Question

question 15 (4 points)
(01.01 mc)
which of the following best describes what happens to an enzyme after it catalyzes a chemical reaction?
o a its mass decreases since part of the molecule is used up
o b it is unchanged and can be used again for the same chemical reaction
o c it becomes chemically bonded to the products of the reaction
o d its shape changes, giving it different chemical and physical properties

question 16 (4 points)
(01.02 mc)
which of the following best describes the relationship between the shape of enzymes and the reactions they catalyze?
o a the shape of an enzyme depends on the reaction that it needs to catalyze
o b enzymes with more active sites can catalyze several reactions at once
o c the shape of an enzyme determines which reaction it can catalyze
o d enzymes change shape after they catalyze a reaction and become waste products

question 17 (4 points)
(01.02 mc)
an enzyme inhibitor works with the enzyme in a chemical reaction. which statement best describes how an enzyme inhibitor and an enzyme work in a catalyzed reaction?
o a the enzyme inhibitor catalyzes the reverse reaction, which counteracts the work of the enzyme
o b the enzyme inhibitor attacks and destroys the enzyme, which prevents the enzyme from helping in the reaction
o c the enzyme inhibitor binds to the products of the reaction, which makes the work of the enzyme unproductive
o d the enzyme inhibitor fits into the enzymes active site, which prevents the enzyme from catalyzing the reaction

question 18 (4 points)
(01.02 mc)
why is the sequence of nucleotides important to the properties of a nucleic acid?
o a it stores energy
o b it retains and transmits important biological information
o c it stores energy and provides covering to avoid water loss
o d it stores energy and provides structural support for cells

question 19 (4 points)
(01.02 lc)
fats and steroids are examples of which macromolecule?
o a carbohydrates
o b lipids
o c proteins
o d nucleic acids

Explanation:

• Question 15: Enzymes are catalysts that remain unchanged after a reaction and can be reused. They do not get used up or chemically - bond to products.
• Question 16: The shape of an enzyme's active site is specific and determines which reaction it can catalyze.
• Question 17: Enzyme inhibitors work by binding to the enzyme's active site, preventing the substrate from binding and thus inhibiting the reaction.
• Question 18: The sequence of nucleotides in a nucleic acid is crucial for retaining and transmitting biological information like genetic code.
• Question 19: Fats and steroids are examples of lipids, which are a class of macromolecules.

Answer:

• Question 15: b. It is unchanged and can be used again for the same chemical reaction.
• Question 16: c. The shape of an enzyme determines which reaction it can catalyze.
• Question 17: d. The enzyme inhibitor fits into the enzyme's active site, which prevents the enzyme from catalyzing the reaction.
• Question 18: b. It retains and transmits important biological information.
• Question 19: b. Lipids