Test 2: Chapter 4-6
The standard state of dilute aqueous solutions is at a temperature of ________°C (298 K), ________ atmosphere(s) of pressure, and with products and reactants present in concentration of ________ mol/L.
25:1:1
Nonprotein catalysts are known as ________.
Ribozymes
The matrix is to the mitochondrion as the ________ is to the chloroplast.
Stroma
All of the following are associated with substrate activation except Select one: a. electron transfer. b. intramolecular hydrogen bonding. c. bond distortion. d. neutron transfer. e. proton transfer.
d. neutron transfer
Which of the following is not believed to be a virus or to be caused by a virus? Select one: a. Epstein-Barr b. T4 phage c. AIDS d. scrapie e. TMV
d. scrapie
Tubulin is to microtubules as ________ is to microfilaments.
Actin
A ________ is the amount of energy required to warm 1 gram of water 1 degree Celsius at 1 atmosphere of pressure.
Calorie
Membrane proteins may function in Select one: a. information storage. b. protein manufacture. c. receiving extracellular signals. d. temperature control. e. amphipathic modification.
c. receiving extracellular signals
________ are enzymes able to convert a substrate to its mirror image.
Isomerases
Which of the following is true of a lysosome? Select one: a. The lysosome may mature from a late endosome. b. all of the above c. The contents of the lysosome originate in the smooth ER. d. The lysosome functions in export packaging. e. The lysosome may function in glycosylation.
a. The lysosome may mature from a late endosome.
The site on an enzyme that will bind the substrate is called the Select one: a. active site. b. activation site. c. prosthetic group. d. metastable site. e. catalyst.
a. active site
Which process involves an increase in entropy of the system? Select one: a. combustion of paper b. synthesis of cellulose c. any spontaneous process d. freezing of ice e. formation of raindrops
a. combustion of paper
Which of the following is included as part of the Eubacteria? Select one: a. cyanobacteria b. methanogens c. thermacidophiles d. sulfobacteria e. halobacteria
a. cyanobacteria
Another name for an oxidizing agent is a(n) Select one: a. electron acceptor. b. electron donor. c. hydride transfer reagent. d. electropositive metal. e. reductant.
a. electron acceptor
A sick person often has a fever, which can inhibit the growth of bacteria because Select one: a. enzymes do not function as well at temperatures other than the optimal temperature. b. fever blocks synthesis of proteins in the bacterial nucleus. c. bacteria reproduce more rapidly at higher body temperature. d. sweating removes prosthetic groups from biological enzymes. e. the higher temperature increases the activity of lyases.
a. enzymes do not function as well at temperatures other than the optimal temperature.
An organism that is labeled a cryophile is capable of Select one: a. growth at 4°C. b. synthesizing liquid nitrogen. c. both choices C and D d. growth in hydrothermal vents. e. producing large quantities of liquid hydrogen.
a. growth at 4°C.
The induced-fit model Select one: a. involves a conformational change in the shape of the enzyme. b. proposes that very strong covalent bonds are formed upon substrate binding. c. states that enzyme-substrate interactions are rigid. d. was proposed by Hans Buchner. e. is also called the lock-and-key model.
a. involves a conformational change in the shape of the enzyme
The term "junk DNA" is no longer used because these regions of DNA have been found to be associated with all of the following except Select one: a. binding sites for regulatory regions. b. All of these have been associated with "junk DNA." c. speciation. d. miRNAs. e. None of these have been associated with "junk DNA."
b. All of these have been associated with "junk DNA."
Substrate activation may involve Select one: a. a change in enzyme conformation induced by substrate binding. b. all of the above c. donation of protons to the enzyme. d. formation of temporary covalent bonds. e. accepting protons from the enzyme.
b. all of the above
Bioenergetics can be simply defined as Select one: a. the units in which energy is expressed. b. applied thermodynamics. c. the application of biological principles to physics. d. holding constant the variables in the universe. e. a subdivision of biology.
b. applied thermodynamics
Which of the following is an example of a prosthetic group? Select one: a. a glycine residue b. a polypeptide chain c. a zinc ion d. carboxypeptidase A e. a nickel catalyst
c. a zinc ion
A competitive inhibitor Select one: a. binds to and inactivates the substrate. b. binds at a site other than the active site. c. cannot be processed by the enzyme. d. irreversibly binds and inactivates the enzyme. e. does not inhibit enzyme activity but does lower substrate concentration.
c. cannot be processed by the enzyme
A spontaneous reaction Select one: a. is associated exclusively with homeothermic organisms. b. has an overall positive free energy change. c. could occur but might take a very long time. d. has to occur immediately. e. will never occur.
c. could occur but might take a very long time
When the size of a cell increases, the surface area/volume ratio a. decreases initially and then begins to increase. b. increases initially and then begins to decrease. c. decreases. d. remains the same. e. increases.
c. decreases
Which of the following is defined as "heat content"? Select one: a. heat loss b. entropy c. enthalpy d. solar radiation e. energy output
c. enthalpy
Communication between adjacent animal cells is facilitated by Select one: a. plasmodesmata. b. tight junctions. c. gap junctions. d. desmosomes e. adhesive junctions.
c. gap junctions
Which of the following diseases is caused by a prion? Select one: a. Zellweger syndrome b. infantile Refsum disease c. mad cow disease d. Tay-Sachs disease e. polio
c. mad cow disease
Kuru is a degenerative disease of the central nervous system believed to be caused by which type of agent? Select one: a. protozoan b. bacterium c. prion d. viroid e. virus
c. prion
________ is the turnover number for a given enzyme.
KCAT
An allosteric inhibitor Select one: a. is identical to the active site. b. increases the rate of substrate binding. c. is converted to an activator by the enzyme. d. binds at the regulatory site. e. binds and activates the high-affinity state of the enzymes.
d. binds at regulatory site
The ________ is the minimum energy required before two molecules can be successful in producing a reaction.
Activation Energy
The site on an enzyme that the substrate binds to is called the ________.
Active site
________ is the partial measure of the internal energy of a system, also known as the heat content.
Enthalpy
A nonprotein component of an enzyme that is usually a metal ion or small organic molecule is called a(n) ________.
Prosthetic group
________ is a means of overcoming the activation energy barrier that depends on quantum effects.
Quantum Tunneling
Two specific coenzymes we need to obtain from our diet are niacin and ________, as our bodies cannot synthesize them.
Riboflavin
Azidothymidine (AZT) is a(n) ________ used in the treatment of AIDS and targets the enzyme reverse transcriptase.
Substrate analogue
The active site for carboxypeptidase Select one: a. involves only 6 out of a total of 307 amino acids. b. is formed by the interaction of two polypeptide chains. c. uses iron as the prosthetic group. d. contains amino acids that are contiguous to one another along the primary sequence of the protein. e. contains a glutamate residue at position 69.
a. involves only 6 out of a total of 307 amino acids
An example of an irreversible inhibitor is Select one: a. penicillin. b. isoleucine. c. a competitive inhibitor. d. a noncompetitive inhibitor. e. acetylcholinesterase.
a. penicillin
Which of the following is/are means whereby a catalyst can lower the activation energy of a reaction? Select one: a. quantum tunneling b. decreasing the number of reactive molecules c. permanently binding substrates d. inefficient collisions e. altering the temperature within the cell to one appropriate for reactions to proceed
a. quantum tunneling
Of the following, which is used to inhibit specific enzymes in the treatment of many bacterial and viral diseases? Select one: a. substrate analogues b. nitrous oxide c. X-rays d. intercalating agents e. noncompetitive inhibitors
a. substrate analogues
An enzyme influences the structure of which of the following? Select one: a. transition state b. intermediate c. product d. substrate e. cofactor
a. transition state
As new enzymes are discovered, the EC system for naming enzymes is to be used. The names are to be based on which of the following criteria? Select one: a. a description of substrate function b. the six major classes of enzyme function c. the size of the enzyme d. an indication of the size of the substrate e. the name of the substrate
b. the six major classes of enzyme function
Which of the following is not generally associated with a chloroplast? a. intermembrane space b. grana c. stroma d. matrix e. thylakoids
d. matrix
The statement, "The total amount of energy in the universe is constant," is a tenet of Select one: a. enthalpy. b. the second law of thermodynamics. c. thermodynamic spontaneity. d. the first law of thermodynamics. e. entropy.
d. the first law of thermodynamics
All of the following are examples of ribozymes or ribozyme activity except Select one: a. autocatalytic RNAs. b. peptidyl transferase. c. ribonuclease P. d. zymogen. e. intron removal from pre-rRNA.
d. zymogen
Which of the following is an enzyme? Select one: a. N-acetylmuramic acid b. ATP c. iron d. histidine e. carboxypeptidase A
e. carboxypeptidase A
The type of inhibitor that binds to the enzyme (E) but not to the enzyme-substrate (ES) complex is a(n) ________ inhibitor. Select one: a. mixed-type b. noncompetitive c. coenzyme d. uncompetitive e. competitive
e. competitive
All of the following are examples of irreversible enzyme inhibitors except Select one: a. pesticides. b. aspirin. c. herbicides. d. natural poisons. e. monoamine oxidase inhibitors.
e. monoamine oxidase inhibitors
According to the EC system, which is not one of the major groups of enzymes? Select one: a. ligases b. transferases c. oxidoreductases d. hydrolases e. proteases
e. proteases
Enzyme regulation may occur by several methods. Which of the following is not a means of enzyme regulation? Select one: a. allosteric regulation b. substrate-level phosphorylation c. feedback inhibition d. covalent modification e. saturation
e. saturation
Saturation can be defined as Select one: a. the substrate concentration at which velocity reaches one-half maximum velocity. b. inhibition of enzyme function by blocking the active site. c. a characteristic of all uncatalyzed reactions. d. denaturation of an enzyme. e. the inability to increase reaction velocity beyond a finite upper limit.
e. the inability to increase reaction velocity beyond a finite upper limit.
________ are a class of enzymes responsible for the movement of functional groups from one molecule to another.
Transferases
The work of James B. Sumner was to Select one: a. originate the term ferments to describe enzymes. b. crystallize urease, the first enzyme isolated. c. isolate the insulin hormone. d. discover ribozymes. e. prove that enzymes were carbohydrates.
b. crystallize ureases, the first enzyme isolated
Covalent modification Select one: a. produces modifications that can sometimes be reversed. b. is represented by all of these c. can involve the addition of phosphate groups. d. can activate an enzyme. e. affects the activity of an enzyme by adding or removing a chemical group.
b. is represented by all of these
________ inhibitors bind reversibly at the active site of an enzyme.
Competitive
A spontaneous reaction releases energy. This type of reaction is ________.
Exergonic
Any process that results in a decrease in the free energy of the system is called ________.
Exergonic
The ________ velocity of an enzymatic reaction is the velocity at very high substrate concentration.
Maximum
________ inhibitors bind the enzyme at a location other than the active site but still interfere with product formation.
Noncompetitive
An enzyme Select one: a. binds substrates in a manner that facilitates the formation of product. b. is always a protein. c. does not change the rate at which the equilibrium is achieved. d. decreases the rate of a reaction. e. changes the position of the equilibrium of the reaction.
a. binds a substrate in a manner that facilitates the formation of product
Which of the following is not true of the enzyme-substrate interaction? Select one: a. Carboxypeptidase recognizes any of the amino acids from the carboxyl end of a polypeptide. b. Cells are often able to carry out metabolic activity with only a handful of enzymes. c. Some enzymes accept any of a whole group of substrates. d. Many enzymes are extremely specific regarding a substrate. e. Many enzymes cannot recognize a stereoisomer of their substrate.
b. cells are often able to carry out metabolic activity with only a handful of enzymes
An enzyme is active in the stomach of an animal but quickly loses its activity when it leaves the stomach. This example illustrates that enzymes are Select one: a. inactivated by movement. b. consumed by the quantities of substrate in the small intestine. c. sensitive to changes in pH. d. inactivated by inhibitors in the small intestine. e. specific to the organs in which they are produced.
c. sensitive to changes in pH
Which of the following best describes a metastable state? Select one: a. The metastable state is formed by transient complexes with the substrate. b. This state is composed of the difference in activation energy of a catalyzed versus an uncatalyzed reaction. c. The metastable state is created by the prosthetic group of the enzyme. d. The metastable state is a state of the substrate in which the reaction can proceed but typically requires a catalyst. e. This state changes the position of the equilibrium but not the rate.
d. the metastable state of the substrate in which the reaction can proceed but typically requires a catalyst
Collagen fibers are to the extracellular matrix as ________ is to the cell wall.
Cellulose
A ________ is an organism that requires the intake of chemical compounds such as carbohydrates, fats, and proteins.
Chemotroph
The ________ is comprised of the semifluid portion of the cell and contains the organelles.
Cytoplasm
Any process that results in an increase in the free energy of the system is called ________.
Endergonic
The similarity of mitochondria and chloroplasts to bacterial cells led to the development of the ________, which proposes that these organelles are derived from bacteria.
Endosymbiont theory
The melting of ice is an example of a(n) ________ process.
Endothermic
The region within the prokaryotic cell where the DNA is located is known as the ________.
Nucleoid
________ is the transfer of energy from one place or form to another place or form.
Work
Oxidation of methane Select one: a. involves the addition of oxygen atoms and the release of energy b. involves the addition of oxygen atoms and requires an input of energy c. is endothermic. d. is the gain of electrons e. involves the removal of oxygen atoms.
a. involves the addition of oxygen atoms and the release of energy
Which of the following is least likely to be part of a cell membrane? Select one: a. proteoglycans b. phospholipids c. transport proteins d. enzymes e. glycoproteins
a. proteoglycans
The statement, "Energy is neither created nor destroyed," describes Select one: a. the law of conservation of energy. b. Entropy c. enthalpy. d. the second law of thermodynamics. e. The law of segregation
a. the law of conservation of energy
A negative free energy change indicates that Select one: a. the reaction is exothermic. b. energy must be added to the reaction before it can proceed. c. the reactant is predominant at equilibrium. d. the reaction is not possible. e. the reaction is at equilibrium.
a. the reaction is exothermic
In a chemical reaction, the standard free energy change (ΔG°') is calculated to be 3.67 cal/mol. What can be said of the chemical reaction? Select one: a. The reaction is not spontaneous under standard conditions. b. Products predominate over reactants at equilibrium under standard conditions. c. The reaction is at equilibrium under standard conditions. d. There can be no reaction. e. The reaction goes spontaneously to the right under standard conditions.
a. the reaction is not spontaneous under standard conditions
With regard to tight junctions, Select one: a. they block the movement of basolateral integral membrane proteins to the apical surface. b. they are responsible for holding cardiac muscle together. c. one face of the cell, the apical surface, is in contact with other cells. d. they allow free movement of ions and molecules between cells. e. they are composed of special proteins called connexins.
a. they block the movement of basolateral integral membrane proteins to the apical surface.
In which of the following properties are the Archaea more like eukaryotes than the bacteria? Select one: a. translation initiation b. size c. microtubules and microfilaments d. both choices C and D e. mode of cell division
a. translation initiation
The hallmark feature of peroxisomal diseases is the presence of Select one: a. very long chain fatty acids. b. amyloid plaques. c. an abundance of myelin. d. long chain gangliosides. e. hydrolases.
a. very long chain fatty acids
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? a. secretory vesicle b. Golgi apparatus c. endosome d. nucleus e. lysosome
b. Golgi apparatus
When ΔG' = 0 in a chemical reaction, under standard conditions, Select one: a. the reaction is spontaneous to the left. b. reactants and products are at equilibrium. c. work can be done; no energy is required. d. work can be done; energy is required. e. the reaction is spontaneous to the right
b. reactants and products are at equilibrium
All of the following are used as bioluminescent tools for cell biologists except Select one: a. YFP. b. rhodopsin. c. GFP. d. luciferase. e. none of these
b. rhodopsin
The cytosol is best described as the Select one: a. fluid within the nucleus. b. semifluid substance in which organelles are suspended. c. three-dimensional array of interconnected filaments. d. internal contents of organelles. e. area of the cell not occupied by the nucleus.
b. semifluid substance in which organelles are suspended.
Lignin is an important component in Select one: a. plasmodesmata. b. fungal cell walls. c. plant cell walls. d. bacterial cell walls. e. tight junctions.
c. plant cell walls
When the ΔG°' of a chemical reaction is positive (K'eq < 1.0) under standard conditions, Select one: a. work can be done under these conditions. b. reactants and products are at equilibrium. c. reactants predominate over products. d. the reaction is exothermic. e. the reaction is spontaneous to the right.
c. reactants predominate over products
The steady state so vital to life is possible because Select one: a. all reactions are exothermic. b. the cell cannot convert energy from one form to another. c. the cell continually takes up energy from the environment. d. all reactions are at equilibrium. e. all cells are autotrophic.
c. the cell continually takes up energy from the environment
The size range of most plant and animal cells is ________. Select one: a. 0.1—0.5 mm b. 50—100 mm c. 1—5 μm d. 10—50 μm e. 1—10 nm
d. 10—50 μm
Prokaryotes have ________S ribosomes with ________S and ________S subunits, whereas eukaryotes have ________S ribosomes with ________S and ________S subunits. Select one: a. 80, 60, 40; 70, 50, 30 b. 100, 60, 50; 90, 60, 40 c. 70, 40, 30; 80, 50, 30 d. 70, 50, 30; 80, 60, 40 e. 80, 50, 30; 100, 60, 40
d. 70, 50, 30; 80, 60, 40
Which of the following would be attributed to a peroxisomal dysfunction? Select one: a. accumulation of glucocerebroside b. accumulation of ganglioside GM2 c. accumulation of N-acetylglucosamine phosphotransferase d. accumulation of very long chain fatty acids e. accumulation of complex sugars
d. accumulation of very long chain fatty acids
The voodoo lily (Sauromatum guttatum) is able to Select one: a. be pollinated by flies. b. emit a foul odor to attract pollinators. c. trick the pollinators into thinking it is rotting meat. d. all of the above e. utilize metabolic heat.
d. all of the above
If the surface area of a cell increases by a factor of 100, the volume of that cell will Select one: a. increase by a factor of 100. b. increase by a factor of 10. c. decrease by a factor of 100. d. increase by a factor of 1000. e. remain the same.
d. increase by a factor of 1000
Which is true of heterotrophs? Select one: a. They cannot be unicellular. b. They can function as autotrophs in an emergency. c. They store energy in the form of heat. d. They can obtain energy from consuming phototrophs. e. They capture light energy.
d. they can obtain energy from consuming phototrophs
Viroids are characterized by all of the following except Select one: a. associated with plant diseases. b. circular RNA. c. self-replicating. d. well-characterized transmission. e. latent forms exist in some genomes.
d. well-characterized transmission
In a biochemical reaction, reactants may be converted into products. The extent to which this occurs spontaneously is expressed as which of the following? Select one: a. Keq b. temperature c. TΔS d. ΔG e. ΔS
d. ΔG
Which of the following is not a basic need of the cell? Select one: a. information b. energy c. molecular building blocks d. chemical catalysts e. 100% efficiency
e. 100% efficiency
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? Select one: a. Energy flows from chemotrophs to phototrophs, whereas matter flows from phototrophs to chemotrophs. b. Matter does not accompany energy as it enters the biosphere, but it does flow with energy from the biosphere. c. Matter and energy flow sometimes in cycles and sometimes unidirectionally. d. Energy flows as organic molecules are reduced to inorganic molecules, but matter does not. e. Matter flows in cycles, whereas energy flows in one direction.
e. Matter flows in cycles, whereas energy flows in one direction
Which of the following is a heterotroph? Select one: a. grass b. a tree c. a cyanobacterium d. a geranium e. a mushroom
e. a mushroom
Which of the following is a phototroph? Select one: a. a person b. a mushroom c. an earthworm d. bacteria growing on decomposing matter e. a tree
e. a tree
Photosynthesis is to the chloroplast as ________ is to the mitochondrion.
ATP synthesis
The ________ are prokaryotes that resemble bacteria in size and cell division but are more similar to eukaryotes in DNA replication, transcription, RNA processing, and protein synthesis.
Archaea
In any physical or chemical change, energy cannot be created or destroyed. This is the ________ law of thermodynamics.
First
The pathway that a secretory protein takes from inside to outside is:
Rough ER to ER Vesicle to Golgi Complex to a Secretory Vesicle
In any physical or chemical change, the universe tends toward greater disorder. This is the ________ law of thermodynamics, or the law of thermodynamic ________.
Second; Spontaneity
The total energy stored within a system is called the ________.
Internal Energy
________ reactions release energy when electrons are removed from a substance.
Oxidation
________ are infectious proteins that are responsible for several animal diseases, including scrapie and mad cow disease.
Prions
________ reactions require an input of energy when electrons are gained, such as in the conversion CO2 → CH4.
Reduction
As a cell increases in size, volume increases faster than surface area because surface area is proportional to the ________ of the linear dimension of the cell, but volume is proportional to the ________ of the linear dimension.
Square, cube
Ribosomal subunits are referred to by number and letter combinations (e.g., 70S). The "S" refers to ________.
Svedberg Units
________ are infectious RNAs that are responsible for diseases in several crop plants, such as tobacco.
Viroid's
Aerobic refers to what property of chemotrophs? Select one: a. Chemotrophs require oxygen to produce energy. b. Fermentation releases great amounts of gas but only in chemotrophs. c. Chemotrophs use, but do not require oxygen. d. Chemotrophs remove carbon dioxide from the air. e. Heat losses occur in the presence of oxygen.
a. Chemotrophs require oxygen to produce energy
The methanobacteria, halobacteria, and sulfobacteria are included in which domain? Select one: a. eubacteria b. archaea c. blue-green algae d. all of the above e. protista
b. archaea
Which of the following organelles is not generally found in animal cells? Select one: a. endoplasmic reticulum b. central vacuole c. food vacuole d. mitochondrion e. centriole
b. central vacuole
The form of energy that is available to living organisms is in the form of Select one: a. heat. b. chemical bonds. c. sunlight. d. radiation. e. nuclear energy.
b. chemical bonds
Nerve impulses travel along the neurons by the opening of channels that allow sodium ions to flow inward, followed by an outward flow of potassium ions. In order to ensure that the impulse may be produced at any time, sodium is actively transported out of the cell, and potassium is transported into the cell by the sodium/potassium pump. Which of the following types of work is performed by the sodium/potassium pump? Select one: a. bioluminescent b. concentration c. mechanical d. electrical e. synthetic
b. concentration
Intermediate filaments are Select one: a. composed of globular proteins only. b. different in different cell types. c. the same in all cells d. smaller than actin filaments. e. composed of tubulin.
b. different in different cell types
Which of the following processes would be most likely to occur in the Golgi complex? Select one: a. detoxification of drugs b. glycosylation of proteins c. synthesis of DNA d. production and packaging of lipids e. synthesis of steroids
b. glycosylation of proteins
Which of the following is not true of a viroid? Select one: a. Cadang-cadang is a viroid disease of the coconut palm. b. Its capsid is quite small. c. Viroids affect mostly plants. d. Its RNA is circular. e. Viroids possess about 250—400 nucleotides.
b. its capsid is quite small
The smooth endoplasmic reticulum functions in synthesis of Select one: a. proteins. b. lipids. c. all of the above d. polysaccharides. e. DNA.
b. lipids
Muscle contraction is an example of which of the following types of work? Select one: a. bioluminescent b. mechanical c. concentration d. heat e. electrical
b. mechanical
Which of the following types of work involves a change in position of the cell or a cell structure? Select one: a. synthetic b. mechanical c. bioluminescent d. electrical e. concentration
b. mechanical
The major structural elements of the cytoskeleton are Select one: a. the extracellular matrix and the cell wall. b. microtubules, microfilaments, and intermediate filaments. c. cleavage furrows and G-actin. d. the cytoplasm and cytosol. e. proteoglycans and cellulose microfibrils.
b. microtubules, microfilaments, and intermediate filaments.
Glyoxysomes play an important role in the germination of fat-storing seeds and are considered to be specialized ________. Select one: a. vacuoles b. peroxisomes c. ribosomes d. centrioles e. lysosomes
b. peroxisomes
Fireflies have the ability to convert the energy in ATP to light. Which of the following types of work is performed by the firefly? Select one: a. concentration b. electrical c. bioluminescent d. heat e. mechanical
c. bioluminescent
Which of the following fundamental properties of life do viruses possess? Select one: a. cellularity b. metabolism c. evolutionary adaptation d. ability to reproduce e. homeostasis
c. evolutionary adaptation
A(n) ________ is composed of tetrameric protofilaments. Select one: a. microtubule b. microfilament c. intermediate filament d. extracellular matrix e. bacteriophage
c. intermediate filament
Under the conditions of a given reaction, a positive ΔG' means Select one: a. work can be done. b. the reaction is spontaneous. c. the reaction will not occur. d. no energy needs to be added. e. the reaction is at equilibrium.
c. the reaction will not occur
Which is not true of phototrophs? Select one: a. They can be bacteria. b. They store energy as glucose. c. They never function as autotrophs. d. They capture light energy. e. They provide energy for chemotrophs.
c. they never function as autotrophs
Which of the following diseases is caused by a peroxisomal defect? Select one: a. Tay-Sachs disease b. I-cell disease c. hypertrophic cardiomyopathy d. Zellweger syndrome e. sickle-cell anemia
d. Zellweger syndrome
Reduction involves the Select one: a. loss of neutrons. b. all of these c. increase in oxidation state. d. loss of electrons e. gain of electrons.
e. gain of electrons
Animals that regulate their body temperature independently of the environment are called Select one: a. abiotherms. b. poikilotherms. c. biotherms. d. heterotherms. e. homeotherms.
e. homeotherms
Which of the following is a eukaryotic characteristic? Select one: a. cell fission b. little processing of RNA c. none of the above d. 70S ribosomes e. membrane-bounded nucleus
e. membrane-bounded nucleus
Which of the following is an endothermic process? Select one: a. combustion reactions b. adding a strong acid directly to water c. ice melting d. neutralization reactions of the addition of strong acid directly to a strong base e. oxidation of metals
e. oxidation of metals
Which organelle has only a single membrane around it? Select one: a. mitochondrion b. chloroplast c. ribosome d. nucleus e. peroxisome
e. peroxisome
Which of the following is true of plant cells? Select one: a. Chromosomes are found only in plant cells. b. Plant cells are always much larger than animal cells. c. Only plant cells have a cell membrane. d. The plant cell has no cell wall. e. Plant cells may contain chloroplasts.
e. plant cells may contain chloroplasts
The chromoplast is an organelle associated with Select one: a. oxidation of sugars. b. storage of chromium. c. ribosome production in primitive plants. d. synthesis of secretory proteins. e. plant pigment storage.
e. plant pigment storage
Which of the following organelles is not part of the endomembrane system? Select one: a. secretory vesicle b. lysosome c. Golgi apparatus d. endoplasmic reticulum e. ribosome
e. ribosome
Which sequence reflects the locations that a secretory protein will visit on its way from its production to its secretion outside the cell? Select one: a. rough ER, secretory vesicle, Golgi complex, ER vesicle b. smooth ER, rough ER, Golgi complex, secretory vesicle c. rough ER, Golgi complex, smooth ER, ER vesicle d. nucleus, Golgi complex, rough or smooth ER, secretory vesicle e. rough ER, ER vesicle, Golgi complex, secretory vesicle
e. rough ER, ER vesicle, Golgi complex, secretory vesicle
Mitochondrial DNA is/are Select one: a. All of these are correct b. associated with paternal inheritance patterns. c. information storage for enzymes associated with photorespiration. d. similar to nuclear DNA sequences. e. used to trace dispersal of modern humans.
e. used to trace dispersal of modern humans.
Photosynthesis is an important process that Select one: a. only plants can perform. b. is performed by heterotrophs. c. is performed by organisms living near deep-ocean thermal vents. d. produces oxidized products. e. uses water and carbon dioxide as reactants.
e. uses water and carbon dioxide as reactants