Biochem Exam 1

Front 1

what are the most abundant biomolecules in the human body

Back 1

water > proteins > triglycerides

Front 2

which of the following is a covalent bond:

H20

NaCl

CaCl2

KBr

Back 2

H20

Front 3

what kind of process is describe by: carbohydrate monomers undergoing dehydration/condensation synthesis?

Back 3

endergonic (bond formation)

Front 4

what are the energy rich bonds

Back 4

anhydrides and thioester

Front 5

what kind of process is described by hydrolysis of triglycerides to form glycerol and 3 fatty acids?

Back 5

exergonic (bond cleavage by hydrolysis)

Front 6

what is an isomer

Back 6

same molecular formula, different structural formula

Front 7

Structural Isomers

Back 7

same mol formula, atoms and functional groups arranged differently

different physical and chemical properties

Front 8

geometric isomers

Back 8

identical functional groups, differ in arrangement around rigid portion of molecules (cis and trans)

different physical and chemical properties

Front 9

Enantiomers

Back 9

aka optical isomers

identical functional groups, orientation of substituents around mirror image carbon varies

same physical and chemical properties

Front 10

positional isomers

Back 10

identical functional groups, position of these groups varies within the molecule

different physical and chemical properties

Front 11

properties of biomolecues are determined by their

Back 11

noncovalent interactions

Front 12

noncovalent binding is reversible or irreversible

Back 12

reversible

Front 13

hydrogen bonds

Back 13

H bonded to O > N >S

Front 14

electrostatic interaction

Back 14

formed between oppositely charged groups

Front 15

ion dipole interactions

Back 15

formed between charged group and polarized bonds

Front 16

hydrophobic interactions

Back 16

interface between a non polar structure and water is energetically unfavorable

force used to hold non polar structures together in an aqueous environment

Front 17

van der waals

Back 17

appear whenever two molecules approach each other

caused by induced dipoles in the molecules

Front 18

How many H bonds can water form?

Back 18

4

Front 19

where is Na+, Ca2+ and Cl- more prevalent

Back 19

extracellularly

Front 20

where is K+ more prevalent

Back 20

intracellularly

Front 21

pH

Back 21

-log[H+]

Front 22

bronsted acid

Back 22

releases proton

Front 23

bronsted base

Back 23

accepts proton

Front 24

most important acid groups

Back 24

carboxyl

phosphate ester

phosphodiester

(deprotonated at pH 7)

sulfhydryl

phenolic hydroxyl

(deprotonated well above pH 7)

Front 25

most important basic groups

Back 25

aliphatic amino

-primary, secondary, tertiary

guanidino (protonated at pH 7)

aromatic amines (protonated at pH above 7)

Front 26

Henderson Haselbach equation

Back 26

pH = pK - log [R-COOH]/[R-COO-]

= pK +log [R-COO-]/[R-COOH]

Front 27

D-glucose

Back 27

most important monosaccharide

6 carbon sugar

carbons ar numbered starting at the aldehyde carbon

each asymmetrical carbons can form optical isomers

Front 28

D-mannose and _____ are epimers

Back 28

D-glucose

Front 29

How are epimers and enantiomers different?

Back 29

epimers have different physical, chemical, and biological properties. One asymmetrical carbon

enantiomers: identical physical and chemical properties. All carbons are mirror images

Front 30

carbohydrate epimers

Back 30

monosaccharides with different orientation around one of their asymmetrical carbons

diastereomers

have different physical and chemical properties

Front 31

D- Mannose and D-Galactose are Epimers of

Back 31

D-Glucose

Front 32

Furanose

Back 32

monosaccharide whose ring contains five atoms

Front 33

pyranose

Back 33

monosaccharide whose ring contains six atoms

Front 34

True or false: an individual alpha D glucopyranose molecule CANNOT interconvert to Beta D glucopyranose

Back 34

False

Front 35

mutarotation

Back 35

anomie's can interconvert spontaneously

Front 36

glycosidic bonds

Back 36

combine monosaccharides into larger molecules

anomeric carbon forms the bond in either alpha or beta configuration, conformation is locked, and they no longer have mutarotation

Front 37

which of the following carb molecules does not have a reducing end?

lactose

maltose

glucose

sucrose

Back 37

sucrose

Front 38

o-glycosidic:

Back 38

sugar binds through an oxygen atom

Front 39

n-glycosidic

Back 39

sugar binds through a nitrogen atom

Front 40

what kind of glycosidic bonds does glycogen form?

Back 40

alpha 1-4 and alpha 1-6

Front 41

amylose

Back 41

alpha 1-4

Front 42

cellulose

Back 42

Beta 1-4

Front 43

glycogen

Back 43

alpha 1-4, and alpha1-6

Front 44

cation

Back 44

below pK of the carboxyl group

Front 45

anion

Back 45

above pK of the amino group

Front 46

zwitterion

Back 46

between pK of the carboxyl group and pK of amino group

Front 47

below pKa

Back 47

more protonated, less deprotonated

Front 48

at pKa

Back 48

half protonated, half deprotonated

Front 49

above pKa

Back 49

less protonated, more deprotonated

Front 50

isoelectric point

Back 50

pH value at which the numb rod positive charges equals the number of negative charges

pK is property of functional group

pI is property of entire molecule

Front 51

small amino acids

Back 51

glcyine and alanine

Front 52

branched chain amino acids

Back 52

valine

leucine

isoleucine

Front 53

hydroxyl amino acids

Back 53

serine

threonine

Front 54

sulfur amino acids

Back 54

cysteine

methionine

Front 55

aromatic amino acids

Back 55

phenylalanine

tyrosine

tryptophan

Front 56

acidic amino acids and their derivatives

Back 56

aspartate

asparagine

glutamate

glutamine

Front 57

basic amino acids

Back 57

lysine

arginine

histidine

Front 58

proline

Back 58

imino acid

Front 59

properties of peptide bond

Back 59

non-ionizable

forms hydrogen bonds

Front 60

solubility of proteins depends on

Back 60

pH and salt concentration

Front 61

most secreted proteins and membrane proteins have:

Back 61

disulfide bonds

Front 62

alpha helix is maintained by

Back 62

hydrogen bonds

Front 63

what amino acids can't be alpha helix

Back 63

proline is too rigid

glycine is too flexible

Front 64

beta pleated shees

Back 64

hydrogen bonds form side by side between the peptide bonds C=O and N=H

can be parallel or antiparallel

Front 65

tertiary structures

Back 65

within the same polypeptide chain

formed by hydrophobic interactions among amino acid side chains

Front 66

quaternary structures

Back 66

defined by the interactions between or among different polypeptides

subunits are held together by non covalent interactions or disulfide bonds

Front 67

disulfide bonds are apart of what protein structure

Back 67

primary

Front 68

globular protein

Back 68

have compact shapes

most are water soluble but have hydrophobic cores

ex: myoglobin, hemoglobin, enzymes, membrane proteins, plasma proteins

Front 69

fibrous proteins

Back 69

long and thread like

most serve structural functions

ex: keratin, collagen, elastin

Front 70

denaturation is reversible or irreversible

Back 70

irreversible

Front 71

heme group exists predominantly in what state

Back 71

ferrous state (Fe2+)

Front 72

effects of BPG

Back 72

decreases the oxygen binding affinity of Hgb - negative allosteric effector

concentration increases in hypoxic conditions at high elevations

Front 73

low pH =

Back 73

low O2 affinity to Hb

Front 74

high CO2 =

Back 74

low O2 affinity to Hb

Front 75

an acidic ph would cause what kind of shift on the oxygen dissociation curve?

Back 75

right shift

Front 76

methemoglobin

Back 76

nonfunctional oxidized form of hemoglobin

the oxidation of heme to the ferric form (Fe3+)

Front 77

carbon dioxide is mostly transported as

Back 77

bicarbonate dissolved in plasma

Front 78

when delta G is negative, the rxn is?

Back 78

exergonic and spontaneous

Front 79

first order reaction

Back 79

V = kx [A]

exponential graph

Front 80

Zero order reaction

Back 80

V= k

linear graph

Front 81

second order reaction

Back 81

V = k [A]x[B]

hyperbolic graph

Front 82

stereoselectivity

Back 82

a three point attachment is the minimal requirement for stereoselectivity

Front 83

Km =

Back 83

1/2 Vmax

Front 84

high Km =

Back 84

low affinity for substrate

Front 85

low Km =

Back 85

high affinity for substrate

Front 86

alcohol metabolism follows what order kinetics

Back 86

zero order

Front 87

enzyme activity depends on

Back 87

pH and temperature

Front 88

allosteric enzyme

Back 88

more than one active site and positive cooperatitvity between the active sites

Front 89

is allosteric binding reversible

Back 89

yest

Front 90

positive allosteric effectors

Back 90

activates... shift graph to the left - lower Km

Front 91

negative allosteric inhibitor

Back 91

inhibits... shifts graph to the right - higher Km

Front 92

competitive enzyme inhibitor

Back 92

two alternative substrates compete for the same enzyme

Vmax is same

Km reduced

Front 93

noncompetitive inhibitors

Back 93

structurally unrelated to the substrate

do not prevent substrate binding but block catalysis

vmax reduced

km stays the same

Front 94

uncompetitive inhibitors

Back 94

bind only to E-substrate complex, but not E

Vmax and Km reduced

works best high [S]

Front 95

irreversible inhibitors

Back 95

form covalent bond with the enzyme

can be overcome only by the synthesis of a new enzyme

Front 96

oxidoreductases

Back 96

catalyze REDOX

ex: dehydrogenases, oxygenases, and peroxidases

Front 97

transferases

Back 97

transfer a group from one molecule to another

ex: kinases, phosphorylases

Front 98

hydrolases

Back 98

cleave bonds by the addition of water

names indicate substrates or bonds they act on -

Front 99

lyases

Back 99

remove a group non hydrolytically

dehydratases, decarboxylases

opposite direction (creating bonds) - synthases

Front 100

isomerases

Back 100

interconvert positional, geometic, or optical siomers

Front 101

ligases

Back 101

couple the hydrolysis of a phosphoanhydride bond to the formation of a bond

synthetases,

Front 102

ATP

Back 102

a ribonucleotide (precursor for RNA synthesis)

serves as energetic currency

Front 103

exergonic reactions

Back 103

sythesize and release ATP

Front 104

endergonic reactions

Back 104

use ATp

Front 105

most important part of the ATP molecule

Back 105

the three phosphate residue

Front 106

magnesium is important in what

Back 106

stabilizing ATP

Front 107

phosphorylation

Back 107

covalent attachment of phosphate to a substrate

forming phosphate ester bond

ATP is the phosphate donor

Front 108

Cosubstrates NAD and NADP

Back 108

catalyze redox reactions (electron transfers)

Front 109

NAD+

Back 109

acquires 2 electrons and a proton -> NADH

feeds them into the mitochondria

reduces oxygen to water

NAD resides more in the mitochondria

Front 110

NADP+

Back 110

accepts electrons in catabolic pathways --> NADPH

feed them to biosynthetic pathways

to make reduced products

NADP/H resides more in cytoplasm

Front 111

coenzyme A

Back 111

soluble carrier of acyl groups

acetyl coA, fatty acyl coA

sulfhydryl group forms energy - rich thirster bonds

Front 112

S-Adenosyl Methionine (SAM)

Back 112

cosubstrate

donate methyl groups

methylation reaction converts SAM to SAH

Front 113

enzymes require alkali metals:

Back 113

Na+ and K+ to maintain active conformation

Front 114

transition metals ____, ___, ____, ____ are found in ____

Back 114

iron, zinc, copper, manganese are found in active site

act as lewis acids

ex: oxygenase reactions, anhydrase reactions

Front 115

plasma

Back 115

obtained by centrifugation in the presence of an anticoagulant

plasma is the remaining 50-60% of volume appearing as a clear yellowish fluid

Front 116

what are the most important anticoagulants

Back 116

heparin and vitamin K

Front 117

serum

Back 117

blood clotting induced before centrifugation (no anticoag)

has the same composition as plasma except for the absence of fibrinogen and some other clotting factors that are used up during clotting

Front 118

where are plasma proteins derived

Back 118

LIVER

he liver makes 25 g of plasma proteins daily

half of total protein synthesis is in the liver

Front 119

glycoproteins

Back 119

except albumin, are N-linked oligosacharides end with sialic acid

removed from circulation when their oligosacchride chains are worn down

Front 120

osmotic pressure

Back 120

pressure that must be applied to a more concentrated solution to prevent the flow of pure solvents (osmosis)

Front 121

hypertonic

Back 121

more concentrated solution outside the cell, so water moves out (cells shrinks)

Front 122

hypotonic

Back 122

more concentrated solution inside the cell, so water moves in (cell swells)

Front 123

colloid osmotic pressure

Back 123

plasma maintains colloid osmotic pressure

necessary to prevent edema

albumin is 60% total plasma protein, and gives 80% of osmotic pressure

edema: when albumin drops below 2g/dL

Front 124

acute phase reactants

Back 124

*C-reactive protein

Front 125

Antibodies consist of

Back 125

2 heavy chains

2 light chains

connected with disulfide bonds

Front 126

maltose

Back 126

glucose + glucose with alpha 1,4 glycosidic bonds

Front 127

cellobiose

Back 127

glucose + glucose with B 1,4

Front 128

lactose

Back 128

galactose + glucose with Beta 1, 4

Front 129

sucrose

Back 129

fructose + glucose with alpha, beta 1, 2