Chapter 3 Test

A major type of lipid found in cell membranes is

phospholipids

If you want to promote the development of atherosclerotic disease, you would eat a diet high in

saturated fats

Genetic information is encoded in the

sequence of nucleotides in DNA

Propanol and isopropanol are isomers. This means that they have

the same molecular formula but different chemical properties

Proteins differ from one another because

the sequence of amino acids in the polypeptide chain differs from protein to protein

Cows can derive nutrients from cellulose because

their intestinal tract contains cellulose-hydrolyzing microorganisms

A disaccharide forms when

2 monosaccharides join by dehydration synthesis

A phospholipid is composed of

1 glycerol molecule linked to 1 phosphate group and 2 fatty acid molecules

The glucose produced by a plant is used to make the carbohydrates, proteins, fats, and nucleic acids of the plant. Which statement is true about the process of converting sugars into other molecules?

Glucose contains all of the elements needed to produce the carbohydrates and fats, but other elements must come from the soil if the plant is to produce proteins and nucleic acids

Which one of the following is an amino group?

NH2

Suppose you wanted to make margarine using a plant oil. How would you alter the oil molecules to make the oil solid at room temperature?

add hydrogen to change the double bonds in the fatty acids to single bonds

One way to convert an oil into a substance that is solid at room temperature is to

add hydrogens, decreasing the number of double bonds in the molecules

Which one of the following statements about the functional groups of organic compounds is not true?

all functional groups include a carbon atom of the organic compound's skeleton

A triglyceride

all of the choices are correct

Characteristics of carbon that contribute to its ability to form an immense diversity of organic molecules include its

all of the choices are correct

Monosaccharides can be joined together by a process called dehydration synthesis. Which of the following statements is/are true of this process?

all of the choices are correct

Nucleotides

all of the choices are correct

Which of the following factors can result in the denaturation of a protein?

all of the choices can result in the denaturation of a protein

Organic compounds

always contain carbon and are synthesized by cells

Glucose molecules are to starch as ____ are to proteins

amino acids

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

an alpha helix

Which one of the following statements is not true? Enzymes

are typically consumed by the reactions they promote

Which one of the following statements about spider silk is not true?

by weight, spider silk is greater in strength to steel

Which one of the following substances is not a lipid?

cellulose

Which one of the following lists contains only polysaccharides?

cellulose, starch, and glycogen

A hydroxyl group is

characteristic of alcohols

Hydrocarbons

contain only carbon and hydrogen atoms

DNA differs from RNA because DNA

contains thymine in place of uracil

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

does not include proteins or nucleic acids

Which one of the following statements about Linus Pauling is not true? Linus Pauling

first described the double-helix shape of DNA

Sucrose is formed

from 2 monosaccharides by dehydration synthesis

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

glycogen.....starch

Molecules that taste sweet

have a shape that binds tightly to sweet taste receptors

Peptide bonds

link amino acids

Which one of the following is not true about animal cell lipids?

many lipids function as enzymes

Which one of the following statements about the monomers and polymers found in living organisms is not true?

monomers are joined together by the process of hydrolysis

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

most animal fats are saturated and most animal products contain high levels of triglycerides

Cellulose differs from starch in that

most animals cannot break down cellulose, whereas starch is easily digested

In salad dressings, oil quickly separates from vinegar because oils are

nonpolar

Foods that are high in fiber are most likely derived from

plants

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

polysaccharide

The ____ structure of a protein consists of a chain of amino acids assembled in a specific order

primary

Which one of the following statements about anabolic steroids is not true? Anabolic steroids

promote bone growth

Spider silk is made of

proteins

Which list below consists of only polymers?

proteins, lipids, nucleic acids, polysaccharides

A protein containing more than 1 polypeptide chain exhibits the ____ level of protein structure

quaternary

Which one of the following statements about androstenedione is not true?

studies show that taking androstenedione greatly increases the production of male sex hormones

Amino acids can be distinguished from one another by

the chemical properties of their R groups

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

the hair produced by humans living in the ecosystem

Which one of the following will not be affected by the denaturation of a protein?

the number of amino acids in the protein

The tertiary structure of a polypeptide refers to

the overall three-dimensional structure

Which one of the following is not the proper pairing of a polymer and its monomer?

triglyceride and steroid

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

unsaturated

Which one of the following statements is not true about waxes? Waxes are

used as a starting material for making steroids

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

was liquid at room temperature

You now know that the old "oil and water don't mix" is true. Why?

water exhibits polarity and oil does not

The molecular formula of most monosaccharides represents a multiple of

CH2O

Because water and oil don't mix, water is not very effective at washing away oily dirt. The ability of soap to mix with both water and oily dirt allows dirt to be washed away. Which statement provides the most logical chemical explanation for this phenomenon?

Soap molecules have charged regions and neutral regions; the charged regions are attracted to water molecules; the neutral regions are attracted to oils

The results of dehydration synthesis can be reversed by

a hydrolysis reaction and digestion