Pcb3023 Cell Biology

Front 1

What is the major site for ATP production in the eukaryotic cell?

Back 1

mitochondria

Front 2

Where does transcription occur in a eukaryotic cell?

Back 2

nucleus

Front 3

Which features of eukaryotic cells are believed to have originated from the engulfing of a prokaryotic cell?

Back 3

mitochondria and chloroplasts

Front 4

Which of the following IS NOT found in the nucleus?
A) DNA
B) RNA
C) Proteins
D) Nucleotides
E) All are found in the nucleus.

Back 4

All are found in the nucleus

Front 5

Which is NOT a function of a eukaryotic cell membrane (the membrane which surrounds the cell?
A) Transport of wastes and nutrients
B) Maintain gradients
C) Cell Motility
D) Cell-Cell Communication
E) Production of ATP energy

Back 5

Production of ATP energy

Front 6

Which of the following is NOT true about prokaryotes?
A) One type is bacteria
B) One type is archaea
C) Some can do photosynthesis
D) One type is yeast
E) Some can use oxygen to oxidize food molecules

Back 6

One type is yeast

Front 7

The Golgi _____.
A) Is involved in sorting proteins to various membrane-bound organelles
B) Receives proteins from the rough ER
C) Packages proteins that are to be secreted from the cell
D) Is a stack of membrane-bound flattened sacs
E) All of the above

Back 7

All of the above

Front 8

The major function of the rough endoplasmic reticulum is _____.
A) Generation of energy
B) Synthesis of cytosolic proteins
C) Cell motility
D) Generation of phospholipids
E) Synthesis of secreted and membrane-associated proteins

Back 8

Synthesis of secreted and membrane-associated proteins

Front 9

Which of the following does NOT pertain to the cytoskeleton?
A) Contains actin filaments, microtubules and intermediate filaments
B) Provides structure to the cytoplasm of the cell
C) It gives shape and strength to the cell
D) It is involved in cell movement.
E) It helps generate ATP in the cell

Back 9

It helps generate ATP in the cell

Front 10

The term "compartmentalization" refers to:
A) The presence of membrane-bound organelles in eukaryotic cells
B) The ability of eukaryotic cells to secrete proteins
C) The ability of eukaryotic cells to make contact with each other
D) The fact that eukaryotic cells produce energy
E) The ability of a eukaryotic cell to contain a prokaryotic cell

Back 10

The presence of membrane-bound organelles in eukaryotic cells

Front 11

The four groups that amino acids are classified into are _____.

Back 11

basic
acidic
uncharged polar
nonpolar

Front 12

The THREE amino acids that carry positive charges at neutral pH are _____.

Back 12

lysine
arginine
histidine

Front 13

Which of the following short proteins chains (or peptides) would be considered the most HYDROPHOBIC?
a) lysine-arginine-histidine-glycine-lysine
b) glutamic acid-glycine-aspartic acid-leucine-glutamic acid-aspartic acid
c) proline-leucine-valine-proline-alanine-methionine
d) cysteine-methionine-cysteine-valine-glutamic acid
e) None of the above.

Back 13

proline-leucine-valine-proline-alanine-methionine

Front 14

Which of the following amino acids would likely be found on the SURFACE of a folded protein?
a) Glutamic Acid
b) Proline
c) Glycine
d) Leucine
e) Alanine

Back 14

Glutamic acid

Front 15

An acidic, basic, or uncharged polar amino acid would likely be found here in a folded protein.

Back 15

On the surface

Front 16

The nonpolar amino acids are would be found here in the folded protein.

Back 16

In the inside of the folded protein, away from the aqueous cytoplasm.

Front 17

The nonpolar amino acids are found in the inside of the folded protein, because they are:

Back 17

hydrophobic and are kept away from the aqueous cytoplasm

Front 18

Which of the following amino acids contain a sulfur atom?
a) Tryptophan
b) Cysteine
c) Methionine
d) Arginine
e) more than one of the above

Back 18

more than one of the above

Front 19

What would be the NET charge of the following peptide in a neutral buffer (pH = 7.4)? ARG-LYS-ARG-GLU-LYS-LYS-GLY-VAL.
a) +4
b) −4
c) +2
d) −2
e) 0

Back 19

+4

Front 20

If a protein contained the sequence: glutamic acid-glycine-aspartic acid–leucine-glutamic acid-aspartic acid, which of the amino acid chains below would it most likely form ionic bonds with?
a) lysine-arginine-histidine-glycine-lysine
b) glutamic acid-glycine-aspartic acid-leucine-glutamic acid-aspartic acid
c) proline-leucine-valine-proline-alanine-methionine
d) cysteine-methionine-cysteine-valine-glutamic acid
e) None of the above

Back 20

lysine-arginine-histidine-glycine-lysine

Front 21

According to lecture, the macromolecules found in a cell are all _____.

Back 21

polymers

Front 22

Phospholipid molecules in water might be expected to stick to one another by virtue of _____ interactions occurring between their tails.

Back 22

hydrophobic

Front 23

Remember that hydrogen atoms forming nonpolar covalent bonds (for example, with C) are NOT ideal for:

Back 23

hydrogen bonding

Front 24

Remember that hydrogen atoms forming _______ (for example, with C) are NOT ideal for hydrogen bonding.

Back 24

nonpolar covalent bonds

Front 25

Which of the following can be used by cells to produce ATP energy?
a) sugars
b) fatty acids
c) amino acids
d) sugars and fatty acids
e) sugars, fatty acids, and amino acids

Back 25

All of them

Front 26

How many elements are found in nature?

Back 26

92

Front 27

These elements make up 98% of all elements in a cell

Back 27

C, H, O

Front 28

What is the most abundant substance in cells?

Back 28

Water, makes up 70% of the cell

Front 29

Hydrophilic molecules have a _____ charge.

Back 29

partial or full plus or minus charge. they are polar

Front 30

Hydrophilic molecules are polar or non-polar?

Back 30

polar

Front 31

Hydrogen bonding is formed by hydrophilic or hydrophobic molecules?

Back 31

hydrophilic

Front 32

Hydrophobic molecules have a _____ charge.

Back 32

neutral. they are non-polar

Front 33

Hydrophilic molecules form hydrogen bonds: T/F

Back 33

T

Front 34

Hydrophobic molecules form hydrogen bonds: T/F

Back 34

F

Front 35

These increase the level of H+

Back 35

acids

Front 36

These decrease the level of H+

Back 36

bases

Front 37

Acids increase the level of ___

Back 37

H+

Front 38

Bases decrease the level of ___

Back 38

H+

Front 39

Bases decrease the level of H+ by:

Back 39

direct: acquriing H+
indirect: release of OH-

Front 40

This is an important cellular base which forms NH3+ and OH-

Back 40

NH2

Front 41

Cells contain these 4 major building blocks of small organic molecules which makeup these larger units:

Back 41

Monosaccharides --> Polysaccharides
Fatty Acids --> Fats, Lipids, Membranes
Amino Acids --> Proteins
Nucleotides --> Nucleic Acids

Front 42

The four building blocks of the cell have different fates inside the cells; the overall distribution is toward formation of:

Back 42

large macromolecules

Front 43

The four building blocks of the cell have different fates inside the cells; the overall distribution is toward formation of large macromolecules. This is known as:

Back 43

polymer chemistry

Front 44

The formula for monosaccharides is:

Back 44

(CH2O)n
n= 3-7

Front 45

Monosaccharides form polysaccharides by covalent linkages through:

Back 45

-OH

Front 46

Monosaccharides undergo this type of reaction to form polysaccharides:

Back 46

condensation (dehydration)
(water expelled)

Front 47

Polysaccharides undergo this type of reaction to form monosaccharides:

Back 47

hydrolysis
(water consumed)

Front 48

These are the functions of sugars:

Back 48

-production of storage and energy
-cell walls (cellulose)
-extracellular matrix
-DNA/RNA
-linked to protiens

Front 49

Fatty acids have two chemically distinct regions:

Back 49

long hydrocarbon chain - hydrophobic
carboxyl head group - hydrophilic

Front 50

Three fatty acid chains linked to glycerol is known as:

Back 50

Triacylglycerols

Front 51

Two fatty acid chains linked to glycerol/PO4/head group is known as:

Back 51

Phospholipids

Front 52

Triacylglycerols are made up of:

Back 52

3 fatty acid chains linked to glycerol

Front 53

Phospholipids are made up of:

Back 53

2 fatty acid chains linked to glycerol/PO4/head group

Front 54

Fatty acids are stored as ________ through an ester linkage to glycerol to form triacylglycerols.

Back 54

an energy reserve

Front 55

Phospholipids are the major constituents of:

Back 55

cell membranes

Front 56

These are the functions of fats:

Back 56

-production and storage of energy
-cell membranes
-cell signaling (steroids, signal transduction)

Front 57

Fats provide _______ than sugars by weight.

Back 57

2x more energy

Front 58

Monosaccharides make covalent linkages through -OH groups to form:

Back 58

polysaccharides

Front 59

Amino acids are made up of:

Back 59

-Carboxylic acid group
-Amino group
-Side chain (R)
-Alpha Carbon

Front 60

What is this molecule?

Back 60

Amino Acid

Front 61

Name these parts of the amino acid:

Back 61

1) Amino group
2) Side-chain group
3) Carboxyl group
4) Alpha Carbon

Front 62

Both the amino and carboxyl groups are ionized in an amino acid at this pH:

Back 62

7

Front 63

At pH 7 both the amino and carboxyl groups of an amino acid are:

Back 63

ionized

Front 64

At pH 7, an amino acid will ionize leaving the molecule charged in this way:

Back 64

amino group becomes NH3+
carboxyl group becomes COO-

Front 65

How does an amino acid look at pH 7?

Back 65

Front 66

Name the parts of the amino acid.

Back 66

1) Amino group
2) Side chain
3) Carboxyl group

Front 67

There are ____ distinct amino acids

Back 67

20

Front 68

This part of the amino acid confers its functionality (nonpolar, uncharged-polar, acidic, basic)

Back 68

Side chain

Front 69

Only this form of amino acid is used:

Back 69

L form

Front 70

Amino acids are linked via:

Back 70

peptide bonds

Front 71

These are the functions of proteins:

Back 71

Generation of proteins
Production of energy

Front 72

Nucleotides are made up of:

Back 72

-Nitrogen rings (pyrimidines, purines)
-Sugar (ribose or deoxyribose)
-Phosphate group (1, 2 or 3)

Front 73

These are the types of Nitrogen Rings:

Back 73

Purines (A, G)
Pyrimidines (T, U, C)

Front 74

These are the functions of nucleotides:

Back 74

DNA (A, G, C, T)
RNA (A, G, C, U)
Carriers of chemical energy (mainly ATP)
Signal molecules
Coenzymes

Front 75

All macromolecules are made with the same basic chemical reaction:

Back 75

dehydration (condensation)

Front 76

For a protein of 200 amino acids, there is this many possible sequences:

Back 76

20^200

Front 77

This specifies the shape of a macromolecule:

Back 77

noncovalent bonds

Front 78

These types of bonding specify the shape of a macromolecule:

Back 78

Van der Waals
Hydrogen
Hydrophobic
Ionic

Front 79

At very short distances, any two atoms show a weak interaction due to fluctuations in charges. This is known as:

Back 79

Van der Waals Forces

Front 80

Describe Van der Waals forces:

Back 80

At very short distances, any two atoms show a weak interaction due to fluctuations in charges

Front 81

A bond where a hydrogen is sandwiched between two electron-attracting ions. This is known as:

Back 81

Hydrogen bond

Front 82

Describe hydrogen bonding:

Back 82

A bond where a hydrogen is sandwiched between two electron-attracting ions

Front 83

Hydrogen bonding is ____ the strength of a covalent bond.

Back 83

1/20th

Front 84

Hydrophobic groups are forced together to minimize their disruption of hydrogen bonds in water. This is known as:

Back 84

Hydrophobic interactions

Front 85

Describe Hydrophobic interaction:

Back 85

Hydrophobic groups are forced together to minimize their disruption of hydrogen bonds in water

Front 86

The transfer of electrons to create a bond occurring between fully charged or partially charged groups.

Back 86

Ionic bonding

Front 87

When considered individually, _____ are very weak, but multiple bonds result in a very strong interaction, between different parts of the molecule.

Back 87

non-covalent bonds

Front 88

_____ bonds allow intermolecular interactions.

Back 88

Non-covalent

Front 89

_____ bonds allow the assembly of multiple macromolecules into a single structure.

Back 89

Non-covalent

Front 90

The assembly of multiple macromolecules into a single structure through non-covalent bonds is called:

Back 90

macromolecular assembly

Front 91

Macromolecules are made by these kinds of bonds:

Back 91

covalent

Front 92

3-D structure of macromolecules is formed through:

Back 92

non-covalent bonds

Front 93

The pH of a cell is:

Back 93

7.4

Front 94

Hydrogen bonds are the strongest when:

Back 94

the three atoms involved are in a straight line

Front 95

The second law of thermodynamics states that:

Back 95

In any system the degree of disorder (entropy) will increase over time.

Front 96

How do cells generate order?

Back 96

-There is a constant input of energy into the system.
-Cells release heat to their surroundings, increasing entropy in the environment.

Front 97

Cells release ____ to their surroundings, _____ entropy in the environment and _____ entropy in the cell.

Back 97

heat
increasing
decreasing

Front 98

The integrated network of chemical reactions that regulate life:

Back 98

metabolism

Front 99

Metabolism is:

Back 99

the integrated network of chemical reactions that regulate life

Front 100

This part of metabolism involves the breakdown of molecules and typically releases energy

Back 100

catabolism

Front 101

This part of metabolism involves the building or biosynthesis of molecules and typically requires energy

Back 101

anabolism

Front 102

An initial compound in a reaction which binds to an enzyme is known as:

Back 102

substrate

Front 103

A compound generated from the substrate which will likely become substrate itself for a new reaction.

Back 103

product

Front 104

Intrinsic energy within a compound, expressed in terms of calories (kcal)

Back 104

Free Energy (G)

Front 105

Free Energy is defined as:

Back 105

intrinsic energy within a compound, expressed in terms of calories (kcal)

Front 106

If ∆G is negative, the reaction will:

Back 106

proceed spontaneously
A --> B

Front 107

If ∆G is positive, the reaction will:

Back 107

not be spontaneous
A <-- B

Front 108

If ∆G is zero, the reaction will:

Back 108

be at equilibrium
A <==> B

Front 109

The amount of energy generated by

A <==> B

is equal to:

Back 109

∆G = G_B - G_A

Front 110

This means that the number of A molecules being converted to B is the same as B to A

Back 110

equilibrium

Front 111

Equilibrium means that there is the same number of A molecules and B molecules. T/F

Back 111

F

Front 112

Equilibrium is defined as:

Back 112

A reaction that the number of A molecules being converted to B is the same as B to A

Front 113

This is independent of the pathway of the reaction, and tells us nothing about the rate.

Back 113

∆G

Front 114

∆G is independent of the pathway of the reaction and tells us nothing about the rate. T/F

Back 114

T

Front 115

This can be used to predict the direction a reaction goes to

Back 115

∆G

Front 116

This can be used to find how much energy will be liberated or used in a reaction:

Back 116

∆G

Front 117

∆G can be used to predict:

Back 117

The direction a reaction goes (spontaneous or not)

How much energy will be liberated or used.

Front 118

∆G° + 0.616 kcal/mol • ln [B]/[A] = ?

Back 118

∆G

Front 119

∆G° represents:
∆G represents:

Back 119

standard free energy change (in test tube)

change in free energy (in cell)

Front 120

We can relate ∆G of biological systems to the relative SUBSTRATE and PRODUCT concentrations by doing this:

Back 120

Mix equal amounts of A and B in a test tube under STANDARD STATE CONDITIONS, and let it go to equilibrium.

Then, evaluate the concentrations of A and B.

Front 121

K_eq is defined as:

Back 121

the equilibrium constant, the value of [B]/[A] at equilbrium

[B] = concentration of product
[A] = concentration of substrate

Front 122

Enzymes provide:

Back 122

catalytic power

Front 123

Enzymes accelerate reactions by ______ times or more

Back 123

1,000,000

Front 124

Enzymes decrease the ______ required for reactions to occur.

Back 124

activation energy

Front 125

Enzymes decrease the activation energy by:

Back 125

bringing the substrate into a favorable conformation

Front 126

Enzymes do not affect the equilibrium, they accelerate the attainment of equilibrium. T/F

Back 126

T

Front 127

∆Go is known as:

Back 127

the free energy under standard state in the test tube

Front 128

Define the purpose, approach, equation, and variables with regards to free energy in the test tube.

Back 128

Purpose: to solve for G°
Approach: reaction GOES TO equilibrium
Equation: ∆G° = −0.616 kcal/mol (ln Keq)
Variables: ∆G° and Keq

Front 129

Define the purpose, approach, equation, and variables with regards to free energy in the cell.

Back 129

Purpose: to solve for G
Approach: reaction goes TOWARD equilibrium
Equation: ∆G = ∆G° + 0.616 kcal/mol • ln [B]/[A]
Variables: ∆G, ∆G°, and [B]/[A] (not Keq)

Front 130

In biological systems a chemical reaction that is not at equilibrium is capable of providing energy as it attains equilibrium state. This is known as:

Back 130

coupling

Front 131

Coupling is defined as:

Back 131

In biological systems a chemical reaction that is not at equilibrium is capable of providing energy as it attains equilibrium state.

Front 132

We collect free energy (∆G) in two basic forms:

Back 132

electrons (e−)‏
High energy phosphate (–PO4 2−)

Front 133

The overall free energy change for chemically coupled reactions (serial or independent rxns) is equal to:

Back 133

the SUM of the free energy changes of the individual steps.

∆Gs are ADDITIVE!

Front 134

How do reactions proceed in a timeframe that allows organisms to thrive?

Back 134

enzymes

Front 135

How do we collect the free energy from chemical reactions?

Back 135

oxidation

Front 136

This is an example of what kind of reaction?
C6H12O6 + O2 → H2O + CO2

Back 136

oxidation

Front 137

The oxidation of these fuel molecules generates the free energy to drive reactions:

Back 137

glucose, fatty acids, amino acids

Front 138

The oxidation of glucose, fatty acids, and amino acids generates:

Back 138

the free energy to drive reactions

Front 139

Glucose, fatty acids, and amino acids undergo this type of reaction to generate the free energy to drive reactions:

Back 139

oxidation

Front 140

Oxidation is the elimination of:

Back 140

H- (electrons)
H+

Front 141

The elimination of electrons is known as:

Back 141

oxidation

Front 142

Free energy is represented by:

Back 142

chemical bonds (electron pairs)

Front 143

These are the 'currency' of oxidation:

Back 143

electrons

Front 144

These serve as electron carriers:

Back 144

NAD+
FAD
NADP+

Front 145

These transfer electrons to the oxidative phosphorylation enzymes in the mitochondria:

Back 145

NAD+
FAD

Front 146

NAD+ and FAD transfer electrons to the:

Back 146

oxidative phosphorylation enzymes in the mitochondria

Front 147

The energy in the electrons is used to produce a H+ gradient, so that:

Back 147

ATP can be synthesized

Front 148

The energy in the electrons is used to produce a ______, so that ATP can be synthesized

Back 148

H+ gradient

Front 149

These amino acids have basic side chains:

Back 149

lysine
arginine
histidine

Front 150

These amino acids have acidic side chains:

Back 150

aspartic acid
glutamic acid

Front 151

Amino acids are commonly joined together by an amide linkage, called a:

Back 151

peptide bond

Front 152

These amino acids have uncharged polar side chains:

Back 152

asparagine
glutamine
serine
threonine
tyrosine

Front 153

These amino acids have nonpolar side chains:

Back 153

alanine
valine
leucine
isoleucine
proline
phenylalanine
methionine
tryptophan
glycine
cysteine

Front 154

Name this amino acid.

Back 154

glycine

Front 155

Name this amino acid.

Back 155

alanine

Front 156

Name this amino acid.

Back 156

valine

Front 157

Name this amino acid.

Back 157

arginine

Front 158

Name this amino acid.

Back 158

histidine

Front 159

Name this amino acid.

Back 159

aspartate

Front 160

Name this amino acid.

Back 160

glutamate

Front 161

Name this amino acid.

Back 161

serine

Front 162

Name this amino acid.

Back 162

threonine

Front 163

Name this amino acid.

Back 163

cysteine

Front 164

Name this amino acid.

Back 164

proline

Front 165

Name this amino acid.

Back 165

asparagine

Front 166

Name this amino acid.

Back 166

glutamine

Front 167

Name this amino acid.

Back 167

lysine

Front 168

Name this amino acid.

Back 168

tryptophan

Front 169

Name this amino acid.

Back 169

tyrosine

Front 170

Name this amino acid.

Back 170

phenylalanine

Front 171

Name this amino acid.

Back 171

isoleucine

Front 172

Name this amino acid.

Back 172

methionine

Front 173

Name this amino acid.

Back 173

leucine

Front 174

Only this form of amino acid is found in proteins:

Back 174

L-form

Front 175

Only the D form of amino acids are found in proteins: T/F

Back 175

F

Front 176

Only the L form of amino acids are found in proteins: T/F

Back 176

T

Front 177

This is the major electron donor in reductive biosynthesis and photosynthesis:

Back 177

NADPH

Front 178

The free energy of electrons is used to generate:

Back 178

ATP

Front 179

The universal currency of free energy in biological systems:

Back 179

ATP

Front 180

What is the basis of ATP's free energy?

Back 180

Electrostatic repulsion between the negative charges of −PO4 2−

Resonance stabilization

Front 181

The hydrolysis of ATP changes the ____ by a very large number, allowing thermodynamically unfavorable reactions to occur.

Back 181

Keq

Front 182

The hydrolysis of _____ changes the Keq by a very large number, allowing thermodynamically unfavorable reactions to occur.

Back 182

ATP

Front 183

The hydrolysis of ATP changes the Keq by a very large number, allowing:

Back 183

thermodynamically unfavorable reactions to occur.

Front 184

List some important compounds with high phosphoryl transfer potential:

Back 184

Phosphenolpyruvate (PEP) ∆Go −14.3
Creatine Phosphate ∆Go −10.3
ATP ∆Go −7.3
Glucose-1-phosphate ∆Go −5.3
Glucose-6-phosphate ∆Go −3.3

Front 185

Small molecules which bring unique chemical functionality to certain enzyme reactions.

Back 185

coenzyme

Front 186

This is the universal carrier of acyl groups:

Back 186

Coenzyme A (CoA)

Front 187

This is the reactive site of Acetyl Coenzyme A:

Back 187

terminal sulfhydral group

Front 188

The reduced form of NADP+ is:

Back 188

NADPH

Front 189

The oxidized form of NADPH is:

Back 189

NADP+

Front 190

The primary structure of a protein consists of:

Back 190

the amino acid sequence

Front 191

Once this is established, the protein will FOLD into a single conformation with the lowest energy state.

Back 191

primary structure

Front 192

Once a primary structure is established, the protein will FOLD into a single conformation with the lowest energy state. This is mediated by:

Back 192

non-covalent bonds

Front 193

Once a primary structure is established, the protein will FOLD into a single conformation with:

Back 193

the lowest energy state.

Front 194

The secondary structure of a protein consists of:

Back 194

STRETCHES of amino acids that fold into functional structures, based on the sequence of amino acids (primary structure)

Front 195

The secondary structure of a protein consists of stretches of amino acids that fold into functional structures, based on:

Back 195

the sequence of amino acids (primary structure)

Front 196

A protein's secondary structure can have these formations:

Back 196

Alpha Helix
SINGLE REGION of amino acids
Turns every ~ 4 amino acids

Beta Sheet
MULTIPLE REGIONS
Antiparallel OR Parallel

Front 197

The non-covalent bonds involved in the secondary structure of a protein are:

Back 197

hydrogen bonds

Front 198

In the secondary structure of a protein, alpha helices and beta sheets arise through:

Back 198

H-bonds between N-H and C=O groups in peptide backbone.

Front 199

Side chains of amino acids are involved in the hydrogen bonds which form alpha helices and beta sheets in the secondary structure of proteins. T/F

Back 199

F

Front 200

Protein secondary structure helices are important because they:

Back 200

Form membrane-spanning regions

Coiled-coils

Provide functional domains to many proteins

Front 201

Any part of a polypeptide chain that can fold independently into a compact, stable structure:

Back 201

functional domain

Front 202

These are examples of protein functionality:

Back 202

Protein-Protein Interaction
Protein-DNA Interaction
Substrate-Binding Site

Front 203

The tertiary structure of a protein consists of:

Back 203

The 3-D structure of the functional protein molecule (Conformation)

Involves all non-covalent bonding
(ionic, hydrogen, van der Walls, hydrophobic)

Front 204

Each protein normally folds into a single conformation with the lowest energy state but changes in shape can be caused by:

Back 204

binding of additional molecules
environmental changes
phosphorylation
other modifications

Front 205

Define Allosteric Protein

Back 205

a protein that has multiple conformations

Front 206

A protein that has multiple conformations. Generally, one form is active and the other form is inactive

Back 206

allosteric protein

Front 207

Many functional proteins often have more than one polypeptide chain. Each of these are called:

Back 207

subunit

Front 208

The quaternary structure of a protein consists of:

Back 208

A combination of MORE THAN ONE
independent polypeptide chains

Involves all non-covalent bonding detailed previously. (ionic, hydrogen, van der Walls, hydrophobic).

Front 209

Individual protein subunits can make these formations:

Back 209

filaments
sheets
spheres

Front 210

The majority of bonds that influence protein folding and structure are:

Back 210

non-covalent

Front 211

Disulfide bonds can influence protein structure. T/F

Back 211

T

Front 212

Non-covalent bonds are the only that influence protein folding and structure: T/F

Back 212

F

Front 213

Protein folding and structure is influenced by:

Back 213

non-covalent bonds
disulfide bonds

Front 214

List the structures of protein and the bonds that influence them.

Back 214

Primary
covalent
Secondary
Non-covalent
Tertiary
Non covalent and SH (covalent)
Quaternary
Non covalent and SH (covalent)

Front 215

Ligand binding occurs through this kind of bond:

Back 215

non-covalent

Front 216

An enzyme can increase the rate of a reaction in these ways:

Back 216

1) Brings TWO substrates together in a precise orientation.

2) Realignment of charges within substrate.

3) Physical stress of substrate to generate more favorable state.

Front 217

If KM is SMALL Number:

Back 217

Then it takes low level of [S] to fill the active site, and the ES complex is STRONG.

Front 218

If KM is LARGE Number:

Back 218

Then it takes high level of [S] to fill active sites, and the ES complex is WEAK.

Front 219

K_M is analogous to:

Back 219

Affinity

Front 220

Allows comparison of enzymes and
prediction of enzyme kinetics, based on cellular concentrations of substrates

Back 220

K_M

Front 221

When a compound binds to the active site and displaces or outcompetes the ligand for binding:

Back 221

COMPETITIVE enzyme inhibition

Front 222

When the enzyme is modified at a site different from the active site, to reduce the function of the enzyme.

Back 222

NON-COMPETITIVE enzyme inhibition

Front 223

This inhibition cannot be overcome by the addition of more ligand:

Back 223

NON-COMPETITIVE enzyme inhibition

Front 224

Non-competitive inhibition can be overcome by the addition of more ligand. T/F

Back 224

F

Front 225

Competitive inhibition causes this in Vmax and K_M:

Back 225

Vmax same
K_M changes

Front 226

Non-competitive inhibition causes this in Vmax and K_M:

Back 226

Vmax changes
K_M same

Front 227

The most common method of enzyme regulation involves feedback: T/F

Back 227

T

Front 228

Most common method of enzyme regulation. Usually involves control by amount of product formed. Reduces activity of enzymes in the pathway.

Back 228

feedback inhibition

Front 229

In a positive feedback loop this occurs:

Back 229

Usually, product feeds back to increase its own production

Front 230

In positive regulation this occurs:

Back 230

Increased activity through binding by ligand.

Front 231

How is enzyme activity changed?

Back 231

allosteric changes
change in conformation due to covalent modification or binding of ligand

Front 232

The addition or removal of phosphoryl groups (PO4) from a protein is the most common modification used to affect protein function: T/F

Back 232

T

Front 233

The addition or removal of _______ from a protein is the most common modification used to affect protein function

Back 233

phosphoryl groups (PO4)

Front 234

Catalyzes addition of PO4 to serine/threonine/tyrosine

Back 234

kinase

Front 235

Removes PO4 moiety

Back 235

phosphatase

Front 236

This is the most important chemical modification in cells.

Back 236

Phosphorylation / dephosphorylation

Front 237

What is the difference between fibrous and globular proteins?

Back 237

These are the quaternary shapes formed by proteins. Globular are spherical and soluble. Fibrous long filaments and insoluble.