Question 1

Fatty acids are

Accepted Answer

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

Question 2

Which of the following substances is made of lipids?

Accepted Answer

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

Question 3

Organic compounds

Accepted Answer

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

Question 4

Cellulose differs from starch in that

Accepted Answer

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. 
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 5

Which of the following statements regarding nucleotides is false?

Accepted Answer

A) Nucleotides contain lipids. 
B) Nucleotides contain sugar molecules. 
C) Nucleotides can be linked together to form nucleic acids. 
D) Nucleotides contain nitrogenous bases. 
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 6

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

Accepted Answer

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

Question 7

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

Accepted Answer

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

Question 8

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

Accepted Answer

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. 
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 9

The tertiary structure of a polypeptide refers to

Accepted Answer

A) its size. 
B) the presence of pleated sheets. 
C) the amino acids of which it is made. 
D) the overall three-dimensional structure. 
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 10

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?

Accepted Answer

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

Question 11

Which of the following organisms contain the polysaccharide chitin?

Accepted Answer

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

Question 12

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

Accepted Answer

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. 
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 13

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

Accepted Answer

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

Question 14

After reading the paragraph below, answer the questions that follow.
You're the manager of a factory that produces enzyme-washed blue jeans (the enzymes lighten the color of the denim, giving a "faded" appearance). When the most recent batch of fabric came out of the enzyme wash, however, the color wasn't light enough to meet your standards. Your quality control laboratory wants to do some tests to determine why the wash enzymes didn't perform as expected.
-If you could design a modified version of the enzyme to ensure that it would function optimally in the harsh conditions of the washing vat (such as high temperature or high pH), which of the following could you do to achieve this goal?

Accepted Answer

A) Add more amino acids to the end of the protein to make it more hydrophobic. 
B) Change the amino acid sequence slightly to ensure a more stable tertiary structure. 
C) Remove some amino acids from the start of the protein to strengthen its secondary structure. 
D) Change the amino acid sequence drastically to give the enzyme quaternary structure. 
A) Add more amino acids to the end of the protein to make it more hydrophobic. 
B) Change the amino acid sequence slightly to ensure a more stable tertiary structure. 
C) Remove some amino acids from the start of the protein to strengthen its secondary structure. 
D) Change the amino acid sequence drastically to give the enzyme quaternary structure.

Question 15

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?

Accepted Answer

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

Question 16

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

Accepted Answer

A) adding hydrogens, decreasing the number of double bonds in the molecules. 
B) removing water, causing a dehydration synthesis 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. 
A) adding hydrogens, decreasing the number of double bonds in the molecules. 
B) removing water, causing a dehydration synthesis 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 17

Lactose intolerance

Accepted Answer

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. 
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 18

The primary structure of a protein is

Accepted Answer

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. 
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 19

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?

Accepted Answer

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 
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 20

The molecular formula of most monosaccharides represents a multiple of

Accepted Answer

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

Exam 3: The Molecules of Cells

Fatty acids are

Which of the following substances is made of lipids?

Organic compounds

Cellulose differs from starch in that

Which of the following statements regarding nucleotides is false?

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

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

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

The tertiary structure of a polypeptide refers to

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?

Which of the following organisms contain the polysaccharide chitin?

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

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

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?

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

Lactose intolerance

The primary structure of a protein is

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?

The molecular formula of most monosaccharides represents a multiple of

Biology: Exploring Life

The Chemical Basis of Life

A Tour of the Cell

The Working Cell

How Cells Harvest Chemical Energy

Photosynthesis: Using Light to Make Food

The Cellular Basis of Reproduction and Inheritance

Patterns of Inheritance

Molecular Biology of the Gene

How Genes Are Controlled

DNA Technology and Genomics

How Populations Evolve

The Origin of Species

Tracing Evolutionary History

Microbial Life: Prokaryotes and Protists

The Evolution of Plant and Fungal Diversity

The Evolution of Invertebrate Diversity

The Evolution of Vertebrate Diversity

Unifying Concepts of Animal Structure and Function

Nutrition and Digestion

Gas Exchange

Circulation

the Immune System

Control of Body Temperature and Water Balance

Hormones and the Endocrine System

Reproduction and Embryonic Development

Nervous Systems

the Senses

How Animals Move

Plant Structure, Growth, and Reproduction

Plant Nutrition and Transport

Control Systems in Plants

the Biosphere: an Introduction to Earths Diverse Environments

Behavioral Adaptations to the Environment

Population Ecology

Communities and Ecosystems

Conservation Biology

Filters

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