Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biochem > Enzymes > Flashcards

Enzymes Flashcards

1
Q

proteins that catalyze the biochemical reactions

A

enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

enzymes catalyze reactions that ____________

A

break down food molecules to allow the cell to harvest energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

enzymes also catalyze the _________ reactions that produce the great variety of molecules required for __________.

A

biosynthetic

cellular life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Although there are thousands of enzymes, they all may be organized within ____ classes based on the ______

A

six

type of reaction they catalyze

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the 6 enzymes classes

A 
Oxidoreductases
Transferases
Hydrolases
Lyases
Isomerases
Ligases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

are enzymes that catalyze oxidation–reduction (redox) reactions.

A

Oxidoreductases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

is an oxidoreductase that removes hydrogen from a molecule of lactate.

A

Lactate dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Other subclasses of the oxidoreductases include

A

oxidases and reductases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

are enzymes that catalyze the transfer of functional groups from one molecule to another.

A

Transferases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

catalyzes the transfer of an amino functional group

A

transaminase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

catalyzes the transfer of a methyl group

A

transmethylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

catalyzes the transfer of a phosphoryl group.

A

kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

play a major role in energy-harvesting processes involving ATP

A

Kinases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

is an enzyme that catalyzes the transfer of a phosphoryl group from adenosine triphosphate (ATP) to a molecule of glucose in the first reaction of glycolysis

A

Hexokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Urease, a _____, catalyzes the reaction responsible for this smell of ___________

A

hydrolase

kitty litter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

______ catalyze hydrolysis reactions; that is, the addition of a water molecule to a bond, resulting in bond breakage.
These reactions are important in the ________

A

Hydrolases

digestive process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

_________, such as α-amylase, catalyze the hydrolysis of _______ bonds between __________ in a __________

A

glycosidases
glycosidic
monosaccharides
polysaccharide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

_______ catalyze the hydrolysis of _____ bonds in proteins to release _______

A

proteases
peptide
amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Lipases catalyze the _____ of the ester bonds in _________

A

hydrolysis

triglycerides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

catalyzes the transfer of a phosphoryl group.

A

kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

play a major role in energy-harvesting processes involving ATP

A

Kinases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

is an enzyme that catalyzes the transfer of a phosphoryl group from adenosine triphosphate (ATP) to a molecule of glucose in the first reaction of glycolysis

A

Hexokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Urease, a _____, catalyzes the reaction responsible for this smell of ___________

A

hydrolase

kitty litter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

______ catalyze hydrolysis reactions; that is, the addition of a water molecule to a bond, resulting in bond breakage.
These reactions are important in the ________

A

Hydrolases

digestive process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

_________, such as α-amylase, catalyze the hydrolysis of _______ bonds between __________ in a __________

A

glycosidases
glycosidic
monosaccharides
polysaccharide

26
Q

_______ catalyze the hydrolysis of _____ bonds in proteins to release _______

A

proteases
peptide
amino acids

27
Q

Lipases catalyze the _____ of the ester bonds in _________

A

hydrolysis

triglycerides

28
Q

_____is an example of a lyase. In the citric acid cycle, fumarase catalyzes the addition of a ____ molecule to the _______ of the substrate fumarate. The product is ____.

A

Fumarase
water
double bond
malate

29
Q

catalyzes a far more complicated reaction in which we see the removal of a group and formation of a double bond.

A

Citrate lyase

30
Q

citrate lyase catalyzes the removal of _____

A

an acetyl group from a molecule of citrate

31
Q

citrate lyase catalyzes the removal of an acetyl group from a molecule of citrate. The products of this reaction include

A

oxaloacetate
acetyl CoA
ADP
inorganic phosphate group (Pi)

32
Q

rearrange the functional groups within a molecule and catalyze the conversion of one isomer into another.

A

Isomerases

33
Q

converts one structural isomer, 3-phosphoglycerate, into another, 2-phosphoglycerate

A

phosphoglycerate mutase

34
Q

are enzymes that catalyze a reaction in which a C−C, C−S, C−O, or C−N bond is made or broken.

A

Ligases

35
Q

Ligases are enzymes that catalyze a reaction in which a C−C, C−S, C−O, or C−N bond is made or broken. This is accompanied by an

A

ATP-ADP interconversion

36
Q

DNA ligase catalyzes the joining of the ____ group of a nucleotide in a DNA strand with the _____ group of the adjacent nucleotide to form a ______ bond

A

hydroxyl
phosphoryl
phosphoester

37
Q

The common names for some enzymes are derived from the name of the ____, the reactant that binds to the enzyme and is converted into _____.

A

substrate

product

38
Q

In many cases, the name of the enzyme is simply derived by adding the suffix ___ to the name of the ___

A

-ase

substrate

39
Q

For instance, ____ catalyzes the hydrolysis of urea and ____ catalyzes the hydrolysis of the disaccharide lactose

A

urease

lactase

40
Q

______ catalyze the removal of hydrogen atoms from a substrate, while ______ catalyze the removal of carboxyl groups. Hydrogenases and carboxylases carry out the _____ reaction, adding hydrogen atoms or carboxyl groups to their _______-.

A

Dehydrogenases
decarboxylases
opposite
substrates

41
Q

the systematic name of the oxidoreductase lactate dehydrogenase is

A

lactate: NAD oxidoreductase.

42
Q

How does an enzyme speed up a chemical reaction?

A

It changes the path by which the reaction occurs, providing a lower energy route for the conversion of the substrate into the product, the substance that results from the enzyme-catalyzed reaction.

43
Q

in short words how do enzymes speed up chemical reactions

A

enzymes speed up reactions by lowering the activation energy of the reaction.

44
Q

Recall that every chemical reaction is characterized by an

A

equilibrium constant

45
Q

This equilibrium constant is actually a reflection of the difference in

A

energy between reactants and products

46
Q

This equilibrium constant is actually a reflection of the difference in energy between reactants and products that is, a measure of the

A

relative stabilities of the reactants and products.

47
Q

No matter how the chemical reaction occurs (which path it follows), the difference in energy between the reactants and the products is always the

A

same

48
Q

an enzyme cannot alter the ________ for the reaction that it catalyzes.

A

equilibrium constant

49
Q

an enzyme can really only provide a __________ for the conversion of reactant to product and, in this way, ____up the reaction

A

lower energy path

speed

50
Q

The rates of uncatalyzed chemical reactions often _____ every time the substrate concentration is doubled

A

double

51
Q

as long as the substrate concentration increases, there is a

A

direct increase in the rate of the reaction

52
Q

Although the rate of the reaction is initially responsive to the substrate concentration, at a certain concentration of substrate the rate of the reaction reaches a _________

A

maximum value.

53
Q

the rate of the reaction initially increases rapidly as the substrate concentration is _____ but that the rate levels off at a ____________

A

increased

maximum value

54
Q

At its _______, the active sites of all the enzyme molecules are occupied by a ________.

A

maximum rate

substrate molecule

55
Q

is the region of the enzyme that specifically binds the substrate and catalyzes the reaction.

A

The active site

56
Q

A new molecule of substrate ____ bind to the enzyme molecule until the substrate molecule already held in the active site is ________________

A

cannot

converted to product and released.

57
Q

For an enzyme-catalyzed reaction, the rate is at a maximum when all of the enzyme molecules are bound to the _____ Beyond this concentration of substrate, further increases in substrate concentration have __________ rate of the reaction.

A

subtrate

no effect on the

58
Q

From this information, we realize that an enzyme-catalyzed reaction must occur in two stages:

1) The formation of an _________ This binding of the substrate to the active site of the enzyme is a __________
2) Conversion of _____ into _____ and release of the ____ and ____. This step is ____ and ____ the rate of the overall reaction.

A 
enzyme-substrate complex
rapid step.
substrate
product
product 
enzyme
slower
limits
59
Q

Stage 2 of the enzyme catalyzed reaction is called the __________

A

rate-limiting step

60
Q

why is it stage of the enzyme catalyzed reaction called the rate-limiting step

A

because the rate of the reaction is controlled, or limited, by the speed with which the substrate is converted into product and is released.

61
Q

Ultimately, the reaction rate is dependent on the

A

amount of enzyme that is available.

Biochem (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions