Chemical Basis for Life Questions of the Day

Name______

Period______

Date______

Chemical Basis for Life Questions of the Day

Day 6

1.  Tobin perfomed an experiment in which he mixed varying amounts of enzyme with an excess amount of a certain molecule. He measured the rate of each reaction and recorded his data in the table below.

Enzyme Concentration
(millimoles) / Reaction Rate
(micromoles/minute)
0 / 0
100 / 0.05
200 / 0.10
300 / 0.15
400 / 0.20
500 / 0.25

What can Tobin conclude about the relationship between the enzyme concentration and the reaction rate in the presence of excess molecules?

A. There is a direct relationship; as the enzyme concentration increases, the rate of reaction increases.
B. There is an inverse relationship; as the enzyme concentration increases, the reaction rate decreases.
C. There is no relationship between the enzyme concentration and the reaction rate.
D. The experiment is invalid because it was performed in the presence of excess molecules.

2.  Which of the following enzymes serve as catalysts in metabolism?

I.  Amylase

II.  Lactase

III.  Pepsin

IV.  Polymerase

A.  I, II, and III only

B.  I, II, III, and IV

C.  IV only

D.  I and II only

Name______

Period______

Date______

Chemical Basis for Life Questions of the Day

Day 7

1.  Hydrogen peroxide is a substance that is produced as a by-product of many cell processes. However, hydrogen peroxide is toxic to cells. In fact, if cells are unable to break down hydrogen peroxide, they become poisoned and die.
The chemical reaction for the breakdown of hydrogen peroxide is shown below.

What role does catalase play in this reaction?

A.  Catalase is a reactant that gets used up in the reaction.

3. 

4.  / B.  Catalase is a product that is created during the reaction.

5. 

6.  / C.  Catalase in an enzyme that slows down the reaction.

7. 

8.  / D.  Catalase is an enzyme that speeds up the reaction.

2. An enzyme is a biomolecule that increases the rate of a chemical reaction. An enzyme is a kind of______.

A.  translator
B.  inhibitor
C.  catalyst
D.  Ribosome

Name______

Period______

Date______

Chemical Basis for Life Questions of the Day

Day 8

1. Cellular processes are carried out by many different types of molecules, mostly proteins. The function of each protein molecule depends on its shape which, in turn, is determined by the protein's specific sequence of .

A. triglycerides

B. amino acids

C. monosaccharides

D. nucleotides

2. Organic macromolecules called ______are insoluble in water, are often found in biological membranes and other waterproof coverings, and have the ability to store energy for extended periods of time.

A. carbohydrates

B. lipids

C. nucleic acids

D. proteins

Name______

Period______

Date______

Chemical Basis for Life Questions of the Day

Day 9

1. A water molecule is composed of two hydrogen atoms and one oxygen atom arranged in a bent shape.

Since oxygen is significantly more electronegative than hydrogen, oxygen atoms have a much stronger attraction to shared electrons than does hydrogen. This unequal sharing of electrons and bent shape results in a polar molecule. The oxygen end of the molecule has a slightly negative charge while the hydrogen ends of the molecule have a slightly positive charge.

The composition and polar covalent nature of water allow water molecules to be attracted to and form

A. ionic bonds with free radical ions.

B. hydrogen bonds with other water molecules.

C. covalent bonds with nonpolar molecules.

D. all of these

2. A large carbohydrate molecule is composed of several subunits, such as glucose.

An example of a large carbohydrate molecule is ______.

A. starch

B. glycogen

C. cellulose

D. all of these

Name______

Period______

Date______

Chemical Basis for Life Questions of the Day

Day 10

1. Which of the following are the important, life-sustaining properties of water?

I. cohesive behavior

II. ability to moderate temperature

III. expansion upon freezing

IV. versatility as a solvent

A. I, II, III, and IV

B. I, II, and IV only

C. I and III, and IV only

D. II and III only

2.  Which of the following is true about protein molecules?

A. Protein molecules are made up of strands of DNA joined together by amino acid sequences.

B. The sequence of amino acids that make up a protein molecule do not affect its function.

C. The shape and folded structure of a protein molecule are important in determining its function.

D. Protein molecules have many functions in the body, including the storage of genetic information.