron transport system by a) ADP b) ATP c) NADH2 d) GDP

69. Alcohol or lactic acid are formed during a) cellular respiration b) fermentation c) glycolysis

d) Kreb’s Citric Acid cycle

70. Most of the CO2 from cellular respiration is released during a) glycolysis b) the Kreb’s cycle

c) lactate fermentation d) electron transport e) oxidative phosphorylation

71. Which of the following is a true distinction between fermentation and cellular respiration?

a) Only respiration oxidizes glucose

b) NADH is oxidized by the electron transport system only in respiration

c) Fermentation, but not respiration is an example of a catabolic pathway

d) NAD+ functions as an oxidizing agent only in respiration

72. Most of the ATP made during cellular respiration is generated by a) glycolysis b) oxidative phosphorylation c) substrate level Phosphorylation d) direct synthesis of ATP

73. When electron flow along the electron transport system of mitochondria, which of the following changes occur? a) The pH of the matrix increases b) The ATP synthase pumps protons by active transport c) The electrons gain free energy d) The cytochromes of the chain phophorylate ADP to ATP

74. In eucaryotic cells most of the enzymes of the Kreb’s cycle are located in the a) plasma membrane b) cytosol c) mitochondria d) chloroplast

75. Which metabolic pathway is common to both fermentation and cellular respiration? a) Kreb’s cycle b) electron transport system c) glycolysis d) synthesis of CoA

76. Fermentation and cellular respiration both take place in the absence of oxygen a) true b) false

77. Both prokaryotic and eucaryotic cells use ATP as an energy currency molecule a) true

b) false

78. Oxidative respiration must follow glycolysis if a cell is to maximize its ATP production

a) true B) false

79. ADP molecules have more potential energy than ATP a) true b) false

80. Cellular respiration is the antithesis of photosynthesis a) true b) false

81. Autotrophs are capable of producing their own food through the process of photosynthesis

a) true b) false

82. The main function of the Kreb’s cycle is to produce ATP’s directly a) true b) false

30. ATP is the universal energy molecule used by all living organisms a) true b) false

83. Describe completely and sequentially the process of glycolysis in cellular respiration.

( 10 points)

84. Describe completely and sequentially the Kreb’s citric acid cycle ( 10 points)

85. Describe completely and sequentially the electron transport system in cellular respiration.

10 points)

86. Summarize the ATP yield for each of the 3 phases of cellular respiration. (5 points)

87. Compare fermentation and cellular respiration. ( 5 points )