Deck 3: The Molecules of Cells

Question 1

Which of the following statements regarding carbon is false?

A) Carbon has a tendency to form covalent bonds.
B) Carbon has the ability to bond with up to six other atoms.
C) Carbon has the capacity to form single and double bonds.
D) Carbon has the ability to bond together to form extensive branched or unbranched "carbon skeletons."

Answer 1

B

Question 2

A molecule with the formula C55H110O55 is probably a(n)

A) oil.
B) steroid.
C) protein.
D) polysaccharide.

Answer 2

D

Question 3

Which of the following statements about the monomers and polymers found in living organisms is false?

A) Cells typically make all of their macromolecules from a set of 40-50 common monomers and a few other ingredients that are rare.
B) The monomers used to make polymers are essentially universal.
C) Monomers serve as building blocks for polymers.
D) Monomers are joined together by the process of hydrolysis.

Answer 3

D

Question 4

Which of the following is a carboxyl group?

A) -C-O
B) -OH
C) -NH2
D) -COOH

Question 5

Which of the following statements about the functional groups of organic compounds is false?

A) Functional groups may help make organic compounds hydrophilic.
B) Many biological molecules have two or more functional groups.
C) Functional groups participate in chemical reactions.
D) All functional groups include a carbon atom.

Question 6

Sucrose is formed

A) from two glucose molecules.
B) from two monosaccharides through dehydration reactions.
C) when ionic bonds link two monosaccharides.
D) when glucose and lactose are combined.

Question 7

What is the general function of enzymes within a cell?

A) to promote the synthesis of monomers
B) to induce chemical reactions
C) to stop chemical reactions
D) to speed up chemical reactions

Question 8

Which of the following statements about dehydration reactions is false?

A) One monomer loses a hydrogen atom, and the other loses a hydroxyl group.
B) H2O is formed as the monomers are joined.
C) Covalent bonds are formed between the monomers.
D) Animal digestive systems utilize this process to break down food.

Question 9

Which of the following statements about hydrocarbons is false?

A) Hydrocarbons are inorganic compounds.
B) Hydrocarbons contain only carbon and hydrogen atoms.
C) Hydrocarbons consist of atoms linked by single or double bonds.
D) Hydrocarbons can form straight, branched, or ringed structures.

Question 10

Propanol and isopropanol are isomers. This means that they have

A) the same molecular formula but different chemical properties.
B) different molecular formulas but the same chemical properties.
C) the same molecular formula and the same chemical properties.
D) the same molecular formula but represent different states of the compound.

Question 11

The molecular formula of most monosaccharides represents a multiple of

A) CH3O.
B) CH2O.
C) CHO.
D) CHO2.

Question 12

Which of the following is an amino group?

A) -OH
B) -NH2
C) -COOH
D) -CO

Question 13

Many names for sugars end in the suffix

A) -acid.
B) -ose.
C) -hyde.
D) -ase.

Question 14

A hydroxyl group is

A) also called a carbonyl group.
B) characteristic of proteins.
C) characteristic of alcohols.
D) composed of two oxygen atoms.

Question 15

Which of the following functional groups is capable of regulating gene expression?

A) -OH
B) -COOH
C) -CO
D) -CH3

Question 16

Which of the following contains a carboxyl and an amino group?

A) amino acid
B) fat
C) sugar
D) glucose

Question 17

The results of dehydration reactions can be reversed by

A) condensation reactions.
B) hydrolysis reactions.
C) polymerization reactions.
D) the addition of an amino group.

Question 18

Lactose intolerance is the inability to

A) produce milk proteins.
B) produce lactose.
C) digest cellulose.
D) digest lactose.

Question 19

Lactose intolerance

A) is common in people of all ages, from infancy to adulthood.
B) is most common in people of European descent.
C) can currently be treated by gene therapy to treat the underlying cause.
D) does not affect the consumption of beverages made from soy or rice.

Question 20

Organic compounds

A) always contain nitrogen.
B) are synthesized only by animal cells.
C) always contain carbon.
D) always contain oxygen.

Question 21

Which of the following substances is made of lipids?

A) DNA
B) cellulose
C) steroids
D) enzymes

Question 22

Fatty acids are

A) composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio.
B) composed of carbon, hydrogen, glycerol, and a phosphate group.
C) composed of hydrocarbon chains and a carboxyl group.
D) composed of four linked rings.

Question 23

Cellulose differs from starch in that

A) starch is formed by plants and cellulose by animals.
B) most animals cannot break down cellulose, whereas starch is easily digested.
C) starch is made of glucose monomers, whereas cellulose is made of fructose monomers.
D) cellulose is highly branched, whereas starch is unbranched.

Question 24

The storage form of carbohydrates is ________ in animals and ________ in plants.

A) starch; glycogen
B) glycogen; starch
C) cellulose; glycogen
D) glycogen; cellulose

Question 25

The development of heart disease can result from a diet high in

A) fiber.
B) protein.
C) saturated fats.
D) sugars.

Question 26

If you were to add olive oil to your food as part of a diet to lower your risk of heart disease, you would use olive oil that

A) is liquid at room temperature.
B) is hydrogenated.
C) is modified to be solid at room temperature.
D) has lard added to it.

Question 27

A major type of lipid found in cell membranes is

A) saturated fats.
B) phospholipids.
C) glycerol.
D) unsaturated fats.

Question 28

Fatty acids with double bonds between some of their carbons are said to be

A) unsaturated.
B) saturated.
C) completely hydrogenated.
D) monoglycerides.

Question 29

Cows can derive nutrients from cellulose because

A) they produce the enzymes that break down cellulose.
B) they chew their food so thoroughly that cellulose fibers are broken down.
C) their intestinal tract contains cellulose-hydrolyzing microorganisms.
D) they convert cellulose into starch, which is easily broken down in the intestinal tract.

Question 30

Which of the following lists contains only polysaccharides?

A) sucrose, starch, and cellulose
B) starch, amino acids, and glycogen
C) cellulose, starch, and glycogen
D) fructose, cellulose, and glucose

Question 31

A disaccharide forms when

A) two monosaccharides join by dehydration reactions.
B) two starches join by dehydration reactions.
C) two monosaccharides join by hydrolysis.
D) two starches join by hydrolysis.

Question 32

A diet high in animal products and hydrogenated vegetable margarine may increase the risk for heart disease. This is because

A) most animal fats are unsaturated and most hydrogenated vegetable margarines contain high levels of steroids.
B) most hydrogenated vegetable margarines are hydrogenated oils and most animal products contain high levels of phospholipids.
C) most animal fats are used for energy storage and most hydrogenated vegetable margarines contain high levels of unsaturated fats.
D) most animal fats are saturated and many hydrogenated vegetable margarines contain high levels of trans fats.

Question 33

An oil may be converted into a substance that is solid at room temperature by

A) adding hydrogens, decreasing the number of double bonds in the molecules.
B) removing water, causing a dehydration reaction to occur.
C) removing hydrogens, increasing the number of double bonds in the molecules.
D) cooling it, so that double bonds form and the fats solidify.

Question 34

What feature of fats makes them hydrophobic?

A) Fats have carboxyl groups.
B) Fats include one glycerol molecule.
C) Fats have polar fatty acids.
D) Fats have nonpolar hydrocarbon chains.

Question 35

Foods that are high in fiber are most likely derived from

A) plants.
B) dairy products.
C) red meats.
D) fish.

Question 36

Which of the following organisms contain the polysaccharide chitin?

A) animals and plants
B) plants and bacteria
C) fungi and insects
D) insects and plants

Question 37

Which of the following statements about anabolic steroids is false?

A) They cause a general buildup of muscle mass.
B) They often cause the body to reduce its normal output of sex hormones.
C) They promote bone growth.
D) They can stimulate mood swings and violent behavior.

Question 38

Which of the following statements about animal cell lipids is false?

A) Fats are a form of lipid that function to store energy.
B) Phospholipids are important components of cell membranes.
C) Many lipids function as enzymes.
D) Cholesterol is a type of lipid that is a component of cell membranes and steroid hormones.

Question 39

Which of the following statements regarding triglyceride molecules is false?

A) Triglycerides consist of three fatty acids attached to a glycerol molecule.
B) Triglycerides play a role in energy storage.
C) Triglycerides are a type of fat.
D) Triglycerides are hydrophilic.

Question 40

A phospholipid is composed of

A) one fatty acid molecule linked to three glycerol molecules.
B) one glycerol molecule linked to three phosphate groups.
C) one fatty acid molecule linked to one glycerol molecule and two phosphate groups.
D) one glycerol molecule linked to one phosphate group and two fatty acids.

Question 41

Glucose molecules are to starch as ________ are to proteins.

A) oils
B) amino acids
C) fatty acids
D) monosaccharides

Question 42

Which of the following would be correctly classified as a protein?

A) cholesterol
B) starch
C) an enzyme
D) cellulose

Question 43

Which of the following statements regarding nucleotides is false?

A) Nucleotides contain lipids.
B) Nucleotides contain sugar molecules.
C) Nucleotides can be linked together to form nucleic acids.
D) Nucleotides contain nitrogenous bases.

Question 44

A protein containing more than one polypeptide chain exhibits the ________ level of protein structure.

A) primary
B) secondary
C) tertiary
D) quaternary

Question 45

A scientist suspects that the food in an ecosystem may have been contaminated with radioactive nitrogen over a period of months. Which of the following substances could be examined for radioactivity to test the hypothesis?

A) the cell walls of plants growing in the ecosystem
B) the hair produced by humans living in the ecosystem
C) the sugars produced during photosynthesis by plants growing in the ecosystem
D) the cholesterol in the cell membranes of organisms living in the ecosystem

Question 46

Proteins differ from one another because

A) the peptide bonds linking amino acids differ from protein to protein.
B) the sequence of amino acids in the polypeptide chain differs from protein to protein.
C) each protein contains its own unique sequence of sugar molecules.
D) the number of nucleotides found in each protein varies from molecule to molecule.

Question 47

How are genes used by cells to build proteins?

A) The genes in DNA direct the synthesis of an RNA molecule, which is used to build a protein.
B) The genes in RNA direct the synthesis of a DNA molecule, which is used to build a protein.
C) DNA is transcribed into an amino acid sequence.
D) The genes in RNA direct the synthesis of proteins directly.

Question 48

Peptide bonds

A) are used to form amino acids.
B) form between fatty acids.
C) are formed by a hydrolysis reaction.
D) link amino acids.

Question 49

The primary structure of a protein is

A) an alpha helix or a pleated sheet.
B) the amino acid sequence of the polypeptide chain.
C) composed of two or more polypeptide chains.
D) maintained by hydrogen bonds.

Question 50

Mad cow disease serves as an example of how interdependent ________ and ________ are to protein.

A) solubility; texture
B) form; construction
C) structure; function
D) adaptability; development

Question 51

Amino acids can be distinguished from one another by

A) the number of R groups found on the amino acid molecules.
B) the chemical properties of their R groups.
C) the type of bond between the R group and the rest of the amino acid molecule.
D) the chemical properties of their amino and carboxyl groups.

Question 52

The tertiary structure of a polypeptide refers to

A) its size.
B) the presence of pleated sheets.
C) the amino acids of which it is made.
D) the overall three-dimensional structure.

Question 53

Structural proteins

A) include receptor molecules.
B) include hemoglobin.
C) are found in hair and tendons.
D) include ovalbumin, a protein found in egg white.

Question 54

Which of the following characteristics of a protein will remain intact if the protein is denatured?

A) the shape of the protein
B) the function of the protein
C) the number of amino acids in the protein
D) the binding properties of the protein

Question 55

Which of the following is an example of secondary structure in a protein?

A) a particular amino acid sequence
B) an alpha helix
C) a globular shape
D) the joining of two polypeptide chains

Question 56

Which of the following options correctly pairs a polymer and its monomer?

A) cellulose, amino acids
B) DNA, nucleotides
C) collagen, nucleic acids
D) RNA, ribose

Question 57

You work for a company that manufactures food products. A new "wonder food" is being distributed by a rival company. The researchers in your company determine that the "wonder food" contains only carbon, oxygen, and hydrogen. At this point, your researchers can say with certainty that the food

A) includes proteins.
B) could only be made of triglycerides.
C) could only be made of carbohydrates.
D) does not include proteins or nucleic acids.

Question 58

DNA differs from RNA because DNA

A) contains thymine in place of uracil.
B) consists of a single rather than a double polynucleotide strand.
C) contains the sugar ribose rather than the sugar deoxyribose.
D) contains phosphate groups not found in RNA.

Question 59

In what part of the world is the mutation for lactose tolerance most concentrated?

A) East Asia
B) South America
C) northern Europe
D) North America

Question 60

Which of the following statements about enzymes is false?

A) They increase the rate of chemical reactions.
B) They function as chemical catalysts.
C) They regulate virtually all chemical reactions in a cell.
D) They are monomers used to build proteins.

Question 61

When microbes are in the dark, they do not produce molecules called carotenoids because the PR proteins are bound to DNA. In the light, however, carotenoids are produced because the PR proteins unbind the DNA. Which of the following graphs best summarizes these statements about carotenoid production in microbes?

A)

B)

C)

D)

Question 62

Which of the following foods would be least likely to contribute to the development of heart disease?

A) margarine
B) butter
C) bacon
D) fish oil

Question 63

What is the complementary sequence to the DNA strand TCGATGG?

A) TCGATGG
B) GGTAGCT
C) AGCUACC
D) AGCTACC

Question 64

Lysozyme is an enzyme that breaks down bacterial cell walls and is found in your tears, mucus, and saliva. A mutation occurs in the gene for lysozyme that results in a lysine (a positively charged amino acid) being substituted for an arginine (also a positively charged amino acid). Do you think that the mutant lysozyme will function similarly to the normal lysozyme?

A) no, because all changes in protein primary sequence result in functional differences
B) no, because changing lysine to arginine will cause the protein to denature
C) yes, because both lysine and arginine are positively charged so the tertiary structure and therefore function should be similar
D) yes, because protein function stays the same no matter what mutations occur

Question 65

Which meal is high in fiber, low in saturated fats, and high in unsaturated fats?

A) beef, potatoes, and carrots
B) eggs and bacon
C) black beans, cheese, lettuce, and sour cream
D) spaghetti noodles with olive oil and broccoli

Question 66

The recent National Health and Nutrition Examination Survey found a 275% greater risk of what disease for individuals who consumed more than 25% of their daily calories from added sugars?

A) diabetes
B) cardiovascular disease
C) stomach cancer
D) hypertension

Question 67

You have a cup of vegetable oil and a vial full of normal phospholipids. What would you predict would happen if you dropped the phospholipids into the cup of vegetable oil?

A) The phospholipids would form a sphere with the heads on the inside.
B) The phospholipids would form a sphere with the tails on the inside.
C) The phospholipids would float on the surface of the oil with the tails in the air.
D) The phospholipids would float on the surface of the oil with the heads in the air.

Question 68

Following are the structures of three fatty acids: palmitic acid, stearic acid, and oleic acid. What combination of these fatty acids could you use to make a fat that is liquid at room temperature?

A) one palmitic acid, one stearic acid, and one oleic acid
B) three palmitic acids
C) two palmitic acids and one stearic acid
D) one stearic acid, one oleic acid, and one phosphate group

Question 69

How are these two amino acids attached?

A) amino group to amino group
B) amino group to carboxyl group
C) carboxylic acid group to carboxyl group
D) through a hydrolysis reaction

Question 70

These two molecules are structural isomers. What is the difference between them?

A) the number of carbon atoms
B) the number of hydrogen atoms
C) the location of a double-bonded oxygen atom
D) Only one of them has a double bond between carbon atoms.

Question 71

You identify a molecule in a pizza that is a polymer; has oxygen, hydrogen, and sulfur atoms; and is hydrophilic. What kind of molecule is it?

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

Question 72

Why did the lactose tolerance mutation in the East African herders spread so rapidly within the population?

A) Milk provided calcium for strong bones.
B) It was a selective advantage for survival during droughts and cold winters.
C) Lactose was a better source of energy than glucose.
D) Milk was a good source of protein during the summer harvests.

Question 73

What components make up a nucleotide?

A) a sugar and a phosphate group only
B) a nitrogenous base and a phosphate group only
C) a nitrogenous base and a sugar only
D) a sugar, a nitrogenous base, and a phosphate group

Question 74

Myosin is a contractile protein found in muscles that is composed of three pairs of subunits, two heavy chains, and two pairs of two different types of light chains, for a total of six subunits. Myosin contains what level(s) of protein structure?

A) primary only
B) primary and secondary only
C) primary, secondary, and tertiary only
D) primary, secondary, tertiary, and quaternary

Question 75

Which type of fat was found to contribute the most relative risk of developing heart disease?

A) saturated fat
B) monounsaturated fat
C) polyunsaturated fat
D) trans fat

Question 76

What is the correct flow of information in gene expression?

A) DNA→RNA→protein
B) RNA→DNA→protein
C) Protein→RNA→DNA
D) DNA→protein→RNA

Question 77

Shown here is a nutrition facts label for 1 cup of whole cow's milk. Which of the following is most abundant by weight in 1 cup of whole milk? (1,000 mg = 1 g)

A) the total amount of lipids
B) polysaccharides
C) monosaccharides
D) protein

Question 78

If you ate a 100% plant-based (vegan) diet, what molecule would you never eat?

A) starch
B) cellulose
C) cholesterol
D) phospholipids

Question 79

Below is a molecule of caffeine. Which of the following features are not present in a molecule of caffeine?

A) a carbonyl group
B) a carboxyl group
C) a methyl group
D) a double bond

Question 80

Suppose that an adult black bear adds 50 pounds of fat in order to survive while hibernating through the winter. Approximately how much glycogen would a bear have to add to achieve a similar feat?

A) 25 pounds
B) 50 pounds
C) 75 pounds
D) 100 pounds