BIO 121 Chapter 5 Questions
Which choice describes a laboratory technique that scientists might use to mimic a natural genetic process of cells?
directed evolution
The reaction ADP + P --> ATP is a(n) _____ reaction.
endergonic
Which of these reactions requires a net input of energy from its surroundings?
endergonic
Calories are units of __________.
energy
"Conservation of energy" refers to the fact that _____.
energy cannot be created or destroyed but can be converted from one form to another
Endocytosis moves materials _____ a cell via _____.
into ... membranous vesicles
Chemical energy is a form of _____ energy.
potential
Most enzymes are _____.
proteins
Which is a true statement about the ATP cycle?
A single muscle cell needs only about one minute to recycle all of its ATP.
Cells use this molecule to store the chemical energy released by the breakdown of food molecules during cellular respiration.
ATP
In cells, what is usually the immediate source of energy for an endergonic reaction?
ATP
When cells are placed in hypotonic solutions, both animal and plant cells accumulate water as a result of osmosis. This causes the cells to swell. Why can plant cells better tolerate hypotonic solutions?
Animal cells can burst in such situations. In plants, however, rigid cell walls limit how far cells can expand and exert a back pressure to limit further water uptake.
Which one of the following statements about energy is correct?
Energy cannot be created or destroyed.
What is the fate of the phosphate group that is removed when ATP is converted to ADP?
It is acquired by a reactant in an endergonic reaction.
What best explains the observation that enzymes are selective in the reactions they catalyze?
There is a precise compatibility between an enzyme's active site and the substrate molecule.
Which one of the following is an example of osmosis?
Water enters a plant by passing through the root cell membranes.
Which of the following is an example of potential energy?
a bowling ball placed on the top shelf of a closet
Which of these is exhibiting kinetic energy?
a space station orbiting Earth
The concentration of calcium in a cell is 0.3%. The concentration of calcium in the surrounding fluid is 0.1%. How could the cell obtain more calcium?
active transport
The use of energy to move molecules across a membrane defines __________.
active transport
Which are materials found in a molecule of ATP?
an organic molecule called adenosine plus three phosphate groups
In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?
cellular respiration
An enzyme is a protein that __________.
changes the rate of a metabolic reaction without being consumed by the reaction
Molecules of food have a form of potential energy called __________.
chemical energy
The passive movement of molecules from an area of higher concentration to an area of lower concentration is called __________.
diffusion
Activation energy can be described as __________.
energy needed to activate the reactants and trigger a chemical reaction
Every time energy is converted from one form to another, __________.
entropy increases
A(n) _____ reaction occurs spontaneously.
exergonic
The energy for an endergonic reaction comes from a(n) _____ reaction.
exergonic
The reaction A --> B + C + heat is released in a(n) _____ reaction.
exergonic
How do some inhibitors slow down metabolic pathways when the products of the pathways are not needed but still allow a pathway to proceed when the products are needed?
feedback regulation
Which of these are by-products of cellular respiration?
heat and water
What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?
hydrolysis
In osmosis, water always moves toward the __________ solution, that is, toward the solution with the __________ solute concentration.
hypertonic ... greater
An enzyme _____.
is an organic catalyst
As a result of its involvement in a reaction, an enzyme _____.
is unchanged
An animal cell placed in a hypertonic solution will __________.
lose water by osmosis and shrivel
Scientists are exploring an area of modern science called nanotechnology that involves __________.
manipulation of materials at the molecular level
Water enters a plant by passing through the root cell membranes.
osmoregulation
What name is given to the process by which water crosses a selectively permeable membrane?
osmosis
Facilitated diffusion is a type of _____.
passive transport
A white blood cell engulfing a bacterium is an example of _____.
phagocytosis
Which one of the following terms is sometimes called "cell eating"?
phagocytosis
Enzymes work by _____.
reducing activation energy
A characteristic of phospholipids that makes them a candidate for the first organic compounds on Earth to be related to life is their ability to __________.
self-assemble into simple membranes
What name is given to the reactants in an enzymatically catalyzed reaction?
substrate
Which is the best definition of energy?
the capacity to cause change
Entropy means that __________.
the quantity of usable energy declines with each energy transformation
What is energy coupling?
the use of energy released from an exergonic reaction to drive an endergonic reaction
ATP drives work in cells by __________.
transferring its phosphate group to other cell molecules
