Question 1

Which of the following contributes to the stability of the DNA double helix?

Accepted Answer

A) hydrophobic interactions between aromatic bases at the center of the double helix 
B) hydrogen bonding between the phosphate and sugar groups in the backbone of the double helix 
C) covalent bonding between complementary purine and pyrimidine bases. 
D) ionic bonds between the negatively charged phosphate groups and the positively charged pyrimidine bases. 
E) hydrophobic interactions between aromatic bases at the center of the double helix and ionic bonds between the negatively charged phosphate groups and the positively charged pyrimidine bases 
A) hydrophobic interactions between aromatic bases at the center of the double helix 
B) hydrogen bonding between the phosphate and sugar groups in the backbone of the double helix 
C) covalent bonding between complementary purine and pyrimidine bases. 
D) ionic bonds between the negatively charged phosphate groups and the positively charged pyrimidine bases. 
E) hydrophobic interactions between aromatic bases at the center of the double helix and ionic bonds between the negatively charged phosphate groups and the positively charged pyrimidine bases

Question 2

Lipid rafts are

Accepted Answer

A) regions of the membrane that are high in sphingolipids,which facilitate communication with the external environment of the cell. 
B) important regions of membrane structure comprised of phospholipids. 
C) regions not typically associated with signal transduction. 
D) regions where greater concentrations of sphingolipids are on the inner side of the membrane. 
E) rafts of lipids inside of the cell that serve to store energy. 
A) regions of the membrane that are high in sphingolipids,which facilitate communication with the external environment of the cell. 
B) important regions of membrane structure comprised of phospholipids. 
C) regions not typically associated with signal transduction. 
D) regions where greater concentrations of sphingolipids are on the inner side of the membrane. 
E) rafts of lipids inside of the cell that serve to store energy.

Question 3

Because of their structure,trans fats resemble ________ fatty acids in shape and are produced artificially during the manufacture of shortening and margarine.

Accepted Answer

The answer of Because of their structure,trans fats resemble ________...

Question 4

A peptide bond

Accepted Answer

A) is a covalent bond between the carboxyl carbon of one amino acid and the amino nitrogen of a second amino acid. 
B) is a covalent bond between the functional R groups of adjacent amino acids. 
C) is a covalent bond between the NH group of one polypeptide and the CO group of an adjacent polypeptide that holds together multimeric proteins. 
D) is a noncovalent bond that dictates the tertiary structure of a protein. 
E) is a covalent bond between adjacent glucose molecules in a peptide. 
A) is a covalent bond between the carboxyl carbon of one amino acid and the amino nitrogen of a second amino acid. 
B) is a covalent bond between the functional R groups of adjacent amino acids. 
C) is a covalent bond between the NH group of one polypeptide and the CO group of an adjacent polypeptide that holds together multimeric proteins. 
D) is a noncovalent bond that dictates the tertiary structure of a protein. 
E) is a covalent bond between adjacent glucose molecules in a peptide.

Question 5

The function of triglycerides is

Accepted Answer

A) to store energy. 
B) to form semipermeable membranes. 
C) to transport substances in and out of cells. 
D) store information. 
E) Both B and C are correct. 
A) to store energy. 
B) to form semipermeable membranes. 
C) to transport substances in and out of cells. 
D) store information. 
E) Both B and C are correct.

Question 6

As a protein is being synthesized,the correct folding of the protein is aided by the movement of nonpolar amino acids toward the inner areas of the protein.How can this phenomenon be explained? How will this influence other levels of protein structure?

Accepted Answer

The exclusion of hydrophobic g

Question 7

The term amphipathic describes the characteristic of some molecules that have

Accepted Answer

A) two polar regions. 
B) only a single polar region. 
C) both a polar and a nonpolar region. 
D) no polar regions. 
E) two nonpolar regions. 
A) two polar regions. 
B) only a single polar region. 
C) both a polar and a nonpolar region. 
D) no polar regions. 
E) two nonpolar regions.

Question 8

Which of the following is false?

Accepted Answer

A) Phospholipids are important in membrane structure. 
B) Serine is a molecule that may be part of a phosphoglyceride. 
C) Phosphatidic acid contains two fatty acids and a phosphate group. 
D) Sphingolipids are the predominant phospholipid in membranes. 
E) Phospholipids are amphipathic. 
A) Phospholipids are important in membrane structure. 
B) Serine is a molecule that may be part of a phosphoglyceride. 
C) Phosphatidic acid contains two fatty acids and a phosphate group. 
D) Sphingolipids are the predominant phospholipid in membranes. 
E) Phospholipids are amphipathic.

Question 9

Structurally,starch exists as both unbranched polysaccharide chains called ________ and branched polysaccharide chains called ________.

Accepted Answer

amylose; a

Question 10

Fatty acids are ________; they function in the cell as ________.

Accepted Answer

A) short chains of double-bonded carbon molecules; storage lipids 
B) short chains of double-bonded carbon molecules; vitamins and cofactors 
C) four-ringed hydrocarbon molecules; key components of membranes 
D) long,unbranched hydrocarbon chains with a carboxyl group at one end; building blocks for other lipids 
E) short chains of double-bonded carbon molecules; vitamins,cofactors,and storage lipids 
A) short chains of double-bonded carbon molecules; storage lipids 
B) short chains of double-bonded carbon molecules; vitamins and cofactors 
C) four-ringed hydrocarbon molecules; key components of membranes 
D) long,unbranched hydrocarbon chains with a carboxyl group at one end; building blocks for other lipids 
E) short chains of double-bonded carbon molecules; vitamins,cofactors,and storage lipids

Question 11

In 1953 the structure of DNA was determined to be a ________.

Accepted Answer

The answer of In 1953 the structure of DNA was...

Question 12

Triglycerides are composed of three fatty acids attached to a molecule of ________.

Accepted Answer

The answer of Triglycerides are composed of three fatty acids...

Question 13

RNA and DNA differ

Accepted Answer

A) in that RNA contains ribose and DNA contains deoxyribose. 
B) in that RNA contains nucleosides and DNA contains nucleotides. 
C) in that RNA contains uracil and DNA contains thymine. 
D) both A and C. 
E) All of these are correct. 
A) in that RNA contains ribose and DNA contains deoxyribose. 
B) in that RNA contains nucleosides and DNA contains nucleotides. 
C) in that RNA contains uracil and DNA contains thymine. 
D) both A and C. 
E) All of these are correct.

Question 14

Which of the following pairs correctly matches the monomer with its polymer?

Accepted Answer

A) peptides; proteins 
B) amino acids; polysaccharides 
C) glucose; proteins 
D) terpenes; nucleic acids 
E) nucleotides; nucleic acids 
A) peptides; proteins 
B) amino acids; polysaccharides 
C) glucose; proteins 
D) terpenes; nucleic acids 
E) nucleotides; nucleic acids

Question 15

5'-ATAGGGCTT-3' is a short sequence of a strand of DNA.What will be the complementary sequence of the other strand? What will be the complementary mRNA sequence derived from the second strand of DNA? Be sure to indicate the 5' or 3' ends of each sequence.

Accepted Answer

Complementary DNA: 3

Question 16

A general trend in the structure of many biomolecules is

Accepted Answer

A) that the order and bonding of monomers form the basis for the secondary and tertiary structure of the polymer. 
B) that they are all soluble in water independent of the size of the polymer. 
C) that each class of biomolecule forms one type of secondary structure independent of the order of the monomers in the polymer. 
D) that each class of biomolecule can form either fibrous or globular conformations depending on the chemical conditions inside the cell. 
E) that four different monomers form the basis for the functional and structural properties of each polymer. 
A) that the order and bonding of monomers form the basis for the secondary and tertiary structure of the polymer. 
B) that they are all soluble in water independent of the size of the polymer. 
C) that each class of biomolecule forms one type of secondary structure independent of the order of the monomers in the polymer. 
D) that each class of biomolecule can form either fibrous or globular conformations depending on the chemical conditions inside the cell. 
E) that four different monomers form the basis for the functional and structural properties of each polymer.

Question 17

Cholesterol is a ________,which ________.

Accepted Answer

A) terpene; is the basis for many animal and plant vitamins 
B) fatty acid; functions in energy storage 
C) steroid; is a component of eukaryotic membranes 
D) steroid; is the basis for many animal and plant hormones 
E) steroid; is a component of eukaryotic membranes and is the basis for many animal and plant hormones 
A) terpene; is the basis for many animal and plant vitamins 
B) fatty acid; functions in energy storage 
C) steroid; is a component of eukaryotic membranes 
D) steroid; is the basis for many animal and plant hormones 
E) steroid; is a component of eukaryotic membranes and is the basis for many animal and plant hormones

Question 18

Complementary relationships between purines and pyrimidines

Accepted Answer

A) allow adenine to form two hydrogen bonds with thymine (or uracil)and guanine to form three hydrogen bonds with cytosine to form double-stranded nucleic acids. 
B) allow the interaction of the oppositely charged amino acids to form the tertiary structure of proteins. 
C) allow adjacent bases in a nucleotide chain to stack tightly,stabilizing the DNA double helix. 
D) provide highly ordered,repetitive bonding to form α helices and β sheets within proteins. 
E) Both A and C are correct. 
A) allow adenine to form two hydrogen bonds with thymine (or uracil)and guanine to form three hydrogen bonds with cytosine to form double-stranded nucleic acids. 
B) allow the interaction of the oppositely charged amino acids to form the tertiary structure of proteins. 
C) allow adjacent bases in a nucleotide chain to stack tightly,stabilizing the DNA double helix. 
D) provide highly ordered,repetitive bonding to form α helices and β sheets within proteins. 
E) Both A and C are correct.

Question 19

You are investigating the structure of the seeds of a newly discovered tropical plant.There is storage material inside the seed.You treat the seed with peptidase (an enzyme that breaks peptide bonds),glycoside hydrolases (an enzyme that breaks β glycosidic bonds),and amylase (an enzyme that breaks α glycosidic bonds).Only the amylase appears to dissolve the storage material in the seed.What does this tell you about the identity of the storage material?

Accepted Answer

A) The seed contains fibrous proteins to store carbon and energy. 
B) The seed contains lipids to store carbon and energy. 
C) The seed contains starch to store carbon and energy. 
D) The seed contains cellulose to store carbon and energy. 
E) The seed contains globular proteins to store carbon and energy. 
A) The seed contains fibrous proteins to store carbon and energy. 
B) The seed contains lipids to store carbon and energy. 
C) The seed contains starch to store carbon and energy. 
D) The seed contains cellulose to store carbon and energy. 
E) The seed contains globular proteins to store carbon and energy.

Question 20

Which of the following is a possible function of a terpene?

Accepted Answer

A) cell surface receptor 
B) vitamin 
C) enzyme 
D) motility 
E) structure 
A) cell surface receptor 
B) vitamin 
C) enzyme 
D) motility 
E) structure

Exam 3: The Macromolecules of the Cell

Which of the following contributes to the stability of the DNA double helix?

Lipid rafts are

Because of their structure,trans fats resemble ________ fatty acids in shape and are produced artificially during the manufacture of shortening and margarine.

A peptide bond

The function of triglycerides is

As a protein is being synthesized,the correct folding of the protein is aided by the movement of nonpolar amino acids toward the inner areas of the protein.How can this phenomenon be explained? How will this influence other levels of protein structure?

The term amphipathic describes the characteristic of some molecules that have

Which of the following is false?

Structurally,starch exists as both unbranched polysaccharide chains called ________ and branched polysaccharide chains called ________.

Fatty acids are ________; they function in the cell as ________.

In 1953 the structure of DNA was determined to be a ________.

Triglycerides are composed of three fatty acids attached to a molecule of ________.

RNA and DNA differ

Which of the following pairs correctly matches the monomer with its polymer?

5'-ATAGGGCTT-3' is a short sequence of a strand of DNA.What will be the complementary sequence of the other strand? What will be the complementary mRNA sequence derived from the second strand of DNA? Be sure to indicate the 5' or 3' ends of each sequence.

A general trend in the structure of many biomolecules is

Cholesterol is a ________,which ________.

Complementary relationships between purines and pyrimidines

Which of the following is a possible function of a terpene?

A Preview of Cell Biology

The Chemistry of the Cell

Cells and Organelles

Bioenergetics: the Flow of Energy in the Cell

Enzymes: the Catalysts of Life

Membranes: Their Structure,function,and Chemistry

Transport Across Membranes: Overcoming the Permeability Barrier

Chemotrophic Energy Metabolism: Glycolysis and Fermentation

Chemotrophic Energy Metabolism: Aerobic Respiration

Phototrophic Energy Metabolism: Photosynthesis

The Endomembrane System

Cytoskeletal Systems

Cellular Movement: Motility and Contractility

Beyond the Cell: Cell Adhesions, cell Junctions, and Extracellular Structures

The Structural Basis of Cellular Information: Dna, chromosomes, and the Nucleus

DNA Replication, repair, and Recombination

Gene Expression: Ithe Genetic Code and Transcription

Gene Expression: Iiprotein Synthesis and Sorting

The Regulation of Gene Expression

Molecular Biology Techniques for Cell Biology

Signal Transduction Mechanisms: Ielectrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Iimessengers and Receptors

The Cell Cycle and Mitosis

Sexual Reproduction,meiosis,and Genetic Recombination

Filters

Structurally,starch exists as both unbranched polysaccharide chains called and branched polysaccharide chains called .

Fatty acids are ; they function in the cell as .

Cholesterol is a ,which .