Question 1

Triglycerides are a poor source of stored energy.

Accepted Answer

Triglycerides are actually a great source of stored energy. When broken down, each gram of triglyceride can provide the body with 9 calories of energy, which is more than double the 4 calories provided by a gram of carbohydrate or protein.

Question 2

Hydrogen bonds are too weak to bind atoms together to form molecules, but they do hold different parts of a single large molecule in a specific three-dimensional shape.

Accepted Answer

Hydrogen bonds are relatively weak compared to chemical bonds between atoms, but they can hold different parts of a large molecule (such as a protein or DNA) in specific shapes through interactions between hydrogen atoms and other atoms like oxygen or nitrogen.

Question 3

The fact that no chemical bonding occurs between the components of a mixture is the chief difference between mixtures and compounds.

Accepted Answer

Chemical bonding occurs between the components of compounds, whereas in mixtures, different substances are simply mixed together without forming new chemical bonds.

Question 4

Mixtures are combinations of elements or compounds that are physically blended together but are not bound by chemical bonds.

Accepted Answer

Mixtures are composed of two or more substances that are physically mixed but not chemically combined, meaning they can be separated through physical means.

Question 5

The lower the pH, the higher the hydrogen ion concentration.

Accepted Answer

This statement is true. pH is a measure of the acidity or basicity of a solution, with lower pH values indicating higher acidity. Acidity is caused by the concentration of hydrogen ions (H+), so as pH decreases, the concentration of H+ increases.

Question 6

A dipeptide can be broken into two amino acids by dehydration synthesis.

Accepted Answer

A dipeptide is broken into two amino acids by hydrolysis, not dehydration synthesis. Dehydration synthesis is the process that joins amino acids together to form peptides, releasing water as a byproduct.

Question 7

Covalent bonds are generally less stable than ionic bonds.

Accepted Answer

Covalent bonds involve sharing of electrons between atoms, resulting in stable molecules. Ionic bonds involve transfer of electrons, resulting in ions held together by electrostatic attraction which is generally stronger than covalent bonds. Therefore, ionic bonds are generally less stable than covalent bonds.

Question 8

O mega-3 fatty acids appear to decrease the risk of heart disease.

Accepted Answer

Omega-3 fatty acids have been shown to have a protective effect against heart disease by reducing inflammation, lowering triglyceride levels, and improving overall heart health.

Question 9

Chemical properties are determined primarily by neutrons.

Accepted Answer

Chemical properties are determined primarily by electrons, not neutrons. Neutrons play a role in determining the physical properties of an element, such as its atomic mass and stability.

Question 10

All organic compounds contain carbon.

Accepted Answer

This statement is true. All organic compounds contain carbon.

Question 11

Glycogen, the storage form of glucose, is primarily stored in skeletal muscle and liver cells.

Accepted Answer

Glycogen is primarily stored in skeletal muscle and liver cells for quick energy access.

Question 12

-Phosphate.

Accepted Answer

The answer of 
-Phosphate....

Question 13

The acidity of a solution reflects the concentration of free hydrogen ions in the solution.

Accepted Answer

The concentration of free hydrogen ions in a solution determines the pH, which is a measure of acidity.

Question 14

Isotopes differ from each other only in the number of electrons the atom contains.

Accepted Answer

Isotopes differ from each other in the number of neutrons they contain, which affects their atomic mass. The number of electrons in an atom is determined by the number of protons, which remains the same for all isotopes of a particular element.

Question 15

A charged particle is generally called an ion or electrolyte.

Accepted Answer

A charged particle can either be an ion (an atom or molecule with an unequal number of protons and electrons) or an electrolyte (a substance that dissociates into ions in solution and conducts electricity).

Question 16

A chemical bond is an energy relationship between outer electrons and neighboring atoms.

Accepted Answer

A chemical bond is indeed an energy relationship between outer electrons and neighboring atoms. This energy relationship results in the formation of a stable molecule or compound.

Question 17

The pH of body fluids must remain fairly constant for the body to maintain homeostasis.

Accepted Answer

Yes, this is true. Maintaining a stable pH is important for proper cellular function and enzyme activity in the body, and any significant changes in pH can be harmful. The body has mechanisms in place to regulate pH, such as the use of buffers and the kidneys' role in excreting excess acids or bases.

Question 18

About 60% to 80% of the volume of most living cells consists of organic compounds.

Accepted Answer

About 60% to 80% of the volume of most living cells consists of water, not organic compounds. Organic compounds make up a significant portion of a cell's mass, but water is the most abundant molecule in cells.

Question 19

Glucose is an example of a monosaccharide.

Accepted Answer

Glucose is a simple sugar and a monosaccharide.

Question 20

It is the difference in the R group that makes each amino acid chemically unique.

Accepted Answer

The R group (also called side chain) is the variable component of an amino acid and different R groups give each amino acid its distinct chemical properties.

Quiz 2: Chemistry Comes Alive