Enzymes lesson

Chemical Reactions

& Enzymes

9C Identify and investigate the role of enzymes (Supporting TEKS)

Multiple Choice

What biomolecule do enzymes belong to? 

• Carbohydrate
• Lipid
• Nucleic Acid
• Protein

Multiple Choice

What is the main purpose of enzymes inside of living cells?

• Store Energy for later use by the cell

• Repel water from the cell's surface

• Provide cells with structure and support

• To speed up and direct chemical reactions

Multiple Choice

What is the role of protein in the body?

• Is the main source of energy for the body

• Helps to build and repair body tissue

• Provide warmth and cushioning to the body's organs

• Helps to transport vitamins through the body

• All of the above are roles of protein in the body

Multiple Select

Which elements can be found in proteins?

• C

• H

• N

• P

• O

Multiple Choice

Which is NOT a function of Protiens?

• Chemical reactions of enzymes
• Short term energy
• Immune responce
• cell signaling 

What are some examples or functions of proteins?

Role (Examples){Functions}

●Digestive enzyme (Amylase, lipase, pepsin){Break down nutrients in food into
small pieces that can be readily absorbed}

●Transport (Hemoglobin){Carry substances throughout the body in blood or lymph}

●Structure (Actin, tubulin, keratin){Build different structures, like the cytoskeleton}

●Hormone signaling (Insulin, glucagon){Coordinate the activity of different body systems}

●Defense (Antibodies) {Protect the body from foreign pathogens}

●Contraction (Myosin){Carry out muscle contraction}

●Storage (Legume storage proteins, egg white (albumin)) {Provide food for the
early development of the embryo or the seedling}

Multiple Select

Select all the functions of the proteins

• immune response

• structural support

• hormone signaling

• enzymatic activity

• transport

Match

Match the proteins with their functions

• Amylase

• Hemoglobin

• Insulin

• Collagen

• Antibodies

Breaks down starches

Transports oxygen

Regulates blood sugar

Provides structural support

Fights infections

• Breaks down starches

• Transports oxygen

• Regulates blood sugar

• Provides structural support

• Fights infections

Match

Match the protein to its function

• Albumin

• Myosin

• Lipase

• Glucagon

• Keratin

Food for early development of the embryo

Muscle contraction

Breakdown lipids

Hormone signaling

Structural support

• Food for early development of the embryo

• Muscle contraction

• Breakdown lipids

• Hormone signaling

• Structural support

Chemical Reactions

process that changes one set of chemicals into
another set of chemicals. This involves a change in
chemical bonds.

CO2 + H2O H2CO3

Reactants

Products

what you start with

what you end up with

Multiple Choice

What is underlined in the chemical equation below?

Na + Cl ---> NaCl

• Products

• Reactants

Multiple Choice

In the chemical equation below, the product is....

Na + Cl ---> NaCl

• Na

• NaCL

• Cl

• NaCl

Hotspot

Select all the reactants

Energy

Energy can be released or absorbed whenever
chemical bonds are made or broken.

Many chemical reactions need energy to occur (will
not proceed without a source of energy).

Potential Energy

Multiple Choice

Knowing that energy is stored in the bonds,
which biomolecule holds more energy:

• carbohydrates

• lipids

Activation Energy

energy needed to activate or start a reaction.

Activation Energy

energy needed to activate or start a reaction.

Simply put, to get
this ball to move
down the hill, you
need to put in
some energy first
by pushing it up
(activation energy).

Activation Energy

Enzymes

specialized proteins that act as biological catalyst
(substance that speeds up rate of chemical reaction by lowering activation energy)

Living cells use enzymes to speed up virtually every important chemical reaction that takes place in cells.

These reactions would otherwise be too slow to sustain life.

​

Enzymes
can increase reaction speeds 10¹⁰ times

Enzymes are specific to their substrate. They combine at
the active site to form an enzyme-substrate complex.
The products are the substrate broken apart.

Enzymes

Not used during
reaction.
Enzyme can be
reused for more
reactions.

Name of enzyme derived from reaction it catalyzes
(ends in -ase)

Example: Lactase breaks apart lactose.

Enzymes

Enzymes are specific:
Lactase can only break
down lactose, not
sucrose.

Labelling

Label the image:

Drag labels to their correct position on the image

Active site

Enzyme-substrate complex

Substrate

Products

Enzyme

Labelling

Label the image

Drag labels to their correct position on the image

Enzyme

Products

Enzyme substrate complex

Substrates

Two Models

Lock-and-key: substrate molecules have the right shape to fit an enzyme

Induced Fit: interaction between enzyme and substrate causes the enzyme to change shape to provide a suitable fit.

Some molecules (inhibitors) can interfere with enzyme activity by sitting in the active site or changing the shape of the enzyme.

Inhibitors

decrease enzyme activity

Multiple Choice

Any substance that is acted upon by an enzyme is called a(n)?

• Coenzyme
• Substrate
• Vitamin
• Polypeptide

Multiple Choice

When a molecule can occupy the same active site as the substrate, a situation called __________________ can result

• Competitive lnhibition
• Allosteric Regulation
• Non-Competitive Inhibition
• Feedback Inhibition

Multiple Choice

A receptor site that a molecule can bind to that changes the shape of the active site is called a(n):

• Allosteric Site

• Active Site

• Activation site

• Reactant site

(or cofactors) a substance that works with an enzyme
to change the rate of reaction.

Coenzymes

increase enzyme activity

Multiple Choice

How does a noncompetitive inhibitor decrease reaction rates?

• Binds to the active site

• Binds to the allosteric site

• Increases the free energy

• Increases the substrate concentration

Multiple Choice

Molecules that bind to enzymes and enhance an enzyme's ability are called:

• CoFactors

• Competitive Inhibitors

• Allosteric Inhibitors

Digestive Enzymes and Digestive Enzyme Supplements | Johns Hopkins Medicine

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Match

Match the enzyme with their substrates

• made in the mouth and pancreas; breaks down complex carbohydrates

• produced in the pancreas; helps digest proteins

• secreted by the pancreas; converts fats into fatty acids

• found in the small intestine; breaks down Lactose

• found in the small intestine; breaks down Sucrose

Amylase

Protease

Lipase

Lactase

Sucrase

• Amylase

• Protease

• Lipase

• Lactase

• Sucrase

Open Ended

Brainstorm to explain what
DENATURE
means and how it would affect the enzyme activity

Enzyme activity is affected by pH, temperature, and
concentration of enzyme/substrate

Enzymes can denature(unfold from its 3D structure)
and lose its function under extreme conditions (high
temperature or very acidic/basic pH).

Factors Affecting Enzymes

Enzymes are sensitive
to changes in pH.

-Enzymes found in the
stomach are more
optimal in acidic pH.

-If it is too acidic or too
basic, enzyme will slow
down or denature.

pH

Temperature

Enzymes function optimally
at certain temperatures.

-High temperatures will
inactivate or denature
enzyme

-Warm temperatures
increases speed

-Cold temperatures will
decrease speed.

Multiple Choice

Based on the graph, what is the optimal temperature for this enzyme? 

• 15^oC
• 40^oC
• 30^oC
• 35^oC

When concentration increases, reaction is faster.

When concentration decreases, reaction is slower.

Concentration of
Enzyme/Substrate

Amylase: found in saliva, breaks down carbohydrates

Protease: found in stomach, break down protein

Lipase: found in small intestines, breaks down lipids

Important Enzymes in your Body

Multiple Choice

In the diagram, what is letter A? 

• product
• substrate
• enzyme-substrate complex
• active site

Multiple Choice

Which of the following would NOT denature an enzyme?

• HIGH temperature

• LOW pH

• HIGH pH

• LOW temperature

Multiple Choice

Enzymes are capable of increasing the rate of a chemical reaction within a living cell.  Enzymes accomplish this through which of the following means?

• reducing the number of products   
• reducing the activation energy
• increasing the temperature of the cell
• increasing the concentration of reactants 

Multiple Choice

What happens to the reaction rate if an enzyme is denatured or nonfunctional?

• No change in the reaction rate

• Increase in reaction rate

• Decrease in reaction rate

• Decrease then increase in reaction rate