Download 2.2.3 Enzymes Worksheet

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2.2.3 Enzymes Worksheet
Enzymes
Most reactions take place in a number of __________ which need to be _________________________
if the cell is to function properly
______________ are the most important controllers of cellular reactions
Catalysts
_______________ speed up reactions without themselves being involved in the reaction.
______________ are catalysts made of ____________ they speed up a reaction without being used up
themselves in the reaction.
Because enzymes are made in living things they are called ____________________ (or organic
catalysts)
We learned in the section on food that proteins are made when ____________________ join together.
The function of a protein is decided not only by the _______________ of amino acids but also by the
way the protein __________.
Most enzymes are ________________ proteins
How enzymes work
Enzymes are not flat they have a 3D structure
Each enzyme has its own __________________________ that will only “fit” the molecule that the
enzyme is designed to work on.
If the enzyme that breaks down starch into glucose meets a fat molecule it _______________________
and will not be able to work on it.
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Name: _________________________
Enzyme Action
The substance that an enzyme acts on is its __________________
The substance(s) that the enzyme forms is called the ________________
A Catabolic enzyme
Amylase converts ____________ to ______________.
Catabolic as it breaks a __________ molecule into a __________ one.
It is produced by ___________________ in mouth and by the
______________.
An Anabolic Enzyme
______________________________ forms and repairs DNA.
Anabolic as it coverts __________ molecules into more __________ molecules.
Found in almost all living things
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Name: _________________________
Consider This
Amylase is an enzyme found in saliva. It breaks starch molecules into smaller maltose molecules.
What is the substrate?
What is the product?
Will amylase break fats into fatty acids + glycerol?
Why?
Is this an example of a catabolic or an anabolic reaction?
Why?
And This
DNA Polymerase is an enzyme that builds DNA using tiny molecules in our cells.
What is the substrate?
What is the product?
Will amylase build keratin out of peptides?
Why?
Is this an example of a catabolic or an anabolic reaction?
Why?
Enzymes work because they have the correct shape to fit the substrate.
They have a ______________________________________________
shape to fit the substrate.
When enzymes and their substrates meet and come together they form
an _________________________________ complex.
Enzyme Reactions are ___________________.
Like a key can open or close a lock enzymes can ________________________
________________________________.
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Name: _________________________
In the following example the enzyme can break molecule X into Y+Z but it can also combine Y+Z to
form X
Naming Enzymes
Enzymes are named by adding the suffix ______ to the name of their _________________.
Eg.
Enzyme that acts on Amylose (starch) is called ______________.
Enzymes that act on proteins are called __________________.
Inhibitors
Inhibitors attach to enzymes and _______________________________.
When this happens the enzymes are said to be __________________.
Nerve Gases
The nerve gases we hear of terrorists using are often ________________
that attach to enzymes involved in our ___________________________.
Poisoning people the old fashioned way!
______________ denatures an enzyme involved in _____________________.
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Name: _________________________
Beneficial Inhibitors
________________________ affect ______________ in insects causing their death.
__________ can affect ______________ involved in pain causing the pain to stop.
____________________ can affect ______________ in bacteria causing the bacteria to die.
Enzymes at work!
Enzymes work best in certain conditions
Factors that affect enzymes include:
______________
______________
______________ concentration
______________ concentration
We will be examining these in experiments
Temperature
At very low temperatures ice forms, liquids become solids and enzymes can’t work.
As temperature increases molecules start to ___________ and bump into each other
causing the rate of reaction to _______________.
Human enzymes work best at ___________________ (____°C)
Plant Enzymes work best at ____-____ °C
Above certain temperatures enzymes start to lose their __________ the rate of reaction __________.
When the shape is fully lost the enzyme is said to be __________________ this is usually a
___________________ condition.
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Name: _________________________
pH
pH scale goes from 0 -14
0-7 is ___________
7-14 is __________ (or ________________)
Enzymes work over a ________________ pH range
Most enzymes work at pH ____ - ____
Outside this they lose shape and get __________________
The ________________ or best pH is usually pH 7
An Exception!
Is our stomach acid or basic? __________________
Do you think there are enzymes in our stomach? ________________
____________ is an enzyme in the stomach that works best at pH 2!
Immobilised Enzymes
__________________________ is the use of enzyme controlled reactions to produce a product.
Bioprocessing can be used to produce a vast range of products such as ______________, beer,
_____________________, vaccines, methane gas, food flavours, vitamins and perfumes.
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Name: _________________________
Traditionally microorganisms such as _____________ and __________ were used but since
the 1900’s and especially since the 1950’s ______________ are being used.
If enzymes are used freely _________________ in a vessel it can be very wasteful as they are
________ at the end of the process
To prevent this problem enzymes are often _____________________ or fixed.
This means they are ________________ to ______________ or an _________ _______________ and
can be used repeatedly.
How to immobilise enzymes
Physical methods
__________________ where enzymes are physically attached to inactive supports such as glass beads
or ceramics.
_______________________________________________ when enzymes are kept within a membrane.
____________________, sodium alginate is commonly used this allows substrates in and products out.
Chemical Methods
_______________________ enzymes chemically bonded to a support such as glass beads or ceramics.
________________________________. Enzymes are chemically bonded to each other.
Advantages of Immobilised Enzymes
_________________ of enzyme is not affected
Immobilised enzymes can be __________________________ from the product so you can get a pure
sample of product easily.
Immobilised enzymes ______________________ this cuts costs.
Enzymes ________________ become _________________________ when immobilised.
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Name: _________________________
Uses of Immobilised Enzymes
Immobilised glucose isomerase converts ______________ to ______________ which
is used to sweeten drinks.
Penicillin acylase changes the _______________ of penicillin to make more
_________________ that will fight a wider range of bacteria
Lactase converts _____________ to sweeter sugars ______________ and
___________________ which are then used by food manufacturers
Syllabus Can you.......
•
Define the term: enzymes
•
State the nature, folded shape & functions of enzymes.
•
Explain the role of enzymes in plants and animals including role in metabolism
•
Explain the effects of pH & temperature on enzyme activity.
•
State the procedure and advantages of Bio-processing.
•
State the use of Bio-processing.
END
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