Which one of the following is not a
function of the plasma membrane? The plasma membrane
is the control center of the cell
In lab, you use a special balloon that is
permeable to water but not sucrose to make an "artificial cell." The balloon is filled with a solution of 20% sucrose and 80% water and is immersed in a beaker containing a solution of 40% sucrose and 60% water. Which of the following will occur?
Water will leave the balloon
In the reaction A → B + C + heat,
the potential energy of the products is less than that of the reactant
When two aqueous solutions that differ
in solute concentration are placed on either side of a semipermeable membrane, and osmosis is allowed to take place, the water will
exhibit a net movement to the side with lower water concentration
Bacterial production of the enzymes
needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example of
Small, nonpolar, hydrophobic molecules
such as fatty acids
easily pass through a membrane's lipid bilayer.
A steer must eat at least 100 pounds of grain to gain less than 10 pounds of muscle tissue. This illustrates
the second law of thermodynamics.
Which of the following can affect the rate
of an enzyme-catalyzed reaction?
All of the choices are correct.
Which of the following is not a true
statement about diffusion? Diffusion
occurs when particles spread from areas where they are less concentrated to areas
where they are more concentrated
Diffusion does not require the cell to
expend ATP. Therefore, diffusion is considered a type of
The cholesterol associated with cell membranes
helps to stabilize the cell membrane at body temperature.
Kinetic energy differs from chemical
energy in that
kinetic energy is the energy of a moving object, whereas chemical energy is the potential
energy of molecules.
When physicians perform an organ
transplant, they choose a donor whose tissues match those of the recipient as closely as possible. Which of the following cell components are being matched?
The fluid mosaic model describes the
plasma membrane as consisting of
individual proteins and phospholipids that can drift in a phospholipid bilayer.
Which one of the following processes could result in the net movement of a substance into a cell, if the substance is more concentrated in the cell than in the surroundings?
Which of the following energy transfers
is/are possible in living systems?
All of the choices are correct.
What is the basic difference between
exergonic and endergonic reactions?
Exergonic reactions release energy; endergonic reactions absorb it.
If placed in tap water, an animal cell will
undergo lysis, whereas a plant cell will not. What accounts for this difference?
the relative inelasticity and strength of the plant cell wall
Plasma membranes are selectively
permeable. This means that
the plasma membrane allows some substances to enter or leave a cell more easily
Ultimately, nearly all animals are
dependent on __________ as their source of energy.
Which one of the following is a typical
feature of an ATP-driven active transport mechanism?
None of the choices are correct
A child is brought to the hospital with a
fever of 107°F. Doctors immediately order an ice bath to lower the child's temperature. Which explanation offers the most logical reason for this action?
Elevated body temperatures may denature enzymes. This would interfere with the cell's
abilities to catalyze various reactions
Glucose molecules provide energy to
power the swimming motion of sperm. In this example, the sperm are changing
chemical energy into kinetic energy
Which one of the following processes is
the synthesis of glucose from carbon dioxide and water
Which one of the following is true about
the ATP molecule?
It contains a nitrogenous base molecule called adenine
Some protozoans have special
organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment
is hypotonic to the protozoan.