Biochemistry Notes

Multiple Choice

Enzymes are

• Lipids

• Proteins

• Carbohydrates

• Nucleic Acids

Multiple Choice

What 3 letters do enzymes typically end in?

• -ose

• -ase

• -ese

• -tic

Multiple Choice

Which of these is most likely an enzyme?  

• Sucrose

• Galactose

• Fructose

• Amylase

Enzyme Specificity - The shape of the enzyme (structure) fits it's substrate (function)

Multiple Choice

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

• Coenzyme

• Substrate

• Vitamin

• Polypeptide

Multiple Choice

Each enzyme only has 1 substrate that will fit its active site.  What is this called?

• reusablility

• denaturation

• specificity

• fragility

Multiple Choice

Letter D...

• active site

• enzyme

• substrate

• products

Multiple Choice

Letter B...

• active site

• enzyme

• substrate

• products

Multiple Choice

Letter c...

• active site

• enzyme

• substrate

• products

Multiple Choice

Enzymes are important for...

• Digestion

• Fighting germs

• Building other proteins

• All of the above and more!

Enzymes speed up chemical reactions (Catalysts)

• Activation energy is the energy needed to start a chemical reaction.

• The less activation energy needed (smaller hill to climb) the faster the reaction will happen

• Enzymes speed up reactions by lowering the activation energy

Multiple Choice

What is the purpose of an enzyme?

• give permission for the reaction

• raise activation energy

• speed up reactions

• control how many reactions occur

Multiple Choice

What is a substance called if it speeds up a chemical reaction?

• reusable

• catalyst

• specific

• fragile

Multiple Choice

Which of the following best explains why enzymes are necessary for many cellular reactions?

• Enzymes supply the oxygen necessary for the reactions

•  Enzymes change reactants from solid to liquids during the reactions.

• The reactions take up too much space in the cell if the enzymes are missing.

• The reactions are too slow to meet the needs of the cell if enzymes are missing. 

Multiple Choice

The graph shows how enzymes affect reactions in cells. Which statement best summarizes the information shown in the graph?

• Enzymes increase the energy of the reactants.

• Enzymes decrease the energy level of the products.

• Enzyme decrease the activation energy of the reaction.

• Enzymes reverse the direction of the reaction.

Multiple Choice

An enzyme speeds up a chemical reaction in the cell but can only be used once.  True or False? 

• true

• false

Multiple Choice

After the enzyme and substrate bind together and perform the reaction, what does the substrate become?

• a substrate

• an enzyme

• a product

• an active site

Multiple Select

Which two factors can affect enzyme activity?

• Light intensity

• pH

• Moisture

• Temperature

Multiple Choice

What happens when enzymes are heated to a high temperature?

• The enzymes die.

• The shapes of the enzyme are altered (denatured)

• The enzymes' amino acid sequence changes.

• The enzymes remain the same

Multiple Choice

If an enzyme is denatured, what happens to the shape of the active site?

• It becomes deformed and does not match the substrate

• It becomes expanded and can fit more of the substrate

• It becomes smaller and the substrate also shrinks

• It becomes reversed and the reaction will go backwards

Multiple Choice

Which of the following conclusions can be drawn from this graph?

• The optimum pH of the enzyme is 6.6.

• The optimum pH of the enzyme is 5.8

• The enzyme’s activity increases as pH increases 5.0 to 9.0

• The enzyme’s activity is greater around pH of 8.0 .

Multiple Choice

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

• 15^oC

• 40^oC

• 30^oC

• 35^oC

Multiple Choice

Which enzyme has an optimum temperature of 40 degrees Celsius?

• Enzyme X

• Enzyme Y