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