biology chapter 5
which of these is hydrophobic like the interior of the plasma membrane?
Lipid soluble molecule
Which part of the ATP molecule breaks free of the rest when an ATP molecule is used for energy?
Part D
Substrates bind to an enzyme's ________ site.
active
the movement of atoms, ions, or molecules from a region of higher concentration to regions of lower concentration is called _____.
diffusion
the diffusion of water across a selectively permeable membrane is called _____.
osmosis
Oxygen crosses a plasma membrane by
passive transport
The process of a white blood cell engulfing a bacterium is
phagocytosis
Most enzymes are
proteins
Most of the functions of a cell membrane, including transport and enzymatic function, are performed by
proteins
Enzymes work by _____.
reducing activation energy
What name is given to the reactants in an enzymatically catalyzed reaction?
substrate
When a cell uses chemical energy to perform work, it uses the energy released from a(n) ________ reaction to drive a(n) ________ reaction.
exergonic; endergonic
mechanisms such as ______________, enable precise control over a cell's ______________- all of its chemical reactions
feedback inhibition; metabolism
What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?
hydrolysis
There is a net diffusion of water out of an animal cell when it is placed in a(n) ___ solution.
hypertonic
a plant cell placed in a(n) _____ solution will lose water and plasmolyze.
hypertonic
an animal cell placed in a(n) _______ solution will gain water, swell, and possibly burst
hypotonic
A cell that has neither a net gain of water nor net loss of water when it is immersed in a solution must be
isotonic to its environment
When placed in a hypotonic environment, where the solute concentration is below that of the cell, a houseplant will _____.
remain standing upright
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
which of the following processes is endergonic?
the synthesis of glucose from carbon dioxide and water
Structure A in the figure is a(n) _____.
transport protein
Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient.
transport proteins; down
The transfer of a phosphate group to a molecule or compound is called
phosphorylation
there are three main types of cellular work: chemical, transport, and movement. most of this work is powered by the transfer of a phosphate group from one molecule to another in a process known as _____.
phosphorylation
Which figure depicts an animal cell placed in a solution hypotonic to the cell?
Cell A
Phagocytosis is to eating as pinocytosis is to
drinking
Small, nonpolar, hydrophobic molecules such as fatty acids
easily pass through a membrane's lipid bilayer.
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 of the following statements offers the most logical explanation for this action.
elevated body temperature may denature enzymes. this would interfere with the cells abilities to catalyze various reactions
What is the correct label for "A"?
energy of activation
A specific ______ speeds up each of a cell's chemical reactions.
enzyme
through energy coupling, cells use _________, or energy releasing, reactions to drive _________, or energy requiring, reactions. the molecule ________is the energy shuttle between these two types of reactions.
exergonic; endergonic; ATP
Certain cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. This enzyme is a protein. Which of the following processes could be responsible for its secretion?
exocytosis
The ideal osmotic environment for a plant cell is a(n) ___ environment.
hypotonic
in the 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. the solution in the ballon is ______ relative to the solution in the beaker.
hypotonic
An enzyme
is an organic catalyst
As a result of its involvement in a reaction, an enzyme _____.
is unchanged
A plant cell surrounded by a(n) ___ solution will be flaccid (limp).
isotonic
the ideal osmotic environment for an animal cell is a(n) ______ environment
isotonic
Anything that prevents ATP formation will most likely
result in cell death
plasma membranes are selectively permeable. this means that
the plasma membrane allows some substances to enter or leave a cell more easily than others.
which of the following is an accurate comparison of active transport and facilitated diffusion
Active transport moves solutes against their concentration gradient; facilitated diffusion moves substances down their concentration gradient.
cellular respiration is an example of ________.
an exergonic process
cells store energy that they use for work in the ________.
arrangement of atoms within molecules
Light is _____ energy, which is converted into _____ energy by plants.
kinetic ... chemical