CH. 2

Question 1

The polymerization of different types of macromolecules is similar in many respects. Which of the following principles below is least likely to be common to all methods of polymerization of macromolecules?

Answer 1

polymerization is passive, requiring little ATP

Question 2

An enzyme synthesized in the lab is found to have little activity when compared to the enzyme extracted from cell culture. Both enzymes were examined and have identical amino acid composition. What is the best explanation for the lack of activity of the synthesized enzyme?

Answer 2

the synthesized enzyme was not folded correctly because molecular chaperones were not present

Question 3

the nucleotide triphosphate molecules in DNA are linked in the 5’?3’ by a(n) ______ bridge

Answer 3

phosphodiester

Question 4

Carbon can form the _______ covalent bond.

Answer 4

single, double, triple

Question 5

While synthesizing a new blue pigment, a chemist notices that the new compound congregates between an aqueous (water) environment and a hydrophobic environment. When added to a mixture of oil and water, the pigment creates a blue ring around the droplets of oil. Which of the following statements best describes this new pigment? The pigment is

Answer 5

is amphipathic, having polar and nonpolar regions

Question 6

The term amphipathic refers to those molecules that are

Answer 6

charged at one end and nonpolar at the other

Question 7

polymers are synthesized by condensation reactions and broken down into their constituent monomers by hydrolysis reactions

Answer 7

true

Question 8

why do polar substances such as NaCl dissolve so readily in water?

Answer 8

• spheres of hydrogen from between the water and the ions

- the charged ends of the water molecules are able to surround the oppositely charged salt ions

Question 9

Which of the following statements about the polymerization of macromolecules is false?

Answer 9

water is added to join the monomers of the macromolecules

Question 10

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. This phenomenon can be explained by the exclusion of hydrophobic groups from the aqueous surface, called the hydrophobic effect.

Answer 10

True

Question 11

the amino acid referred to as “helix breaker” (because it lacks the hydrogen atom needed for hydrogen bonding) is

Answer 11

proline

Question 12

which of the following is not a characteristic of DNA?

Answer 12

has ribose

Question 13

in the lab , you choose to design a simple experiment to distinguish between hydrophilic and hydrophobic substances. You start by adding equal amounts of vinegar and oil to a container. After shaking , the vinegar and oil levels separate, based upon polarity and density. To this you add glucose and sodium citrate and shake again. Where do you expect to find the glucose and sodium citrate in greatest quantities?

Answer 13

both will concentrate in the vinegar layer

Question 14

macromolecules are synthesized by a series of steps. Monomers are systematically added to the growing polymer. Therefore people who are trying to lose weight are asked to drink plenty of water since water is released in the synthesis of polymers like fats (condensation reaction), water will be needed for the breakdown of fat molecules (hydrolysis)

Answer 14

true

Question 15

the chemical nature of each amino acid is determined by which of the following groups?

Answer 15

R

Question 16

Hydrogen bonding is most important in stabilizing the _____ structure of many proteins

Answer 16

secondary

Question 17

Based on the following amino acid sequence, which region(s) in/are hydrophobic? 1[K-K-N-Q]-2[A-G-G-V]-3[Y-C-S-R]-4[H-E-C-Y]

Answer 17

region 2

Question 18

A phosphate group, a sugar (ribose or deoxyribose), and a base are the major parts of a nucleotide, whereas a sugar and a base are the major parts of a nucleoside

Answer 18

true

Question 19

detergents are best able to dissolve oil from fabric or dishes during washing because

Answer 19

charged end is associated with a sphere of hydrogen, while non polar end interacts with oil droplets

Question 20

disulfide bonds are often found to stabilize which of the following levels of protein structure?

Answer 20

tertiary

Question 21

the term amphipathic describes the characteristic of some molecules that have ____

Answer 21

both a polar and non polar region

Question 22

which one of the following biological polymer is mismatched with its monomer?

Answer 22

cellulose- amino acid

Question 23

monomers are removed from polymers by ____ reactions

Answer 23

hydrolysis

Question 24

the primary structure of a protein

Answer 24

• is important for determining the secondary and tertiary structure of a protein
• is simply the order of amino acids from one end of the protein to another
• is important both genetically and structurally
• is the linear sequence of amino acids that are linked by peptide bonds

Question 25

Fibrous proteins have an extensive _______ Structure allowing them to be highly ordered and repetitive

Answer 25

secondary

Question 26

which of the following is notA possible non-covalent Interaction?

Answer 26

Polar covalent bonding

Question 27

The hierarchical Nature of a cellular structure is accurately illustrated in which of the following list of substances (from smallest to largest)?

Answer 27

Nucleotides, DNA, chromosomes, nucleus, cell