cell molec final ASF
The Na+/K+ pump actively moves
3 Na+ out, 2 K+ in.
Prokaryotes have ________S ribosomes with ________S and ________S subunits, whereas eukaryotes have ________S ribosomes with ________S and ________S subunits.
70, 50, 30; 80, 60, 40
At which enzymatic step of glycolysis is water a product?
9
Facilitated diffusion implies that energy in which form is NOT required?
ATP
Which of the following is not a tenet of the cell theory?
All cells have a membrane-bound nucleus.
Aerobic refers to what property of chemotrophs?
Chemotrophs require oxygen to produce energy.
A protein is destined to be secreted from a cell. In which organelle would you expect to find the protein just after it is produced in the rough endoplasmic reticulum?
Golgi apparatus
All of the following are model organisms, except
Homo sapiens.
Why is the Lineweaver—Burk plot important in enzyme kinetics?
It makes it easier to determine Vmax.
Why is a selectively permeable membrane so important to living things?
It provides a good barrier
Matter and energy flow through the biosphere. The flow of matter, however, differs from the flow of energy. Which of the following statements accurately describes these differences?
Matter flows in cycles, whereas energy flows in one direction.
An example of indirect active transport is
Na+/glucose symport.
Which of the following is true of purines?
Purines have a double-ringed structure.
The chemical nature of each amino acid is determined by which of the following groups?
R group
Which of the following is a heterotroph?
a mushroom
Which of the following is a phototroph?
a tree
Which of the following is closest to a micrometer in size?
a typical bacterial cell
Which of the following is not a product of the TCA cycle?
acetyl CoA
The site on an enzyme that will bind the substrate is called the
active site.
Which of the following statements accurately describes the Calvin cycle?
all of the above
Because the TCA cycle is associated with degradation and synthesis, the pathway is said to be
amphibolic.
NADP+ is the coenzyme of choice in ________ reactions, while NAD+ is the coenzyme of choice in ________ reactions.
anabolic; catabolic
The methanobacteria, halobacteria, and sulfobacteria are included in which domain?
archaea
An allosteric inhibitor
binds at the regulatory site
An enzyme
binds substrates in a manner that facilitates the formation of product.
The term amphipathic describes the characteristic of some molecules that have ________.
both a polar and non polar region
The statement, "Energy is neither created nor destroyed," describes
both choices A and C
Why do polar substances such as NaCl dissolve so readily in water?
both choices C and D
A competitive inhibitor
cannot be processed by the enzyme.
Cellulose belongs to which of the following groups of macromolecules?
carbohydrates
An energy-liberating pathway is considered to be
catabolic
The breakdown of glucose to pyruvate by a cell is an example of a(n) ________ reaction.
catabolic
In a chloroplast, the stroma is the
central semifluid region.
Which of the following organelles is not generally found in animal cells?
central vacuole
The term amphipathic refers to those molecules that are
charged at one end and nonpolar at the other.
In electron transport, which respiratory complex is not involved in the flow of electrons from FADH2?
complex I
Of the following sequences, which shows the correct molecules through which electrons flow when delivered to the electron transport system by NADH?
complex I, coenzyme Q, complex III, cytochrome c, complex IV, oxygen
In electron transport, which respiratory complex is not involved in the flow of electrons from NADH?
complex II
Which of the following is not a characteristic of DNA?
contains ribose
A spontaneous reaction
could occur but might take a very long time.
Which of the following is a terpene?
dolichol
Which type of microscopy has the greatest resolving power?
electron
Which of the following is defined as "heat content"?
enthalpy
Photoheterotrophs are best described as organisms that obtain energy to make ATP
from sunlight but cannot make organic compounds from CO2.
One mechanism by which ions are specifically transported into the cell is the
gated channel
Of the following molecules, which would not be expected to be moved across a membrane by simple diffusion?
glucose
Which of the following is not a structural polysaccharide?
glycogen
Which of the following processes would be most likely to occur in the Golgi complex?
glycosylation of proteins
Which of the following is a purine?
guanine
Which laws were formulated by Mendel?
heredity
Animals that regulate their body temperature independently of the environment are called
homeotherms
The equation AB + H2O → A + B would be catalyzed by which of the following classes of enzymes?
hydrolases
Monomers are removed from polymers by ________ reactions.
hydrolysis
Which of the following is/are true with regard to water movement in osmosis?
hypotonic → hypertonic
In eukaryotes, pyruvate is converted to acetyl CoA
in the mitochondrial matrix.
The induced-fit model
involves a conformational change in the shape of the enzyme.
β-oxidation
is a process used to oxidize fatty acids.
The primary structure of a protein
is simply the order of amino acids from one end of the protein to another. is important both genetically and structurally. is important for determining the secondary and tertiary structure of a protein. is the linear sequence of amino acids that are linked together by peptide bonds. all of the above****
The smooth endoplasmic reticulum functions in synthesis of
lipids
Which of the following is not a polymer of numerous monomer units?
lipids
Which of the following is not soluble in water?
lipids
The steps of the scientific method, in the correct order, are:
make observations, formulate the hypothesis, design experiments, collect data, interpret results, and draw conclusions.
Muscle contraction is an example of which of the following types of work?
mechanical
Which of the following types of work involves a change in position of the cell or a cell structure?
mechanical
Which of the following is a eukaryotic characteristic?
membrane-bound nucleus
All of the following are associated with substration activation except
neutron transfer.
The movement of water through a membrane, from an area of high concentration to an area of low concentration, is known as
osmosis.
As pyruvate is prepared for the TCA cycle, it undergoes a process of
oxidative decarboxylation.
Which of the following would not be used as a final electron acceptor in anaerobic respiration?
oxygen
Which of the following is not an example of facilitated diffusion?
oxygen transport
Which of the following measures is used to determine a substance's polarity?
partition coefficient
Which of the following is not one of the six classes of lipids?
pectins
The ATP synthase complex in the thylakoid membrane
performs photophosphorylation in oxygenic phototrophs.
The cell membrane can be described most accurately as
permeable to some molecules and impermeable to others
The nucleoside triphosphate molecules in DNA are linked together in the 5'→3' by a(n) ________ bridge.
phosphodiester
The process by which photosynthetic organisms use light energy for ATP production is known as
photophosphorylation.
Which of the following is not a possible noncovalent interaction?
polar covalent bonding
According to the EC system, which is not one of the major groups of enzymes?
proteases
All of the following are coenzymes except
pyruvate dehydrogenase
Membrane proteins may function in
receiving extracellular signals.
The purpose of the fermentation process is the
regeneration of NAD+
Lipid rafts are
regions of the membrane that are high in sphingolipids, which facilitate communication with the external environment of the cell.
The transfer of energy from a photoexcited electron to another electron of an adjacent pigment molecule is known as
resonance energy transfer.
Which of the following organelles is not part of the endomembrane system?
ribosome
In the Calvin cycle, the enzyme that catalyzes the capture of carbon dioxide and the formation of 3-phosphoglycerate is
ribulose bisphosphate carboxylase/oxygenase (rubisco).
The regeneration of what CO2 acceptor molecule allows for continuous carbon assimilation in the Calvin cycle?
ribulose-1,5-bisphosphate
Enzyme regulation may occur by several methods. Which of the following is not a means of enzyme regulation?
saturation
Hydrogen bonding is most important in stabilizing the ________ structure of many proteins.
secondary
The cytosol is best described as the
semifluid substance in which organelles are suspended
Carbon dioxide generally enters the plant through pores called
stomata
Disulfide bonds are often found to stabilize which of the following levels of protein structure?
tertiary
The statement, "The total amount of energy in the universe is constant," is a tenet of
the first law of thermodynamics.
Saturation can be defined as
the inability to increase reaction velocity beyond a finite upper limit.
A negative free energy change indicates that
the reaction is exothermic.
The equation A-PO4 + B → A + B-PO4 would be catalyzed by which of the following classes of enzymes?
transferases
An enzyme influences the structure of which of the following?
transition state
Which of the following is not a base used in DNA replication?
uracil
Which of the following is an important characteristic for a model organism?
widely studied
In a biochemical reaction, reactants may be converted into products. The extent to which this occurs spontaneously is expressed as which of the following?
ΔG
The sequential process of fatty acid catabolism to acetyl CoA is called
β-oxidation.