Transcript Biological Chemistry

Chapter 23
Standardized Test Preparation
Preview
• Multiple Choice
• Short Answer
• Extended Response
Chapter 23
Standardized Test Preparation
Multiple Choice
1. Which of the following statements about enzymes is
true?
A. Enzymes can be biological catalysts.
B. Enzymes increase the speed of a chemical
reaction.
C. Enzymes are highly specific.
D. All of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
1. Which of the following statements about enzymes is
true?
A. Enzymes can be biological catalysts.
B. Enzymes increase the speed of a chemical
reaction.
C. Enzymes are highly specific.
D. All of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
2. Which of the following statements about denaturing is
true?
A. Denaturing occurs when a protein unfolds.
B. Denaturing occurs when a carbohydrate is heated.
C. Denaturing does not affect the tertiary structure of
an enzyme.
D. Denaturing increases the rate of a chemical
reaction.
Chapter 23
Standardized Test Preparation
Multiple Choice
2. Which of the following statements about denaturing is
true?
A. Denaturing occurs when a protein unfolds.
B. Denaturing occurs when a carbohydrate is heated.
C. Denaturing does not affect the tertiary structure of
an enzyme.
D. Denaturing increases the rate of a chemical
reaction.
Chapter 23
Standardized Test Preparation
Multiple Choice
3. The process in which molecules in a cell break down
to produce smaller molecules and energy is called
A. glycogenesis.
B. biosynthesis.
C. catabolism.
D. metabolism.
Chapter 23
Standardized Test Preparation
Multiple Choice
3. The process in which molecules in a cell break down
to produce smaller molecules and energy is called
A. glycogenesis.
B. biosynthesis.
C. catabolism.
D. metabolism.
Chapter 23
Standardized Test Preparation
Multiple Choice
4. Which of the following is partially digested by saliva in
the mouth?
A. glucose
B. starch
C. fat
D. protein
Chapter 23
Standardized Test Preparation
Multiple Choice
4. Which of the following is partially digested by saliva in
the mouth?
A. glucose
B. starch
C. fat
D. protein
Chapter 23
Standardized Test Preparation
Multiple Choice
5. In the human body, the storage form of
A. glucose is maltose.
B. triglycerides is protein.
C. carbohydrates is glycogen.
D. nucleic acids is amino acids.
Chapter 23
Standardized Test Preparation
Multiple Choice
5. In the human body, the storage form of
A. glucose is maltose.
B. triglycerides is protein.
C. carbohydrates is glycogen.
D. nucleic acids is amino acids.
Chapter 23
Standardized Test Preparation
Multiple Choice
6. The purpose of insulin is to
A. regulate glucose levels in the body.
B. catalyze the oxidation of fatty acids.
C. stimulate RNA production.
D. initiate DNA replication.
Chapter 23
Standardized Test Preparation
Multiple Choice
6. The purpose of insulin is to
A. regulate glucose levels in the body.
B. catalyze the oxidation of fatty acids.
C. stimulate RNA production.
D. initiate DNA replication.
Chapter 23
Standardized Test Preparation
Multiple Choice
7. Which of the following statements about fats is true?
A. Fats serve as a reserve supply of energy.
B. Fats are stored in the adipose tissue.
C. Fats act as insulators.
D. All of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
7. Which of the following statements about fats is true?
A. Fats serve as a reserve supply of energy.
B. Fats are stored in the adipose tissue.
C. Fats act as insulators.
D. All of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
8. When carbohydrates are unavailable or unable to
provide the energy needs of the body,
A. glucose is converted to glycogen.
B. proteins or fats are used for energy.
C. amino acids form proteins.
D. All of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
8. When carbohydrates are unavailable or unable to
provide the energy needs of the body,
A. glucose is converted to glycogen.
B. proteins or fats are used for energy.
C. amino acids form proteins.
D. All of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
9. Which of the following statements is true?
A. RNA contains the base uracil rather than thymine,
which occurs in DNA.
B. Both RNA and DNA are double-stranded helixes.
C. The ribose sugar unit is in the backbone of DNA.
D. None of the above
Chapter 23
Standardized Test Preparation
Multiple Choice
9. Which of the following statements is true?
A. RNA contains the base uracil rather than thymine,
which occurs in DNA.
B. Both RNA and DNA are double-stranded helixes.
C. The ribose sugar unit is in the backbone of DNA.
D. None of the above
Chapter 23
Standardized Test Preparation
Short Answer
10. Draw a simple dipeptide, and label the functional
groups and peptide linkage.
Chapter 23
Standardized Test Preparation
Short Answer
10. Draw a simple dipeptide, and label the functional
groups and peptide linkage.
Answer: Answers will vary. The —NH2 amino group and a
—COOH carboxylic acid group should be labeled.
Also, the peptide bond should be labeled.
Chapter 23
Standardized Test Preparation
Short Answer
11. Describe the shape of the DNA molecule, and discuss
how the DNA molecule is held in this shape.
Chapter 23
Standardized Test Preparation
Short Answer
11. Describe the shape of the DNA molecule, and discuss
how the DNA molecule is held in this shape.
Answer: DNA is shaped like a twisted ladder. The
double-stranded helix of DNA is held together by
hydrogen bonding between the base pairs.
Chapter 23
Standardized Test Preparation
Extended Response
12. The body has numerous energy reserves. What are
they, and where are they found in the body? Which of
these reserves provides the greatest source of quick
energy?.
Chapter 23
Standardized Test Preparation
Extended Response
12. The body has numerous energy reserves. What are
they, and where are they found in the body? Which of
these reserves provides the greatest source of quick
energy?
Answer: The body stores energy in the form of fat in
adipose tissue, glycogen in the liver, and protein in
muscle and fibrous tissue. The greatest source of
quick energy is the glucose in the blood. Glucose
comes from the stored glycogen in the liver. All types
of proteins (structural, enzymatic, regulator, and
others) can also provide energy to the body.
Chapter 23
Standardized Test Preparation
Extended Response
13. Explain how it is possible to denature a protein
without breaking the polypeptide chain.
Chapter 23
Standardized Test Preparation
Extended Response
13. Explain how it is possible to denature a protein
without breaking the polypeptide chain.
Answer: The properties of a protein relate to the
protein’s secondary, tertiary, and quaternary
structure, which can be changed (denatured)
without affecting the primary structure.