Chem 103 - Exam 2

Front 1

The purpose of coupling two biochemical reactions is to

Back 1

use an exergonic reaction to drive an endergonic reaction

Front 2

In a pair of coupled reactions, if the favorable reaction releases more energy than the amount required by the unfavorable reaction, the excess energy is

Back 2

released as heat and used to maintain body temperature

Front 3

Endergonic reactions are those that have a _ value of ΔG and _ spontaneous

Back 3

positive; non-spontaneous

Front 4

Which sequence illustrates the order of the steps from food to biochemically useful energy?

Back 4

digestion; acetyl-SCoA production; citric acid cycle; ATP production

Front 5

All of the following are energy strategies used in biochemical reactions except

Back 5

Chemical reactions occur in pairs in order to change the value of ΔG for one of the reactions

Front 6

ATP is the molecule most often used for energy transport because

Back 6

its hydrolysis releases an intermediate amount of energy and is relatively slow except in the presence of the appropriate enzymes

Front 7

Which statement is true concerning the relationship between FAD and FADH2?

Back 7

FADH2 is the reduced form of FAD

Front 8

In addition to producing ATP, the citric acid cycle produces _ as high energy molecules and _ as its major chemical waste product

Back 8

reduced coenzymes; CO2

Front 9

In the first step of the citric acid cycle, acetyl-SCoA reacts with _ to produce _ which is isomerized to _ in the second step

Back 9

oxaloacetate; citrate; isocitrate

Front 10

The mitochondria are the location where _ takes place and most _ is produced

Back 10

citric acid cycle; ATP

Front 11

The common molecule produced from all foods at the second stage of catabolism is

Back 11

acetyl-SCoA

Front 12

In a pair of couple reactions, if the favorable reaction releases more energy than the amount required by the unfavorable reaction, the excess energy is

Back 12

released as heat and used to maintain body temperature

Front 13

In steps 5-8 of the citric acid cycle, the high-energy molecules _, _, and _, are produced and _ is regenerated to begin another turn of the cycle

Back 13

GTP; FADH2; NADH/H+; oxaloacetate

Front 14

The ultimate source of energy for all but very few biochemical reactions is

Back 14

The sun

Front 15

The driving force which provides the energy for synthesis of ATP in the fourth stage of metabolism

Back 15

the concentration gradient of hydrogen ions between the two sides of the inner mitochondrial membrane

Front 16

The metal that acts as an electron carrier in the cytochromes in the electron transport is

Back 16

Iron

Front 17

ATP is the molecule most often used for energy transport because

Back 17

its hydrolysis releases an intermediate amount of energy and is relatively slow except in the presence of the appropriate enzymes

Front 18

Which statement is true concerning the relationship between FAD and FADH2?

Back 18

FADH2 is the reduced form of FAD

Front 19

The reaction in which ATP is converted to ADP with release of 7.3 kcal is a(an) _ reaction

Back 19

hydrolysis

Front 20

The fourth stage of metabolism, in which the high energy molecules from stage three are oxidized to produce ATP is referred to as

Back 20

the electron transport chain

Front 21

The energy released by GTP hydrolysis is (more than, less than or the same) as ATP hydrolysis

Back 21

the same

Front 22

In the TCA or citric acid cycle, α-Ketoglutaric acid reacts with co-enzyme A to yield

Back 22

succinyl-SCoA

Front 23

In the TCA or citric acid cycle, the reactions at steps 3, 4, 6 and 8 are catalyzed by

Back 23

NAD+ and FAD

Front 24

_ is the common intermediate of all food groups

Back 24

pyruvate?

Front 25

In the 1st stage of metabolism, the catabolic process is facilitated by _

Back 25

amylase

Front 26

The pH difference in the mitochondria is a result of the overall process of _

Back 26

metabolism

Front 27

The electron transport chain transfers electrons from _ co-enzymes to oxygen and is coupled to _ production

Back 27

reduced; ATP

Front 28

In addition to flavoproteins and the heme protein _, the respiratory chain of mitochondria includes the small molecules _

Back 28

cytochrome; ubiquinones

Front 29

Whereas digestion is _, metabolism is _

Back 29

catabolic; anabolic

Front 30

The citric acid cycle supplies the _ with _, which ultimately generate energy

Back 30

electron transport chain; reduced coenzymes

Front 31

A glycosidic bond is

Back 31

a bond formed between an anomeric carbon atom and any OR group

Front 32

The linkage joining the two monosaccharides in the dissacharide shown in the structure is a(n) _ glycosidic linkage

Back 32

β (1,4)

Front 33

Which is the best description of a carbohydrate?

Back 33

A compound that is composed of an aldehyde or ketone and has one or more hydroxyl groups

Front 34

Lactose when hydrolyzed will form

Back 34

glucose and galactose

Front 35

Cellulose is a polymer consisting of thousands of

Back 35

β-glucose molecules

Front 36

Which substance is a monosaccharide?

Back 36

cellulose

Front 37

_ is converted to ketone bodies during starvation, which can provide up to 50% of the ATP needed for homeostasis

Back 37

Acetyl-SCoA

Front 38

The metabolic process which produces glucose from _ sources is called _

Back 38

non-carbohydrate; gluconeogenesis

Front 39

In the 1st stage of carbohydrate metabolism the enzyme _ catabolizes _ and _, which are polymeric forms of the carbons that supply the TCA cycle

Back 39

α-amylase; starch; glycogen

Front 40

The blood clotting factor heparin, insect exoskeleton chitin and chondroitin found in the fluids of the eyes and joints are all synthesized from _

Back 40

monosaccharides

Front 41

Amylopection and glycogen both have _ and _ glycosidic bonds

Back 41

α-1,4; α-1,6

Front 42

Which is a hemiacetal?

Back 42

glucopyranose

Front 43

Lactate formed in muscles can be utilized through

Back 43

glucose-alanine cycle

Front 44

α-glycosidic bond is present in

Back 44

maltose, sucrose and lactose

Front 45

compounds having the same structural formula but differing in spatial configuration are known as _

Back 45

optical isomers

Front 46

In the 1st stage of carbohydrate metabolism the enzyme _ catabolizes _ and _, which is one source of the carbons that supplies the TCA cycle

Back 46

amylase; glucose; other sugars

Front 47

Sucrose is a disaccharide of _ and _, linked by a(n) _ bond

Back 47

glucose; fructose; ether glycosidic

Front 48

_ is the most abundant polysaccharide in nature

Back 48

Cellulose

Front 49

Two sugars which differ from one another only in configuration around the C1 carbon atom are termed _

Back 49

anomers

Front 50

The reducing ability of carbohydrates is due to _

Back 50

carboxyl group

Front 51

The formation of the stable, low energy ring structure in D-glucose requires that _ forms a hemiacetal

Back 51

c-1 and c-4

Front 52

Exergonic reaction picture

Back 52

Front 53

Endergonic reaction picture

Back 53

Front 54

ATP to ADP picture

Back 54

Front 55

Citric acid cycle picture

Back 55

Front 56

Electron transport chain process picture

Back 56

Front 57

Metabolism picture

Back 57

Front 58

Disaccharide pictures

Back 58