ch 4 metabolism

Question 1

metabolism

Answer 1

all of the chemical reactions that occur in the body

Question 2

two types of metabolism

Answer 2

catabolism
anabolism

Question 3

catabolism

Answer 3

chemical reactions that break down complex organic molecules into smaller molecules
- exergonic

Question 4

anabolism

Answer 4

chemical reactions that combine smaller molecules to form larger, more complex molecules

Question 5

energy

Answer 5

the capacity to do work

Question 6

two principle forms of energy

Answer 6

potential energy
kinetic energy

Question 7

potential energy

Answer 7

energy stored by matter due to its position

Question 8

kinetic energy

Answer 8

energy associated with matter in motion

Question 9

chemical energy

Answer 9

a form of potential energy that is stored in the bonds of compounds and molecules

Question 10

law of conservation of energy

Answer 10

energy can neither be created nor destroyed, it may be converted from one form to another

Question 11

exergonic reactions

Answer 11

release more energy than they absorb

Question 12

endergonic reactions

Answer 12

absorb more energy than they release

Question 13

activation energy

Answer 13

collision energy needed to break the chemical bonds of the reactants

Question 14

catalysts

Answer 14

chemical compounds that speed up chemical reactions by lowering the activation energy needed for a reaction to occur

Question 15

enzyme

Answer 15

catalyze chemical reactions

Question 16

substrates

Answer 16

the reactant molecules on which an enzyme acts

Question 17

ligand

Answer 17

a molecule that binds to a particular site on a protein

Question 18

three major properties of enzymes

Answer 18

highly specific
very efficient
subject to a variety of controls

Question 19

active site

Answer 19

the part of the enzyme that catalyzes the reaction

Question 20

lock-and-key model

Answer 20

the active site fits the substrate like a key fits a lock

Question 21

induced-fit model

Answer 21

the active site slightly changes its shape to fit snugly around the substrate after the substrate enters the active site

Question 22

cofactor

Answer 22

help the enzyme’s active site form the correct shape for substrate binding or they participate in the reaction catalyzed by the enzyme

Question 23

coenzyme

Answer 23

cofactor that is an organic molecule; often derived from vitamins

Question 24

factors that affect the rate of an enzyme-catalyzed reaction

Answer 24

temp
ph
the substrate concentration
nonsubstrate chemical substance that binds to the enzyme

Question 25

competitive inhibitor

Answer 25

a chemical substance that resembles the substrate and binds reversibly to the active site of the enzyme

Question 26

allosteric modulator

Answer 26

chemical substance that binds reversibly to the allosteric site which causes a conformational change of the enzyme that alters the affinity of the active site for the substrate

Question 27

allosteric activator

Answer 27

binding to an allosteric site causes a conformational change of the enzyme that increases the affinity of the active site for the substrate

Question 28

allosteric inhibitor

Answer 28

binding to an allosteric site causes a conformational change in the enzyme that decreases the affinity of the active site for the substrate

Question 29

metabolic pathway

Answer 29

a sequence of reactions in which an initial substrate is converted into an end product via a series of intermediates

Question 30

feedback inhibition

Answer 30

the end product of a metabolic pathway shuts down the pathway by binding to and inhibiting an enzyme that catalyzes one of the earlier reactions of the pathway

Question 31

phosphorylation

Answer 31

addition of a phosphate group to a molecule

Question 32

two mechanisms of phosphorylation to generate ATP

Answer 32

1. substrate-level 2. oxidative

Question 33

substrate-level phosphorylation

Answer 33

generate ATP by transferring a phosphate group from a phosphorylated metabolic intermediate directly to ADP

Question 34

oxidative phosphorylation

Answer 34

produce ATP by adding a phosphate group to ADP using energy derived from a series of electron carriers with oxygen serving as the final electron acceptor

Question 35

cellular respiration

Answer 35

the process by which a nutrient molecule is broken down in the presence of oxygen to form carbon dioxide, water, and energy

Question 36

four sets of reactions involved in cellular respiration of glucose

Answer 36

1. glycolysis - one glucose molecule is converted into two pyruvic acid molecules 2. formation of acetyl coA - transition step that prepares pyruvic acid the Krebs cycle 3. Krebs cycle - a series of reactions occurring in the mitochondrial matrix that involves the sequential conversion of one acid to another 4. electron transport chain - a series of electron carriers, ATP is produced via oxidative phosphorylation

Question 37

aerobic

Answer 37

with oxygen

Question 38

anaerobic

Answer 38

without oxygen

Question 39

how many ATP can glucose catabolism generate

Answer 39

30 or 32 ATP

Question 40

glycogen

Answer 40

a polysaccharide that is the only stored form of carbs in our bodies

Question 41

glycogenesis

Answer 41

the synthesis of glycogen

Question 42

glycogenolysis

Answer 42

the process of splitting glycogen into its glucose subunits

Question 43

gluconeogenesis

Answer 43

the process by which glucose is formed from non carbohydrate sources

Question 44

keto acids

Answer 44

amino acids that have been deaminated (their amino groups removed)

Question 45

lipolysis

Answer 45

the process of splitting glycerol and fatty acids

Question 46

glycerol

Answer 46

backbone of fate

Question 47

ketone bodies

Answer 47

molecules produced by the liver when the body is using fat for energy instead of glucose

Question 48

ketogenesis

Answer 48

the formation of acetoacetic acid, beta-hydroxybutyric acid, and acetone

Question 49

ketosis

Answer 49

when the concentration of ketone bodies in the blood rises above normal

Question 50

ketoacidosis

Answer 50

when too many ketone bodies accumulate and the blood pH falls

Question 51

lipogenesis

Answer 51

synthesis of lipids

Question 52

deamination

Answer 52

the process of removing an amino group from an amino acid

Question 53

ammonia

Answer 53

a highly toxic substance that is converted to urea by hepatocytes, released into the blood, and filtered by the kidneys, and then partially excreted into urine

Question 54

keto acid

Answer 54

remaining portion of amino acid after is has been deaminated

Question 55

transamination

Answer 55

the transfer of an amino group from an amino acid to pyruvic acid or to an acid in the Krebs cycle

Question 56

nutrients

Answer 56

chemical substances in food that body cells use for growth, maintenance, and repair

Question 57

minerals

Answer 57

inorganic elements that constitute about 4% of total body mass and are concentrated most heavily in the skeleton

Question 58

vitamins

Answer 58

organic nutrients required in small amounts to maintain growth and normal metabolism