Lesson 5 : Enzyme

Question 1

_________ are substances that speed up chemical reactions.

Answer 1

Catalysts

Question 2

Differentiate Anabolic and Catabolic

Answer 2

Anabolic - Building large molecules from small ones

Catabolic - Breaking down large molecules into small ones

Question 3

We call these substances that are built up or broken down as __________.

Answer 3

Substrates

Question 4

Enzymes are also ______________ in the chemical reactions they speed up.

Answer 4

highly specific

Question 5

What does amylase do

Answer 5

The enzyme Amylase breaks down Carbohydrate Starch (Polysaccharides) into Monosaccharides

Question 6

Glucose and Fructose can __________to form __________, and Sucrose can be broken down into Glucose and Fructose.

Answer 6

condense
Sucrose

Question 7

How do Enzymes Speed up Chemical Reactions?

Answer 7

Enzymes speed up reactions by lowering the Activation Energy.

Question 8

What is Activation Energy

Answer 8

Activation Energy is the amount of energy needed to start a reaction.

Question 9

How do Enzymes Work

Answer 9

Enzymes bind to their substrates, causing a chemical reaction to be catalyzed.

Question 10

Enzymes are ___________ that _____________ chemical reactions

Answer 10

proteins
catalyzes

Question 11

What is an Active Site

Answer 11

This is the specific place in the enzyme where substrates bind to.

This has a specific size, shape and chemical behavior rendered by the specific arrangement of its amino acids.

Every type of enzyme has a unique active site, which is why enzymes are specific to particular substrate only.

Question 11

What is the non-protein part of an enzyme

Answer 11

cofactor

Question 12

Examples of Enzymes

Answer 12

Protease - Breaks down proteins into amino acids

Carbohydrase - Breaks down carbohydrates into monosaccharides

Lipase - Breaks down lipids into fatty acids and glycerol

Catalase - Breaks down Hydrogen Peroxide into Carbon Dioxide and Water

Question 13

Kinds of Cofactors

Answer 13

Cations - Positively charged metal ions, bound temporarily to the active site to “activate” the enzyme.

Organic Molecules - Vitamins or vitamin products (coenzymes), that join enzyme-substrate complex temporarily.

If the cofactor is an organic molecule, then it is referred to as coenzyme.

Prosthetic Groups - Permanently bound to enzymes

Question 14

What are substrates

Answer 14

molecules that bind to enzymes.

Question 15

Differentiate the Models of an Enzyme Action

• Lock and Key Hypothesis
• Induced Fit Hypothesis

Answer 15

• Lock and Key Hypothesis : The substrate simply fits into the active site to form a reaction just like the key fits in its specific lock
• Induced Fit Hypothesis : In this model, the enzyme, upon binding of substrate, changes shape.

Question 16

The suitable temperature for enzymes to function properly is

Answer 16

37°C

Question 17

__________ in pH can affect these amino acids making it hard for substrates to bind.

Answer 17

Fluctuation

Question 18

Increasing enzyme concentration will __________ the ______ of reaction, as more enzymes will be ________ to bind with substrates.

Answer 18

increase
rate
available

Question 19

Increasing substrate concentration increases the rate of reaction because more substrate molecules will be _________ with enzyme molecules, so more product will be formed.

Answer 19

colliding

Question 20

Enzyme Inhibitors ________ or _________ the activity of enzymes in biochemical reactions. They either block or distort the active site, thus inhibiting the reaction.

Answer 20

reduce
stop

Question 21

Differentiate Competitive Inhibitors and Non Competitive Inhibitors

Answer 21

• Competitive Inhibitors : Occupy the active site and prevent a substrate molecule from binding to the enzyme.
• Non Competitive Inhibitors : Attach to parts of the enzyme, other than the active site, to distort the shape of an enzyme.

Question 22

What are the Nomenclature of Enzymes

Answer 22

Urease
The suffix -ase identifies a substance as an enzyme
Infrequently, substrate only is specified in the name but not the reaction type.

Trypsin
The suffix - in is still being used in some of the first studied digestive enzymes

Oxidase
The type of reaction catalyzed by the enzyme is usually noted in the prefix

Glucose Oxidase
The identity of the substrate is usually included

Question 23

Enzymes bind to ________ which they either ____________ or _____________

Answer 23

substrates
break down
condense

Question 24

Enzymes may require _________ or ____________ substances to function

Answer 24

cofactors
nonprotein

Question 25

Enzymes can be inhibited by ___________ or

Answer 25

competitive
non-competitive inhibitors

Question 26

6 classes of enzymes

Answer 26

Oxidoreductase
Transferase
Hydrolase
Lyase
Isomerase
Ligase