anatomy test 2
What happens to an enzyme that is subjected to extremely high temperatures?
It becomes denatured.
Why does the hemoglobin molecule qualify as a quaternary protein structure?
It has four interacting globular subunits.
Why is water particularly effective as a solvent?
Its polarity creates positive and negative regions that interact with many types of molecules.
Why are lipid deposits important as energy reserves?
Lipids provide twice as much energy as carbohydrates provide.
Which of the following are characteristics of electrolytes?
They are soluble in water, able to conduct electrical currents, and inorganic.
A solute that removes hydrogen ions from a solution is ________.
a base
The unequal sharing of electrons in a molecule of water is an example of ________.
a polar covalent bond
The small molecules that form chains to build proteins are called ________.
amino acids
A solute that dissociates to release hydrogen ions and causes a decrease in pH is ________.
an acid
A salt may best be described as ________.
an inorganic molecule consisting of a cation and an anion
What are the smallest stable chemical units of matter?
atoms
What are isotopes of an element?
atoms whose nuclei contain different numbers of neutrons
The ability of water to maintain a relatively constant temperature and then prevent rapid changes in body temperature is due to its ________.
capacity to absorb and distribute heat
What are the four major classes of organic compounds?
carbohydrates, lipids, proteins, and nucleic acids
A carbohydrate molecule is made up of ________.
carbon, hydrogen, and oxygen
A molecule that is hydrophobic ________.
could be a fat or an oil
An enzyme can catalyze a reaction by ________.
decreasing the activation energy
Organic catalysts made by a living cell to promote a specific reaction are called ________.
enzymes
Special proteins that are involved in metabolic regulation are called ________.
enzymes
Which type of bond has the most important effects on the properties of water and the shapes of complex molecules?
hydrogen bond
The protons in an atom are found only ________.
in the nucleus
The attraction between cations and anions is important in ________.
ionic bonds
The major difference between inorganic and organic compounds is that inorganic compounds are usually ________.
not structurally made from carbon and hydrogen
What are the three subatomic particles that are stable constituents of atomic structure?
protons, neutrons, and electrons
The presence of an appropriate enzyme affects only the ________.
rate of the reaction
The dispersed substances in a solution are called ________.
solutes
Compared with the other major organic compounds, nucleic acids are unique in that they ________.
store and process information at the molecular level
The chemical properties of every element are determined by ________.
the number and arrangement of electrons in the outer energy level
Whether an atom will react with another atom will be determined primarily by ________.
the number of electrons in the outermost energy level
Two simple sugars joined together form a disaccharide. The reaction involved requires ________.
the removal of water to create a more complex molecule
Which type of lipid is a good energy source, provides insulation, and helps protect delicate organs?
triglycerides
The ideal medium for the absorption and/or transport of inorganic or organic compounds is ________.
water