Nutr 130 - Chapter 7 - Metabolism

Front 1

What is metabolism?

Back 1

sum of all chemical and physical processes by which the body breaks down and builds up molecules

Front 2

why does every chemical reaction in the body either requires or releases energy?

Back 2

because cells throughout the body require chemical energy to grow, reproduce, and repair themselves, and maintain their functions.

Front 3

what is anabolism?

Back 3

process of building large molecules from smaller ones

Front 4

what kind of energy fuels anabolic reaction?

Back 4

chemical energy

Front 5

calorimeter measures food's what?

Back 5

caloric content

Front 6

what is catabolism?

Back 6

the breakdown or degradation of larger, more complex molecules to smaller, more basic molecules.

Front 7

T or F, catabolism requires chemical energy.

Back 7

False, catabolism releases chemical energy.

Front 8

Catabolism of food begin at which stage?

Back 8

digestion.

Front 9

What happens during digestion?

Back 9

chemical reaction break down proteins, lipids, and carbohydrates

Front 10

What are the end productions during the breakdown of the macro-nutrients during chemical reactions?

Back 10

amino acids, fatty acids, glycerol, and mono-saccharides (glucose)

Front 11

Catabolism of food begin at which stage?

Back 11

digestion.

Front 12

What happens during digestion?

Back 12

chemical reaction break down proteins, lipids, and carbohydrates

Front 13

What are the end productions during the breakdown of the macro-nutrients during chemical reactions?

Back 13

amino acids, fatty acids, glycerol, and mono-saccharides (glucose)

Front 14

After absorption what happens to the basic components?

Back 14

they are transported to body cells.

Front 15

what happens when the cells need energy?

Back 15

catabolizes the components into even smaller molecules, releasing energy.

Front 16

what is another use of catabolism?

Back 16

catabolism is also used to break down old cells or tissues that need to be repaired or replaced.

Front 17

how are catobolism and anabolism used together?

Back 17

energy gained via catabolic reaction is used not only to fuel the body's work, but also to build new compounds, cells, and tissues via anabolism.

Front 18

T or F, the energy to fuel anabolic reactions comes from the body's catabolic reactions

Back 18

True.

Front 19

Why is disease often dominated by catabolism?

Back 19

because more tissues are being broken down than repaired.

Front 20

Anabolism builds/repairs or breaks?

Back 20

builds/repairs

Front 21

what is ATP?

Back 21

an organic compound used by cells as a source of energy

Front 22

ATP includes what organic compound and how many ______ groups?

Back 22

adenosine and three phosphate groups.

Front 23

the bonds between the phosphate groups store significant amount of what?

Back 23

Potential energy sometimes termed high-energy phosphate bonds.

Front 24

why is ATP often called molecular "currency" of the cell?

Back 24

its phosphate bonds store energy to build new molecules, break down old molecules, and keep the cell functioning optimally.

Front 25

ATP does what kinds of things?

Back 25

contract a muscle (pick up a book, run a marathon), absorb calcium from our blood into a bone cell, to make insulin from amino acids

Front 26

what happens when one high energy phosphate bond is broken and a single phosphate group is released?

Back 26

Adenosine diphosphate (ADP) is produced.

Front 27

when two phosphates are removed, what is produced?

Back 27

adenosine monophosphate (AMP)

Front 28

How can ATP be regenerated?

Back 28

by adding phosphate groups back to the these molecules.

Front 29

what are metabolic pathways?

Back 29

chemical reactions that occur sequentially to achieve a particular goal

Front 30

T or F: breakdown of glucose for energy is an example of metabolic pathways.

Back 30

T

Front 31

T or F: Cells use different, yet related, metabolic pathways to release the energy in each of the major energy- containing nutrients?

Back 31

T

Front 32

What are the major energy-containing nutrients?

Back 32

Glucose, fatty acids, and amino acids.

Front 33

Why do different metabolic pathways typically occur within a specific part of a cell?

Back 33

because many metabolic enzymes are restricted to one or a few locations within the cell.

Front 34

Process of glycolysis occurs where?

Back 34

Cytosol

Front 35

which part of the cell is ATP produced?

Back 35

Mitochondria

Front 36

Which part of the cell is where chemical energy happens to produce energy?

Back 36

Mitochondria

Front 37

What is a cell that lacks the mitochondria? due to this, what ability do they lack?

Back 37

Red blood cells, they are limited to producing energy

Front 38

Red blood cells must rely on what to produce less efficient energy producing processes

Back 38

cytoplasm

Front 39

Where is glycogen stored?

Back 39

liver

Front 40

Explain the process how Glycogen is catabolized

Back 40

Glycogen stored in the liver catabolizes resulting glucose to release in the blood.

Front 41

Catabolism of muscle glycogen does not allow for the release of glucose into the blood, why is that?

Back 41

Muscle lacks one enzyme that catalyzes one simple step in the metabolic pathway that is found int he liver.

Front 42

Although all cells are metabolically active, in where are the key locations for the integration of metabolic pathways?

Back 42

liver, muscle, and adipose cells

Front 43

what are the five fundamental chemical reactions?

Back 43

Condensation, hydrolysis, phosphorylation, oxidation-reduction reactions, metabolic enzymes

Front 44

Condensation and Hydrolysis are chemical reactions involving what?

Back 44

water

Front 45

Is condensation anabolic or catabolistic process? Why?

Back 45

Anabolic process. Because it occurs when small chemically simple units combine to produce a larger more complex molecule.

Front 46

during the anabolic process in condensation, what is released as a by-product? what is another term used for this?

Back 46

water. dehydration synthesis

Front 47

What is the formula for condensation reactions?

Back 47

A-OH+H-B->A-B+H2O

Front 48

Hydrolysis is anabolic or catabolic?

Back 48

catabolic

Front 49

what happens during hydrolysis?

Back 49

large chemically complex molecules is broken apart with the addition of water.

Front 50

Hydrolysis is also called a ____ reaction. why?

Back 50

hydration reaction. Because the original molecule becomes hydrated.

Front 51

Formula for hydrolysis reaction:

Back 51

A--B+H2O--->A---OH+H---B (opposite of condensation)

Front 52

TF? The process by which phosphate is transferred is called phosphorylation.

Back 52

True

Front 53

Define phosphorylation in terms of phosphate gorup

Back 53

the addition of one or more phosphate groups to a chemical compound.

Front 54

TF? Glucose undergoes phosphorylation when it first enters a cell.

Back 54

True.

Front 55

What is the removable of a phosphate group as in the breakdown of ATP called?

Back 55

dephosphorylation

Front 56

when glucose is phosphorylated, it can be oxidized for energy or stored as what?

Back 56

glycogen

Front 57

Two things can happen when 2 high energy phosphate bonds in ATP is hydrolyzed:

Back 57

1. energy is released
2. phosphate is transferred to other molecules.

Front 58

TF? When glucose is phosphorylated, it can be oxidized for energy using the metabolic pathway _____ or stored as glycogen?

Back 58

Glycolysis

Front 59

What happens to the molecules in oxidation-reduction reactions?

Back 59

the molecules involved exchange electrons, often in the form of hydrogen.

Front 60

Why does the exchange of electrons occur together in oxidation reduction reactions?

Back 60

as electrons gained by one molecule be donated by another.

Front 61

What happens during oxidation-reduction reaction to the molecules when one molecule gives up electron while the other receives an electron?

Back 61

Molecule giving up an electron is oxidized. The molecules that's receiving the electron is reduced

Front 62

what does it mean when a molecule is "oxidized"?

Back 62

its electron is removed by oxygen

Front 63

what does it mean when a molecule is to be 'reduced"?

Back 63

in gaining an electron, it becomes more negatively charged.

Front 64

TF chemical reactions in living cells are not typically mediated by enzymes?

Back 64

False

Front 65

in order to function, enzymes generally require what two substances?

Back 65

coenzymes and cofactors

Front 66

Enzymes are proteins that do what during chemical reaction?

Back 66

accelerate the rate of a chemical reaction

Front 67

______ are non-protein substance that enhance or are required for enzyme activity.

Back 67

co-enzyme

Front 68

Cofactors are minerals such as ____ ___ ____ , which are required for enzyme activity

Back 68

iron, zinc, and magnesium

Front 69

TF? Vitamin B such as riboflavin, niacin, pantothenic acid, functions as coenzyme

Back 69

True.

Front 70

Does cofactor bind different parts of an enzyme together?

Back 70

Yes

Front 71

what kind of vitamins are required for metabolism?

Back 71

Vitamin B

Front 72

What is glucokinase?

Back 72

an enzyme that adds a phosphate group to a molecule of glucose

Front 73

most carbs are digested and absorbed as what?

Back 73

Glucose

Front 74

The three stages of oxidation of glucose is?

Back 74

1. glycolysis
2. TCA cycle (tricarboxylic acid) (kerbs cycle)
3. oxidative phosphorylation

Front 75

oxidative phosphorylation occurs in which chain?

Back 75

electron transport chain

Front 76

glycolysis is a sequence of chemical reactions that converts glucose into what?

Back 76

pyruvate

Front 77

glycolysis occurs in the mnitochondria or cytosol?

Back 77

cytosol

Front 78

During glycolysis, six carbon glucose is converted into how many molecules of three carbon pyruvate?

Back 78

2 molecules of 3 carbon pyruvate.

Front 79

in glycolysis, 1 glucose equals how many pyruvate?

Back 79

2

Front 80

glycolysis is the sole provider of what, in the the cells that lack mitochondria?

Back 80

ATP

Front 81

why is the process of glycolysis is one example of an oxidative pathway?

Back 81

because two hydrogen atoms are relased

Front 82

during glycolysis, the two hydrogen atoms that are released is picked up by what coenzyme?

Back 82

NAD (nicotinamide adenine dinucleotide)

Front 83

If the pyruvate molecules generated by glycolysis are to be used for the production of energy, they must go through a number of furthuer metabolic steps, which vary depending on whether oxygen is _______ or _______ (present or absent)

Back 83

aerobic, anerobic

Front 84

if energy is not immediately needed by the cell, pyruvate can be used to resynthesize glucose moving 'back up' this stage of the metabolic pathway through a seperate series of reaction... this reverse process is known as what?

Back 84

gluconeogenesis

Front 85

under conditions of oxygen absense (anaerobic), pyruvate is converted to what?

Back 85

lactate (lactic acid)

Front 86

the anaerobic conversions of pyruvate to lactate occurs where?

Back 86

few or no mitochondria such as red blood cells, lens and cornea of the eye...also muscle cells.

Front 87

in the presence of oxygen (aerobic), pyruvate is converted to a two carbon compound known as what?

Back 87

acetyl CoA

Front 88

where does the reaction of acetyl CoA occur?

Back 88

in mitochondria

Front 89

TF, when pyruvate is metabolized to acetyl CoA, theres no "going back" to glucose

Back 89

True

Front 90

the conversion of pyruvate to acetyl CoA is a critical step in the oxidation of glucose because it links stage which two steps?

Back 90

Glycolysis (stage 1) to (the TCA cycle ( stage 2)

Front 91

The prcess of glycolysis has a clear starting point of ______ and a clear ending point ________

Back 91

glucose to pyruvate

Front 92

TCA cycle occurs where in the cell?

Back 92

Mitochondria

Front 93

TCA cycle requires anerobic or aerobic?

Back 93

Aerobic pathways (needs oxygen)

Front 94

in the presence of oxygen; pyruvate is converted to what in the mitochondria?

Back 94

acetyl CoA

Front 95

what vitamin is Coenzyme a?

Back 95

B5

Front 96

TF: pyruvate crosses from teh cytosol into the mitochondria

Back 96

True

Front 97

absense of what nutrient will limit oxaloacetate and slows the TCA cycle?

Back 97

CHO

Front 98

in terms of grams, what is considered very low carbohydrate intake ?

Back 98

less than 20 grams/day

Front 99

The absense of CHO leads to build up acetyl coA and stimulates building of what?

Back 99

ketones

Front 100

the third and final stage of glucose oxidation, termed oxidative phosphorylation occurs where?

Back 100

in the electron transport chain

Front 101

where does the electron transport chain happen?

Back 101

inner membrane of the mitochondria

Front 102

Does the electron transport chain require oxygen (aerobic pathway)?

Back 102

yes

Front 103

additional water and ATP are produced as the electrons from what coenzyme are passed from one carrier to the next?

Back 103

NADH and FADH2

Front 104

glucose oxidation process started with glucose and ended with the production of what?

Back 104

Carbon dioxide, water, and ATP

Front 105

in glucose oxidation, the carbon dioxide was produced in the linking step of what?

Back 105

pyruvate and acetyl CoA and the TCA cycle

Front 106

Water was produced in the final step of the _______________

Back 106

electron transport chain

Front 107

converting triglycerides into energy are more complex than with glucose. what is the first step of turning triglycerides into energy?

Back 107

lipolysis ( fatty acid be removed from the glycerol backbone)

Front 108

Triglycerides in lipoproteins are broken down through the action of lipase?

Back 108

lipoprotein lipase

Front 109

triglycerides in adipose cells are catobolized by which enzyme?

Back 109

hormone-sensetive lipase

Front 110

fatty acids are attached to ____ which is a blood protein and later transported to working cells need of energy, such as muscle or liver cells.

Back 110

albumin

Front 111

Glycerol (fatty acids) cant be converted to glucose, they need to be first converted to ______ to be converted to acetyl coA or glucose

Back 111

pyruvate

Front 112

TF? when exercise stops, lactate leaves muscle cells and liver converts it to glucose

Back 112

True

Front 113

at the end of glucose oxidation, how many ATPS are yielded?

Back 113

36-38 ATP

Front 114

build up of what stimulates formation of ketones?

Back 114

aceytl CoA

Front 115

diabetes excess ketones is a sign of what in healthy humans?

Back 115

starvation

Front 116

How many grams of CHO is considered very low CHO intake?

Back 116

10-20 grams

Front 117

when the rate of ketone production increases above its use by cells, blood and urine ketone level rise, this condition is known as what?

Back 117

ketosis

Front 118

what is the typical blood level of ketones?

Back 118

3mg/dl

Front 119

body wants to eliminate the ketone through urine leading to what state?

Back 119

dehydration

Front 120

TF? Ketoacidosis occurs as the pH of the blood falls further and dehydration becomes more severe? This can lead to coma or death.

Back 120

True

Front 121

TF? Symptoms of diabetic ketoacidosis is fruity mouth order?

Back 121

True

Front 122

Proteolysis is what breakdown of macro nutrient, in which they are digested into single amino acids or small peptides that are absorbed into the body.

Back 122

protein

Front 123

if protein is consumed in excess of what is needed by the cells, some of this protein can be used for energy or converted into what for storage as triglycerides?

Back 123

fatty acids

Front 124

the body prefers using carbohydrates and fat for energy. protein is reserved for metabolic functions that cannot be performed by others, which is:

Back 124

building and repairing body tissues, and proteins are used for fuel during low total calorie intake or carb intake

Front 125

dietary proteins are digested into what two things?

Back 125

amino acids or small peptides

Front 126

amino acids are transported to the liver and made into what? (3 things)

Back 126

a) proteins such as albumin, liver proteins, enzymes... etc
b) released into the blood for uptake by other cells for building and repair functions
c) excess dietary protein is used for energy or converted to fatty acids for storage as triglycerides

Front 127

what does deamination mean?

Back 127

amine group is removed from carbon skeleton of amino acid

Front 128

when deamination happens, the carbon skeleton can then enter what?

Back 128

metabolic pathway

Front 129

TF? both dietary proteins and tissue proteins can be used for or stored as energy.

Back 129

True

Front 130

in deamination, what group is removed, leaving ammonia and a carbon skeleton?

Back 130

amino group

Front 131

Glucogenic amino acids are converted to what?

Back 131

pyruvate

Front 132

Ketogenic amino acids are converted directly to what?

Back 132

acetyl CoA

Front 133

TF? Many amino acids have multiple functions and contribute to TCA intermediates, glucose production, and ketone body production

Back 133

True

Front 134

What determines the amount of ATP produced?

Back 134

depends on where the carbons enter the metabolic pathway

Front 135

TF? No amino acid produces as much ATP as one glucose or fatty acid molecule

Back 135

True

Front 136

Where is the ammonia produced during protein catabolism converted ?

Back 136

urea in the liver and excreted as urine

Front 137

What is gluconeogenesis? It is making glucose from...?

Back 137

non-glucose substrates

Front 138

Are glucagon, epinephrine and cortisol anabolic hormones?

Back 138

No, they are catabolic hormones.

Front 139

what is lipogenesis?

Back 139

making fat from nonfat substances such as CHO, amino acids, and alcohol

Front 140

When does lipogenesis happen?

Back 140

1. occurs when consuming excess calories
2. acetyl CoA units assemble into fatty acid chain
3. Fatty acids combine with glycerol to form triglycerides
4. mostly occurs in the liver cells.

Front 141

What does amino acid synthesis means? explain what happens

Back 141

the body makes nonessential amino acids (NEAA)
1. amino group comes from transamination
2. synthesis of NEAA occurs only when the body has enough energy and nitrogen
3. since essential amino acids cannot be synthesized, they must be consumed in our diet.

Front 142

TF? Hormones regulate metabolism

Back 142

True

Front 143

is insulin the primary anabolic or catabolic hormone "building"?

Back 143

anabolic

Front 144

3 things insulin hormones does?

Back 144

1. increases in the blood after eating
2. activates storage enzymes
3. signals cellular uptake of glucose, fatty acids, and amino acids.

Front 145

TF glucagon, epinephrine and cortisol are catabolic hormones

Back 145

True

Front 146

what do glucagon, epinephrine and cortisol do?

Back 146

trigger the break down of stored triglycerides, glycogen, and body protein for energy