Deck 2: Chemical Principles

Question 1

Identify the following reaction: NH₄OH "NH₃ + H₂O

A) dehydration synthesis reaction
B) exchange reaction
C) reversible reaction
D) hydrolysis reaction
E) ionic reaction

Answer 1

C

Question 2

What do genes consist of?

A) nucleic acids
B) proteins
C) carbohydrates
D) lipids

Answer 2

A

Question 3

Figure 2.3

What kind of bond is at the arrow in Figure 2.3?

A) double covalent bond
B) hydrogen bond
C) peptide bond
D) disulfide bridge
E) ionic bond

Answer 3

C

Question 4

Structurally, ATP is most like which type of molecule?

A) carbohydrate
B) lipid
C) nucleic acid
D) protein

Question 5

What is the type of bond between ions in salt?

A) covalent bond
B) hydrogen bond
C) ionic bond

Question 6

An E. coli culture that has been growing at 37°C is moved to 25°C. Which of the following changes must be made in its plasma membrane?

A) The number of saturated chains must increase.
B) The number of phosphate groups must increase.
C) The viscosity must increase.
D) The number of unsaturated chains must increase.
E) No changes are necessary.

Question 7

Table 2.1
Using the information in Table 2.1, calculate the number of moles in 92 grams of ethanol, C₂H₅OH.

A) 1
B) 2
C) 3
D) 4
E) The answer cannot be determined.

Question 8

Two antiparallel strands of DNA combine to form a double helix. The specific interactions that permit this phenomenon occur by way of bonds between .

A) ionic; deoxyriboses
B) hydrogen; deoxyriboses
C) ionic; phosphate groups
D) hydrogen; nitrogenous bases
E) ionic; nitrogenous bases

Question 9

Identify the following reaction: HCl + NaHCO₃ -NaCl + H₂CO₃

A) dehydration synthesis reaction
B) hydrolysis reaction
C) reversible reaction
D) ionic reaction
E) exchange reaction

Question 10

Which of the following is a base?

A) C₂H₅OCOOH -H⁺ + C₂H₅OCOO^-
B) NaOH -Na⁺ + OH^-
C) C₂H₅OH
D) H₂O -H⁺ + OH^-
E) H₂CO

Question 11

A scientist wants to perform a test that will indicate whether a nucleic acid sample is composed of RNA or DNA. Testing for the presence of which of the following is most appropriate in this situation?

A) uracil
B) nitrogen
C) thymine
D) guanine
E) phosphate

Question 12

Figure 2.1

Which compound in Figure 2.1 is an ester?

A) a
B) b
C) c
D) d
E) e

Question 13

Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope ³⁵S. After a 48- hour incubation, the ³⁵S would most likely be found in the S. cerevisiae's

A) water.
B) nucleic acids.
C) proteins.
D) carbohydrates.
E) lipids.

Question 14

What is the type of bond holding hydrogen and oxygen atoms in the H₂O molecule?

A) ionic bond
B) hydrogen bond
C) covalent bond

Question 15

Table 2.1
Using the information in Table 2.1, calculate the molecular weight of ethanol, C₂H₅OH.

A) 33
B) 34
C) 96
D) 46
E) The answer cannot be determined.

Question 16

The antimicrobial drug imidazole inhibits sterol synthesis. This would most likely interfere with

A) prokaryotic plasma membranes.
B) eukaryotic plasma membranes.
C) bacterial cell walls.
D) genes.
E) fungal cell walls.

Question 17

Table 2.2
Which of the following statements about the reactions in Table 2.2 is FALSE?

A) They are dissociation reactions.
B) They are exchange reactions.
C) They are reversible reactions.
D) They are ionization reactions.
E) They occur when the reactants are dissolved in water.

Question 18

Identify the following reaction: Glucose + Fructose -Sucrose + Water

A) hydrolysis reaction
B) reversible reaction
C) ionic reaction
D) dehydration synthesis reaction
E) exchange reaction

Question 19

Antacids neutralize acid by the following reaction. Identify the salt in the following equation: Mg(OH)₂ + 2HCl -MgCl₂ + H₂O

A) HCl
B) H₂O
C) MgCl₂
D) Mg(OH)₂
E) None of the answers is correct.

Question 20

Most amino acids found in cells demonstrate what type of chirality?

A) D- isomers
B) A- isomers
C) L- iosmers
D) B- isomers
E) C- isomers

Question 21

Which of the following is the type of bond between molecules of water in a beaker of water?

A) covalent bond
B) hydrogen bond
C) ionic bond

Question 22

Which molecule is composed of a chain of amino acids?

A) nucleic acid
B) lipid
C) protein
D) carbohydrate

Question 23

What is the type of bond between carbon, hydrogen, and oxygen atoms in organic molecules?

A) ionic bond
B) hydrogen bond
C) covalent bond

Question 24

What is the type of bond between the hydrogen of one molecule and the nitrogen of another molecule?

A) ionic bond
B) hydrophobic bond
C) hydrogen bond
D) disulfide bond
E) covalent bond

Question 25

Two glucose molecules are combined to make a maltose molecule. What is the chemical formula for maltose?

A) C₁₂H₂₂O₁₁
B)C₁₂H₂₄SO₁₂
C)C₁₂H₂₃O₁₀
D) C₆H₁₂O₆
E) C₃H₆O₃

Question 26

Which of the following statements regarding protein structure is FALSE?

A) Secondary structures are formed only from hydrogen bonds.
B) Tertiary structures are formed only from covalent bonds.
C) Quaternary structures involved multiple polypeptides.
D) The primary structure is formed by covalent bonding between amino acid subunits.

Question 27

Which of the following statements is FALSE?

A) Water molecules are formed by hydrolysis.
B) Salts readily dissolve in water.
C) Water freezes from the top down.
D) Water is a polar molecule.
E) Water is a part of a dehydration synthesis reaction.

Question 28

Starch, dextran, glycogen, and cellulose are polymers of

A) amino acids.
B) fatty acids.
C) glucose.
D) acids.
E) nucleic acids.

Question 29

Desulfovibrio bacteria can perform the following reaction: S^6- -S^2- . These bacteria are

A) hydrolyzing sulfur.
B) oxidizing sulfur.
C) synthesizing sulfur.
D) reducing sulfur.

Question 30

Which type of molecule contains - NH₂ groups?

A) nucleic acid
B) protein
C) triglycerides
D) carbohydrate

Question 31

If you viewed one single protein using a microscope, you would observe multiple structures.

A) secondary
B) tertiary
C) primary
D) primary and secondary
E) secondary and tertiary

Question 32

In Figure 2.1, which is an alcohol?

A) a
B) b
C) c
D) d
E) e

Question 33

Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope ³²P. After a 48- hour incubation, the majority of the ³²P would be found in the S. cerevisiae's

A) water.
B) carbohydrates.
C) cell wall.
D) proteins.
E) plasma membrane.

Question 34

Figure 2.1

Which compound in Figure 2.1 is an organic acid?

A) a
B) b
C) c
D) d
E) e

Question 35

Which type of molecule is composed of (CH₂O) units?

A) lipid
B) protein
C) carbohydrate
D) nucleic acid

Question 36

If an amino acid contained a hydrocarbon as its side group, in which of the following categories could it be appropriately designated?

A) polar
B) basic
C) hydrophilic
D) acidic
E) nonpolar

Question 37

Which type of molecule NEVER contains a phosphate group?

A) nucleic acid
B) triglycerides
C) lipid
D) ATP

Question 38

Which of the following pairs is mismatched?

A) H₂SO₄ "2H⁺ + SO₄^2- - acid
B) MgSO₄ "Mg²⁺ + SO₄^2- - salt
C) KH₂PO₄ "K⁺ + H₂PO₄^- - acid
D) NaOH "Na⁺ + OH^- - base
E) HF "H⁺ + F^- - acid

Question 39

Which type of molecule contains the alcohol glycerol?

A) carbohydrate
B) protein
C) phospholipids
D) DNA

Question 40

Figure 2.2

Archaea differ from bacteria in the composition of the cell membrane lipids. Archaea have
Ether- bonded lipids, shown in part _ of Figure 2.2, and bacteria have ester- bonded lipids, shown in part of Figure 2.2.

A) b;
C B) d; c
C) a; d
D) b; a
E) c; d

Question 41

All chemical reactions are, in theory, reversible.

Question 42

Individual covalent bonds are stronger than individual ionic bonds.

Question 43

Which of the following is the type of bond holding K⁺and I^-ions in KI?

A) covalent bond
B) ionic bond
C) hydrogen bond

Question 44

Figure 2.5

Use Figure 2.5 to answer the following. Starch, cellulose, dextran, and glycogen are polysaccharides. How are they similar? To what are their different properties due? Why can't an enzyme that hydrolyzes starch degrade cellulose?

Question 45

Which of the following statements about the atom ¹² C is FALSE? 6

A) Its atomic weight is 12.
B) Its atomic number is 6.
C) It has 12 neutrons in its nucleus.
D) It has 6 protons in its nucleus.
E) It has 6 electrons orbiting the nucleus.

Question 46

Compare a molecule of a nucleotide to ATP. Could a cell simply insert ATP into DNA without altering it? Explain.

Question 47

Which are the primary molecules making up plasma membranes in cells?

A) nucleic acids
B) carbohydrates
C) lipids
D) proteins

Question 48

Covalent bonds are always shared equally.

Question 49

Based upon the valence numbers of the elements magnesium (2) and hydrogen (1), predict how many covalent bonds would form between these atoms to achieve the full complement of electrons in their outermost energy shells.

A) one
B) two
C) three
D) four

Question 50

Any compound that contains carbon is only considered to be organic.

Question 51

A basic solution is expected to contain more hydrogen ions than hydroxyl ions.

Question 52

Identify the following reaction: Lactose + H₂O -Glucose + Galactose

A) exchange reaction
B) dehydration synthesis reaction
C) reversible reaction
D) ionic reaction
E) hydrolysis reaction

Question 53

The formation of ADP from ATP can be defined as a hydrolytic reaction.

Question 54

There are some forms of life on Earth that can survive without water.

Question 55

All forms of life function optimally at a pH of 7.

Question 56

The density of liquid water is greater than the density of ice.

Question 57

A scientist claims that when a protein is denatured, it can be expected that its secondary structure will more likely be retained when compared to all other levels of protein structure structures. Do you agree? Explain.

Question 58

Elements only achieve the full complement of electrons in outermost energy cells by donating or sharing electrons.