Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology module 2 > 2.4 Enzymes > Flashcards

2.4 Enzymes Flashcards

(70 cards)

Start Studying
1
Q

What are enzymes

A

-proteins made inside cells in the ribosomes
-biological catalysts

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

What is the tertiary structure

A

the final shape of an enzyme which is determined by the sequence of amino acids

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

what are catalysts

A

substances which speed up biochemical reactions

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

what can enzymes be affected by

A

-Ph
-temperature

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

what is the turn over rate

A

how fast an enzyme works

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what can the active site and shape of substrate be described as

A

complementary

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

identify some examples of enzymes

A

-catalse
-amylase
-pepsin
-lipase
-maltase
-trypsin

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

where is catalase found and what does it do

A

in most living organisms that are exposed to oxygen
breaks down harmful hydrogen peroxide

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

what sort of enzyme is catalyse

A

intracellular

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

where is catalase found in eukaryotes

A

peroxisomes

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

what sort of reactions do enzymes catalyse

A

metabolic

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

identify some extracellular enzymes

A

amylase
trypsin

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

why may an enzyme not function

A

doesn’t have its amino acids in the correct order

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

why are enzymes specific

A

they all have differently shaped action sites

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

define extracellular

A

excreted onto substance

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

define intracellular

A

substrate acted upon inside cells

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

what is the enzyme product complex

A

enzyme molecule with product molecules in its action site

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

what is the enzyme-substrate complex

A

enzyme molecule with substrate molecules in its active site

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

what is the product of the enzyme substrate complex

A

smaller product molecules

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

what is the product of the enzyme product complex

A

one larger product molecule

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

what is the lock and key hypothesis

A

that the substrate fits perfectly into the enzyme

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

what is the induced fit hypothesis

A

the active site is still complementary to the substrate but its active site changes shape to mould around it

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

what does catabolic mean

A

breaks down molecules

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

what does anabolic mean

A

builds up molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what shape are enzymes
globular
26
what is hydrogen peroxide
a bi product of many metabolic reactions
27
what is the equation for the break down of hydrogen peroxide
hydrogen peroxide ----> water + oxygen +energy catalase
28
what is a limiting factor
factor which can alter the rate of a reaction if all other factors are kept constant
29
what happens if enzyme concentration increases
-more active sites are available -more successful collisions
30
what happens if an enzymes temperature increases
bonds break, tertiary structure unravels, the active site shape is lost and the enzyme denature
31
how does denaturation by heating happen
heating increases kinetic energy =more collisions molecules vibrate more so bonds break substrate is no longer complementary to active site
32
what are the properties of enzymes
-globular -soluble in water -3d tertiary structure -catalysts -specific
33
what is an inhibitor
a substance that reduces or stops a reaction
34
what is competitive inhibition
substances similar to the substrate which can occupy active sites without triggering reactions inhibiting enzyme activity
35
what is non-competitive inhibition
inhibitors that can block or change the shape of the active site of an enzyme by binding to the allosteric site
36
what is substrate inhibition
excess substrate which can compete for the active site, slowing the reaction speed
37
what is end product inhibition
after the catalysed reaction has reached completion, product molecules stay slightly bound to the enzyme. The enzyme cannot form more of the product than the cell needs
38
how are metabolic sequences controlled
the product of one enzyme becomes the substrate for the next enzyme catalysed reaction in the metabolic pathway
39
what happens when the product of the last enzyme catalysed reaction attaches to a part of the first enzyme in the pathway
this binding changes the shape of enzyme 1's active site, preventing the pathway from running
40
what is a buffer
something that resists changes in PH
41
what will you use buffer solutions for in lab investigations
to maintain desired PH for investigating enzyme action at different PH values or to keep the PH constant whilst investigating another factor
42
how do changes in PH affect bonds within molecules
excess hydrogen ions interfere with hydrogen bonds and ionic forces so the active site of the enzyme will change
43
how does increasing the concentration of hydrogen ions affect the active site
protons cluster around negatively charged groups this interferes with the binding
44
what happens if there is a small change in PH
active site is disrupted rate of reaction is slow
45
what happens if the optimum PH is restored
hydrogen bonds reform and the active site shape is restored
46
what happens at extremes of PH
enzymes denatures
47
what is the optimum Ph of intracellular enzymes
close to 7
48
what is the optimum PH of extracellular enzymes
they differ
49
what is an example of intracellular enzymes + PH
during digestion, amylase that digests starch to maltose works best at a PH of 6.8
50
what is an example of extracellular enzymes + PH
As food passes in your stomach, hydrochloric acid is secreted giving a low PH. Pepsin works best at values between 1 and 2.
51
what are coenzymes
organic molecules that bind to enzymes to help them function
52
what are the 3 types of cofactors
-prosthetic groups -ions -coenzymes
53
what is an example of a coenzyme
-NADP -Coenzyme A
54
are coenzymes organic
yes, organic vitamins
55
what is a coenzymes method of action
binds permanently/not permanently dependant if enzyme contains carbon
56
what is an example of an inorganic ion factor
chloride ion
57
what is the method of action of an inorganic ion factor
changes the charge distribution on the surface of the substrate molecule
58
what is an example of a prosthetic group
zinc
59
are prosthetic groups organic
no
60
what is the method of action of prosthetic groups
binds permanently to the active site
61
what is carbonic anhydrase
an enzyme that catalyses the reaction between CO2 and H2O to form carbonic acid in red blood cells which only functions when a prosthetic group is permanently attached
62
what are examples of poison inhibitors
-cyanide -snake venom
63
what does cyanide do
inhibits respiratory enzymes (cytochrome oxidase) and changes the shape of active site which stops respiration
64
what does cyanide affect
reactions requiring ATP are no longer supplied so there is no energy which causes cell failure
65
what does snake venom do
inhibits enzyme (acetylcholinesterase) used to degrade the neurotransmitter acetylcholine
66
what is the effect of snake venom
stops nerve impulses from being transmitted and stops muscle contraction- leads to flaccid paralysis
67
what are examples of medicinal inhibitors
-aspirin -protease
68
what does aspirin do
contains salicylic acid and binds to enzymes which catalase the formation of prostaglandins
69
what is the effect of aspirin
prevents the formation of prostaglandins which make nerves more sensitive to pain and swelling
70
what does protease do
stops protease cutting viral RNA into smaller pieces. The virus can't inject its RNA into a host cell to replicate

Biology module 2 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions