Biol2420 - From Cells To Systems #2: Cell Respiration

Front 1

What does the term metabolic pathway refer to?

Back 1

It means the sequence of chemical changes produced by a network of enzymes.

Hint 1

Pg. 037, 039

Front 2

What is the term that refers to the sequence of chemical changes produced by a network of enzymes that provides energy for the cell?

Back 2

Cell respiration

Hint 2

Pg. 037

Front 3

How is a portion of the energy captured in cellular respiration?

Back 3

It is captured in the chemical bonds that hold the last phosphate groups of the molecule of ATP.

Hint 3

Pg. 037

Front 4

What molecule functions as the universal energy carrier of the cell?

Back 4

ATP

Hint 4

Pg. 037

Front 5

What does the first law of thermodynamics state?

Back 5

Energy can neither be created nor destroyed.

Hint 5

Pg. 037

Front 6

What kind of energy is used to make ATP?

Back 6

Chemical bond energy

Hint 6

Pg. 037

Front 7

In general what is occurring in the process of photosynthesis?

Back 7

Plants use energy from sunlight to convert Carbon Dioxide and Water into Glucose.

Hint 7

Pg. 037

Front 8

What do scientists say regarding the molecule of Glucose compared to the molecules of Carbon Dioxide and Water?

Back 8

Scientists say glucose has more Free Energy or The Energy available to do work.

Hint 8

Pg. 037

Front 9

What is released when the chemical bonds formed by photosynthesis in glucose are broken?

Back 9

Energy is released in the form of heat.

Hint 9

Pg. 037

Front 10

What is the definition of one calorie?

Back 10

It is the amount of heat required to increase the temperature of 1 cubic centimeter of water 1 degree Celsius.

Hint 10

Pg. 037

Front 11

True or False, calories are used to measure the energy contained in food.

Back 11

False. kilocalories are the units used to measure the energy contained in food commonly expressed as Calories with a capital C.

Hint 11

Pg. 038

Front 12

In production of energy for the cell, approximately how much energy released escapes as heat?

Back 12

60%

Hint 12

Pg. 038

Front 13

What is an Exergonic reaction?

Back 13

It is the energy-releasing process, by breaking chemical bonds.

Hint 13

Pg. 038

Front 14

What does the exergonic process of the breakdown of food directly drive and what does this result in?

Back 14

It drives an Endergonic reaction. This then results in the addition of an inorganic phosphate group to the molecule of Adenosiine Diphosphate forming a molecule of Adenosine Triphosphate.

Hint 14

Pg. 038

Front 15

Approximately how much metabolic energy released is trapped in the phosphate bonds of ATP?

Back 15

40%

Hint 15

Pg. 038

Front 16

How does ATP provide energy?

Back 16

It provides energy when the chemical bond connecting the third phosphate to the other two phosphates is broken.

Hint 16

Pg. 038

Front 17

Why must cells produce their own ATP?

Back 17

Because, Organic molecules with phosphate groups are not able to pass through the plasma membranes of cells.

Hint 17

Pg. 038

Front 18

What term describes all the chemical changes that occur in our cells?

Back 18

Metabolism

Hint 18

Pg. 038

Front 19

What occurs at a branch point in a metabolic pathway?

Back 19

Two or more different enzymes use the same molecule as their substrate.

Hint 19

Pg. 039

Front 20

What can control the direction taken by a metabolic pathway?

Back 20

Gene activation/deactivation and Enzyme activation/deactivation.

Hint 20

Pg. 039

Front 21

What pathway converts a Glucose molecule into 2 molecules of Pyruvic Acid?

Back 21

Glycolysis

Hint 21

Pg. 040

Front 22

Where does the pathway occur that converts a glucose molecule into 2 molecules of Pyruvic Acid?

Back 22

In the cell’s Cytosol

Hint 22

Pg. 040

Front 23

What is pyruvic acid converted into in the absence of Oxygen?

Back 23

Lactic Acid

Hint 23

Pg. 040

Front 24

What is pyruvic acid converted into in the presence of Oxygen?

Back 24

Carbon Dioxide and Water

Hint 24

Pg. 040

Front 25

What does the first step in cellular respiration of Glucose produce?

Back 25

2 molecules of Pyruvic Acid or 2 3-carbon long molecules

Hint 25

Pg. 040

Front 26

How many useable “Universal energy carriers of the cell” are produced in Glycolysis?

Back 26

2 ATP

Hint 26

Pg. 040

Front 27

How many “Universal energy carriers of the cell” are produced in the first step of cellular respiration?

Back 27

4 ATP

Hint 27

Pg. 040

Front 28

What does the first step of cellular respiration produce besides the “Universal energy carriers of the cell?”

Back 28

2 NADH

Hint 28

Pg. 040

Front 29

How is NADH formed by Glycolysis?

Back 29

Glycolysis adds 2 Hydrogens to NAD.

Hint 29

Pg. 040

Front 30

What organelle is required for aerobic respiration?

Back 30

Mitochondria

Hint 30

Pg. 040

Front 31

What must occur in order for the first step of cellular respiration to continue?

Back 31

NADH must be converted back to NAD.

Hint 31

Pg. 041

Front 32

How is NADH converted back to NAD?

Back 32

NADH transfers hydrogens to another molecule.

Hint 32

Pg. 041

Front 33

How is lactic acid formed?

Back 33

It is formed in the absence of oxygen, and NADH transfers its hydrogen ions and electrons to pyruvic acid.

Hint 33

Pg. 041

Front 34

What kind of pathway converts glucose to lactic acid?

Back 34

Anaerobic pathway

Hint 34

Pg. 041

Front 35

The anaerobic pathway that produces lactic acid is also called __________________________.

Back 35

Lactic Acid Fermentation

Hint 35

Pg. 041

Front 36

What is the net gain of ATP per molecule of glucose made in lactic acid fermentation?

Back 36

2 ATP

Hint 36

Pg. 041

Front 37

How many molecules of Carbon Dioxide are released during Lactic Acid fermentation?

Back 37

Zero

Hint 37

Pg. 041

Front 38

What is pyruvic acid converted into in alcoholic fermentation?

Back 38

Ethyl Alcohol and Carbon Dioxide

Hint 38

Pg. 041

Front 39

How is Ethyl alcohol produced in alcoholic fermentation?

Back 39

How is Ethyl alcohol produced in alcoholic fermentation?

Hint 39

Pg. 041

Front 40

What is the terminal hydrogen ion electron acceptor in alcoholic fermentation?

Back 40

Acetaldehyde

Hint 40

Pg. 041

Front 41

What type of cell respiration produces the most amount of ATP?

Back 41

Aerobic Respiration

Hint 41

Pg. 041

Front 42

Where do the 2 3-carbon long molecules go once they have been produced in aerobic cellular respiration?

Back 42

The matrix of the mitochondria

Hint 42

Pg. 041

Front 43

What is produced once the molecules of pyruvic acid enters the matrix of the mitochondria?

Back 43

1 molecule of Carbon Dioxide per pyruvic acid.

Hint 43

Pg. 041

Front 44

Once a carbon has been removed from the 3-carbon long molecule, what does the remaining molecule combine with in the matrix of the mitochondria?

Back 44

It combines with a transfer molecule called Coenzyme A resulting in the Acetyl Coenzyme A or Acetyl CoA.

Hint 44

Pg. 041

Front 45

What is the process of converting Pyruvic Acid to Acetyl Coenzyme A called?

Back 45

Transition Reaction

Hint 45

Pg. 042

Front 46

How many Carbon Dioxide molecules are produced in the transition reaction for each glucose molecule?

Back 46

2 molecules of Carbon Dioxide

Hint 46

Pg. 042

Front 47

What happens to the carbons in the acetyl groups once they reach the Krebs cycle?

Back 47

They are released as carbon dioxide.

Hint 47

Pg. 042

Front 48

How many molecules of ATP are gained in the Citric Acid Cycle per molecule of glucose?

Back 48

2

Hint 48

Pg. 042

Front 49

What does each turn of the Krebs Cycle produce per glucose molecule?

Back 49

2 molecules of Carbon Dioxide
1 molecule of ATP
1 molecule FADH2
3 molecules of NADH+ H+

Hint 49

Pg. 042

Front 50

What is FAD derived from?

Back 50

Riboflavin - a B Vitamin

Hint 50

Pg. 042

Front 51

Where does the Krebs cycle occur?

Back 51

In the matrix of the mitochondria

Hint 51

Pg. 042

Front 52

Where does the final step of aerobic cellular respiration occur?

Back 52

The Cristae of the mitochondria or the folding of the inner mitochondrial membrane

Hint 52

Pg. 042

Front 53

What is the final step of aerobic cellular respiration called?

Back 53

The Electron Transport System or ETS or Electron Transport Chain or ETC

Hint 53

Pg. 042

Front 54

What transports the electrons to the electron transport chain?

Back 54

NADH and FADH2

Hint 54

Pg. 042

Front 55

What are many of the proteins in the Electron Transport Chain called and what do they contain?

Back 55

Cytochromes and they contain Iron

Hint 55

Pg. 042

Front 56

Where does the electron transport chain pump the hydrogen ions?

Back 56

Into the intermembranous space or the space between the outer and inner mitochondrial membranes.

Hint 56

Pg. 042

Front 57

What substance serves as the terminal hydrogen ion electron acceptor at the final step of aerobic cellular respiration?

Back 57

Oxygen

Hint 57

Pg. 042

Front 58

What substance is formed at the very last step of aerobic respiration?

Back 58

Water

Hint 58

Pg. 043

Front 59

Describe the events that occur during the last step of aerobic respiration.

Back 59

Hydrogen ions are moved from the intramembranous space into the matrix, this movement then powers an enzyme called ATP synthetase, this enzyme then catalyzes the conversion of ADP and Phosphate into ATP.

Hint 59

Pg. 043

Front 60

What is the production of ATP by means of the electron transport chain called?

Back 60

Oxidative Phosporylation

Hint 60

Pg. 043

Front 61

When there is a lack of oxygen what pathways in cellular respiration will be stopped?

Back 61

Transition Reaction
Krebs Cycle
And
Electron Transport Chain

Hint 61

Pg. 043

Front 62

What process is the only energy producing pathway active during the absence of oxygen?

Back 62

Gycolysis or Lactic Acid Fermentation

Hint 62

Pg. 043

Front 63

How many molecules of ATP are produced per molecule of glucose in the mitochondria?

Back 63

34-36 ATP molecules

Hint 63

Pg. 043

Front 64

Why are well-conditioned athletes much less likely to go into lactic acid fermentation?

Back 64

1) They have a higher number of mitochondria and are more able to rely on aerobic means of ATP generation.
2) Since there are a large number of mitochondria, they are able to start consuming oxygen as soon as the ADP concentration starts to rise, due to muscle contraction and the breakdown of ATP.
3) The faster rise in oxygen uptake at the onset of exercise means lactic acid fermentation production is less and will therefore require less oxygen needed to break down any accumulated lactic acid once they stop exercising.

Hint 64

Pg. 043

Front 65

True or False. Cell metabolism and the need for ATP are inversely related.

Back 65

False. The need for ATP is reduced when the cell temperature decreases.

Hint 65

Pg. 043

Front 66

What vessel brings blood sugar from the intestines to the liver?

Back 66

The Hepatic Portal Vein

Hint 66

Pg. 044

Front 67

What can the liver do if blood glucose concentration is high after a meal?

Back 67

It can remove a certain amount of blood glucose and convert it into polysaccharides (glycogen) and store it in the liver.

Hint 67

Pg. 044

Front 68

What protein is responsible for the movement of blood sugar into liver cells and skeletal muscles?

Back 68

Insulin

Hint 68

Pg. 044

Front 69

What is the only organ able to secrete glucose into the blood and what is this process called?

Back 69

The Liver

This process is called Glycogenolysis

Hint 69

Pg. 044

Front 70

True or False. The liver stores much more glycogen than do the skeletal muscles and this is one of the reasons why the liver is the only organ able to secrete glucose into the blood.

Back 70

False. The muscles store more glycogen collectively than the liver.

Hint 70

Pg. 044

Front 71

Why can’t the skeletal muscles secrete glucose into the blood?

Back 71

Because when glycogen is broken down, it forms glucose 6-phosphate, which is an organic molecule and organic molecules with phosphate groups cannot pass through a cell’s plasma membrane.

Hint 71

Pg. 044

Front 72

Why is the liver the only organ able to secrete glucose into the blood?

Back 72

Because it has Glucose 6- Phosphatase, an enzyme able to remove the phosphate group allowing the glucose to be able to enter the blood.

Hint 72

Pg. 044

Front 73

What are the 2 sources of blood glucose secretions?

Back 73

The Intestines and The Liver

Hint 73

Pg. 044

Front 74

From what source does the liver and resting skeletal muscles prefer to get their energy?

Back 74

From the aerobic respiration of fatty acids.

Hint 74

Pg. 044

Front 75

What type of tissue stores triglycerides as large fat droplets?

Back 75

Adipose Tissue

Hint 75

Pg. 044

Front 76

What enzyme is active when fat is being used for energy and what products does this enzyme produce?

Back 76

Lipase

A Triglyceride molecule is broken down into fatty acids and glycerol.

Hint 76

Pg. 045

Front 77

When a fatty acid is used for energy, what is the hydrocarbon chain is converted into?

Back 77

Acetyl CoA molecules

Hint 77

Pg. 045

Front 78

What are Glycerol molecules converted into when they are used for energy?

Back 78

Pyruvic Acid

Hint 78

Pg. 045

Front 79

How are proteins used for energy?

Back 79

Energy can be derived from amino acids obtained by food proteins or the break down of the body’s muscle proteins.

Hint 79

Pg. 045

Front 80

What are the amino acids of the hydrolyzed proteins converted into in order to be aerobically respired?

Back 80

1) Pyruvic Acid
2) Acetyl CoA
3) Isocitric acid (one of the Krebs cycle molecules)

Hint 80

Pg. 045

Front 81

What must be removed in order for amino acids to be used in order to aerobically produce energy?

Back 81

The Amine Group

Hint 81

Pg. 045

Front 82

What will be formed if the Amine group is allowed to enter the blood?

Back 82

Ammonia

Hint 82

Pg. 045

Front 83

What organ is responsible for detoxifying ammonia and what does it convert it into?

Back 83

The Liver

Urea a less toxic molecule.

Hint 83

Pg. 045