Question 1

Carbon atoms can form double bonds with other carbon atoms, nitrogen atoms, and oxygen atoms.Double bonds can have important consequences for biological molecules because they are __________ compared to single covalent bonds.

Accepted Answer

A) long 
B) rigid with respect to rotation 
C) weak 
D) unstable

Question 2

Both DNA and RNA are synthesized by covalently linking a nucleoside triphosphate to the previous nucleotide, constantly adding to a growing chain.In the case of DNA, the new strand becomes part of a stable helix.The two strands are complementary in sequence and antiparallel in directionality.What is the principal force that holds these two strands together?

Accepted Answer

A) ionic interactions 
B) hydrogen bonds 
C) covalent bonds 
D) van der Waals interactions

Question 3

A protein chain folds into its stable and unique three-dimensional structure, or conformation, by making many noncovalent bonds between different parts of the chain.Such noncovalent bonds are also critical for interactions with other proteins and cellular molecules.From the list provided, choose the class or classes of amino acids that are most important for the interactions detailed below.
A.forming ionic bonds with negatively charged DNA
B.forming hydrogen bonds to aid solubility in water
C.binding to another water-soluble protein
D.localizing an "integral membrane" protein that spans a lipid bilayer
E.tightly packing the hydrophobic interior core of a globular protein
acidic nonpolar
basic uncharged polar

Accepted Answer

The answer of A protein chain folds into its stable...

Question 4

Table 2-14
-Table 2-14 indicates the number and arrangement of electrons in the first four atomic electron shells for selected elements.On the basis of the information in the chart and what you know about atomic structure, which elements will form ions with a net charge of +2 in solution?

Accepted Answer

A) carbon; sulfur 
B) helium; neon 
C) sodium; potassium 
D) magnesium; calcium

Question 5

Cells require one particular monosaccharide as a starting material to synthesize nucleotide building blocks.Which of the monosaccharides below fills this important role?

Accepted Answer

A) glucose 
B) fructose 
C) ribulose 
D) ribose

Question 6

A.In which scientific unit is the strength of a chemical bond usually expressed? B.If 0.5 kilocalories of energy are required to break 6 × 10²³ bonds of a particular type, what is the strength of this bond?

Accepted Answer

The answer of A.In which scientific unit is the strength...

Question 7

Double covalent bonds are both shorter and stronger than single covalent bonds, but they also limit the geometry of the molecule because they

Accepted Answer

A) create a new arrangement of electron shells. 
B) change the reactivity of the bonded atoms. 
C) limit the rotation of the bonded atoms. 
D) prevent additional bonds from being formed with the bonded atoms.

Question 8

There are 20100 different possible sequence combinations for a protein chain with 100 amino acids.In addition to the amino acid sequence of the protein, what other factors INCREASE the potential for diversity in these macromolecules?

Accepted Answer

A) free rotation around single bonds during synthesis 
B) noncovalent interactions sampled as protein folds 
C) the directionality of amino acids being added 
D) the planar nature of the peptide bond

Question 9

The variety and arrangement of chemical groups on monomer subunits contribute to the conformation, reactivity, and surface of the macromolecule into which they become incorporated.What type of chemical group is circled on the nucleotide shown in Figure 2-41?  Figure 2-41

Accepted Answer

A) pyrophosphate 
B) phosphoryl 
C) carbonyl 
D) carboxyl

Question 10

Match between columns Premises: Any covalently bonded H atom can participate in a hydrogen bond if it comes in close proximity with an oxygen atom that forms part of a water molecule. Protons are constantly moving between water molecules, which means there is an overall equilibrium between hydroxyl ions and hydronium ions in aqueous solutions.
Electrons are always shared equally between covalently bonded atoms.
A strong base is defined as a molecule that can readily remove protons from water.

Accepted Answer

The Answer of True and False is...

Question 11

Match between columns Premises: All proteins and RNAs pass through many unstable conformations as they are folded, finally settling on one single, preferred conformation.
"Nonpolar interactions" is simply another way of saying "van der Waals attractions." Condensation reactions occur in the synthesis of all the macromolecules found in cells.

Accepted Answer

The Answer of False and True is...

Question 12

A covalent bond between two atoms is formed as a result of the

Accepted Answer

A) sharing of electrons. 
B) loss of electrons from both atoms. 
C) loss of a proton from one atom. 
D) transfer of electrons from one atom to the other.

Question 13

The amino acids glutamine and glutamic acid are shown in Figure 2-38.They differ only in the structure of part of their side chains (circled).At pH7, what type of interactions are possible for glutamic acid but not for glutamine?  Figure 2-38

Accepted Answer

A) ionic bonds 
B) hydrogen bonds 
C) van der Waals interactions 
D) covalent bonds

Question 14

Selenium (Se) is an element required in the human body in trace amounts.Selenium is obtained through the diet and levels of selenium found in food depend greatly on the soil where it is grown.Once ingested and absorbed as selenate, it can become incorporated into a small number of polypeptides.These selenoproteins are formed when selenium replaces an element that is found in 2 of the 20 "standard" amino acids.Using your knowledge of atomic structure, the periodic table in Figure 2-7, and the structure of amino acids found in Panel 2-5, deduce which two amino acids may be converted to "seleno" amino acids and used to make selenoproteins.

Accepted Answer

The answer of Selenium (Se) is an element required in...

Question 15

You are trying to make a synthetic copy of a particular protein but accidentally join the amino acids together in exactly the reverse order.One of your classmates says the two proteins must be identical, and bets you $20 that your synthetic protein will have exactly the same biological activity as the original.After having read this chapter, you have no hesitation in staking your $20 that it will not.What particular feature of a polypeptide chain makes you sure your $20 is safe and that the project must be restarted?

Accepted Answer

The answer of You are trying to make a synthetic...

Question 16

Macromolecules in the cell can often interact transiently as a result of noncovalent interactions.These weak interactions also produce stable, highly specific interactions between molecules.Which of the factors below is the most significant in determining whether the interaction will be transient or stable?

Accepted Answer

A) the size of each molecule 
B) the concentration of each molecule 
C) the rate of synthesis 
D) surface complementarity between molecules

Question 17

Carbon 14 is an unstable isotope of carbon that decays very slowly.Compared to the common, stable carbon 12 isotope, carbon 14 has two additional

Accepted Answer

A) electrons. 
B) neutrons. 
C) protons. 
D) ions.

Question 18

Select the answer that BEST completes the following statement: Chemical reactions in living systems occur in an __________ environment, within a narrow range of temperatures.

Accepted Answer

A) optimal 
B) organic 
C) extracellular 
D) aqueous

Question 19

A.Sketch three different ways in which three water molecules could be held together by hydrogen-bonding. B.On a sketch of a single water molecule, indicate the distribution of positive and negative charge (using the symbols δ⁺ and δ⁻). C.How many hydrogen bonds can a hydrogen atom in a water molecule form? How many hydrogen bonds can the oxygen atom in a water molecule form?

Accepted Answer

The answer of A.Sketch three different ways in which three...

Question 20

Figure 2-26
-Larger molecules have hydrogen-bonding networks that contribute to specific, high-affinity binding.Smaller molecules such as urea can also form these networks.How many hydrogen bonds can urea (Figure 2-26) form if dissolved in water?

Accepted Answer

A) 6 
B) 5 
C) 3 
D) 4

Exam 2: Chemical Components of Cells

Carbon atoms can form double bonds with other carbon atoms, nitrogen atoms, and oxygen atoms.Double bonds can have important consequences for biological molecules because they are __________ compared to single covalent bonds.

Table 2-14 -Table 2-14 indicates the number and arrangement of electrons in the first four atomic electron shells for selected elements.On the basis of the information in the chart and what you know about atomic structure, which elements will form ions with a net charge of +2 in solution?

Cells require one particular monosaccharide as a starting material to synthesize nucleotide building blocks.Which of the monosaccharides below fills this important role?

A.In which scientific unit is the strength of a chemical bond usually expressed? B.If 0.5 kilocalories of energy are required to break 6 × 10²³ bonds of a particular type, what is the strength of this bond?

Double covalent bonds are both shorter and stronger than single covalent bonds, but they also limit the geometry of the molecule because they

There are 20¹⁰⁰ different possible sequence combinations for a protein chain with 100 amino acids.In addition to the amino acid sequence of the protein, what other factors INCREASE the potential for diversity in these macromolecules?

The variety and arrangement of chemical groups on monomer subunits contribute to the conformation, reactivity, and surface of the macromolecule into which they become incorporated.What type of chemical group is circled on the nucleotide shown in Figure 2-41? Figure 2-41

Indicate whether the statements below are TRUE or FALSE.If a statement is false, explain why it is false.

Indicate whether the statements below are TRUE or FALSE.If a statement is false, explain why it is false.

A covalent bond between two atoms is formed as a result of the

The amino acids glutamine and glutamic acid are shown in Figure 2-38.They differ only in the structure of part of their side chains (circled) .At pH₇, what type of interactions are possible for glutamic acid but not for glutamine? Figure 2-38

Carbon 14 is an unstable isotope of carbon that decays very slowly.Compared to the common, stable carbon 12 isotope, carbon 14 has two additional

Select the answer that BEST completes the following statement: Chemical reactions in living systems occur in an __________ environment, within a narrow range of temperatures.

Figure 2-26 -Larger molecules have hydrogen-bonding networks that contribute to specific, high-affinity binding.Smaller molecules such as urea can also form these networks.How many hydrogen bonds can urea (Figure 2-26) form if dissolved in water?

Exam 2: Chemical Components of Cells

Carbon atoms can form double bonds with other carbon atoms, nitrogen atoms, and oxygen atoms.Double bonds can have important consequences for biological molecules because they are __________ compared to single covalent bonds.

Table 2-14 -Table 2-14 indicates the number and arrangement of electrons in the first four atomic electron shells for selected elements.On the basis of the information in the chart and what you know about atomic structure, which elements will form ions with a net charge of +2 in solution?

Cells require one particular monosaccharide as a starting material to synthesize nucleotide building blocks.Which of the monosaccharides below fills this important role?

A.In which scientific unit is the strength of a chemical bond usually expressed? B.If 0.5 kilocalories of energy are required to break 6 × 1023 bonds of a particular type, what is the strength of this bond?

Double covalent bonds are both shorter and stronger than single covalent bonds, but they also limit the geometry of the molecule because they

There are 20100 different possible sequence combinations for a protein chain with 100 amino acids.In addition to the amino acid sequence of the protein, what other factors INCREASE the potential for diversity in these macromolecules?

The variety and arrangement of chemical groups on monomer subunits contribute to the conformation, reactivity, and surface of the macromolecule into which they become incorporated.What type of chemical group is circled on the nucleotide shown in Figure 2-41? Figure 2-41

Indicate whether the statements below are TRUE or FALSE.If a statement is false, explain why it is false.

Indicate whether the statements below are TRUE or FALSE.If a statement is false, explain why it is false.

A covalent bond between two atoms is formed as a result of the

The amino acids glutamine and glutamic acid are shown in Figure 2-38.They differ only in the structure of part of their side chains (circled) .At pH7, what type of interactions are possible for glutamic acid but not for glutamine? Figure 2-38

Carbon 14 is an unstable isotope of carbon that decays very slowly.Compared to the common, stable carbon 12 isotope, carbon 14 has two additional

Select the answer that BEST completes the following statement: Chemical reactions in living systems occur in an __________ environment, within a narrow range of temperatures.

Figure 2-26 -Larger molecules have hydrogen-bonding networks that contribute to specific, high-affinity binding.Smaller molecules such as urea can also form these networks.How many hydrogen bonds can urea (Figure 2-26) form if dissolved in water?

A.In which scientific unit is the strength of a chemical bond usually expressed? B.If 0.5 kilocalories of energy are required to break 6 × 10²³ bonds of a particular type, what is the strength of this bond?

There are 20¹⁰⁰ different possible sequence combinations for a protein chain with 100 amino acids.In addition to the amino acid sequence of the protein, what other factors INCREASE the potential for diversity in these macromolecules?

The amino acids glutamine and glutamic acid are shown in Figure 2-38.They differ only in the structure of part of their side chains (circled) .At pH₇, what type of interactions are possible for glutamic acid but not for glutamine? Figure 2-38