Test Bank - The Cell: A Molecular
Approach
RNA - ANSWERSBelieved to have been the original genetic system because it can catalyze the
polymerization of nucleotides into another RNA strand.
Membrane-enclosing RNA molecules - ANSWERSInitially important because they maintained these
molecules as a unit capable of reproduction and evolution.
Stanley Miller's experiment - ANSWERSShowed that under a reducing atmosphere of methane,
ammonia, water, and hydrogen, amino acids can form.
First energy-producing process in cellular evolution - ANSWERSThought to be glycolysis.
Earth's atmosphere at the time life arose - ANSWERSContained abundant amounts of H2, N2, H2S,
but not O2.
Organisms using H2O in photosynthesis - ANSWERSRadically changed Earth by producing O2.
Distinguishing feature of eukaryotes - ANSWERSThe presence of a nucleus in eukaryotic cells.
Cytoplasmic organelles - ANSWERSAbsent in prokaryotic cells and present in eukaryotic cells.
Eukaryotic nucleus - ANSWERSContains multiple linear DNA molecules.
Bacterial genome location - ANSWERSLocated in a portion of the cell called the nucleoid.
Eukaryotic cell nuclei genes - ANSWERSPartly archaebacterial and partly bacterial in origin.
Origin of mitochondria and chloroplasts - ANSWERSThought to have originated in eukaryotic cells via
a process called endosymbiosis.
,Mitochondria and chloroplasts - ANSWERSResemble bacteria in that they have their own DNA,
ribosomes, and reproduce by simple division into two.
Colonial organism related to plants - ANSWERSVolvox is closely related to the evolutionary
precursors of present-day plants.
Types of cells in the human body - ANSWERSComposed of more than 200 different types of cells.
E. coli as a model system - ANSWERSUseful for molecular biology studies because it has a small
genome, reproduces rapidly, and mutants can easily be isolated from culture dishes.
Yeast cell division time - ANSWERSA yeast cell divides in culture about every 2 hours.
Haploid yeast nuclear genome - ANSWERSContains 6,000 genes.
Caenorhabditis elegans - ANSWERSConsists of 959 somatic cells.
Simplicity and clarity of Caenorhabditis elegans - ANSWERSAllowed researchers to trace the
developmental lineages of all cells in the adult.
Drosophila melanogaster - ANSWERSAn organism of choice for the study of the process of
development.
Model organism for animal body plan development - ANSWERSDrosophila melanogaster led to the
initial discovery of important mechanisms.
Arabidopsis thaliana - ANSWERSA model organism for studying the molecular biology of plants.
Useful model organism for vertebrate development - ANSWERSZebrafish.
Cultures grown from dissociated tissue cells - ANSWERSCalled primary cell cultures.
Cultured cells in laboratories - ANSWERSProvide a continuous and uniform source of new cells.
,Viruses as model systems - ANSWERSUseful for studying DNA replication.
Light microscope observation of cork - ANSWERSPerformed by Hooke, who named the chambers
'cells.'
Diffraction limited resolution equation - ANSWERSR = 0.61λ / NA.
Diffraction limited resolving power of a standard light microscope - ANSWERSApproximately 0.2 μm.
Living cells visualization - ANSWERSCommonly done by phase-contrast microscopy.
Fluorescent-labeled antibodies - ANSWERSUsed primarily to locate a specific protein.
Green fluorescent protein (GFP) - ANSWERSCommonly used to visualize proteins in living cells.
Experimental approach for studying protein-protein interactions - ANSWERSFluorescence resonance
energy transfer (FRET).
Recovery time in fluorescence photobleaching experiments - ANSWERSDefined as the amount of
time it takes the bleached area to regain its fluorescence.
GFP - ANSWERSA protein used to study proteins in living cells.
Super-resolution light microscopes - ANSWERSExtend the resolution limits of light microscopy to 20
to 100 nm.
Electron microscopes - ANSWERSHave a resolution advantage over light microscopes because the
wavelength of electrons is shorter than that of light.
Transmission electron microscope - ANSWERSSpecific proteins can be localized by use of gold-
labeled antibodies.
, Differential centrifugation - ANSWERSThe method by which cell components are separated by
centrifugation at progressively higher speeds.
First pellet in differential centrifugation - ANSWERSConcentrates nuclei.
Original cell - ANSWERSBelieved to have enclosed a self-replicating RNA molecule.
Source of electrons in photosynthesis - ANSWERSWater.
Major groups of prokaryotic cells - ANSWERSArchaebacteria and bacteria.
DNA in a bacterium - ANSWERSLocated in a region termed the nucleoid.
Cell lineage of plants - ANSWERSAcquired mitochondria before acquiring chloroplasts.
Amoeba Dictyostelium discoideum - ANSWERSExists as a unicellular organism in abundant nutrient
conditions and forms multicellular fruiting bodies in starvation conditions.
Epithelial cells - ANSWERSCover the surface of internal organs in the body, such as the intestine.
Yeast and E. coli - ANSWERSUsed for many fundamental molecular genetics experiments due to
short generation time.
Common model system for mammals - ANSWERSMice.
Common model for plants - ANSWERSArabidopsis thaliana.
Model systems like C. elegans and D. melanogaster - ANSWERSUseful for studying problems in cell
differentiation and developmental biology because they are multicellular systems.
HeLa cells - ANSWERSThe most commonly used cell line derived from a biopsy of a tumor carried by
Henrietta Lacks.
Approach
RNA - ANSWERSBelieved to have been the original genetic system because it can catalyze the
polymerization of nucleotides into another RNA strand.
Membrane-enclosing RNA molecules - ANSWERSInitially important because they maintained these
molecules as a unit capable of reproduction and evolution.
Stanley Miller's experiment - ANSWERSShowed that under a reducing atmosphere of methane,
ammonia, water, and hydrogen, amino acids can form.
First energy-producing process in cellular evolution - ANSWERSThought to be glycolysis.
Earth's atmosphere at the time life arose - ANSWERSContained abundant amounts of H2, N2, H2S,
but not O2.
Organisms using H2O in photosynthesis - ANSWERSRadically changed Earth by producing O2.
Distinguishing feature of eukaryotes - ANSWERSThe presence of a nucleus in eukaryotic cells.
Cytoplasmic organelles - ANSWERSAbsent in prokaryotic cells and present in eukaryotic cells.
Eukaryotic nucleus - ANSWERSContains multiple linear DNA molecules.
Bacterial genome location - ANSWERSLocated in a portion of the cell called the nucleoid.
Eukaryotic cell nuclei genes - ANSWERSPartly archaebacterial and partly bacterial in origin.
Origin of mitochondria and chloroplasts - ANSWERSThought to have originated in eukaryotic cells via
a process called endosymbiosis.
,Mitochondria and chloroplasts - ANSWERSResemble bacteria in that they have their own DNA,
ribosomes, and reproduce by simple division into two.
Colonial organism related to plants - ANSWERSVolvox is closely related to the evolutionary
precursors of present-day plants.
Types of cells in the human body - ANSWERSComposed of more than 200 different types of cells.
E. coli as a model system - ANSWERSUseful for molecular biology studies because it has a small
genome, reproduces rapidly, and mutants can easily be isolated from culture dishes.
Yeast cell division time - ANSWERSA yeast cell divides in culture about every 2 hours.
Haploid yeast nuclear genome - ANSWERSContains 6,000 genes.
Caenorhabditis elegans - ANSWERSConsists of 959 somatic cells.
Simplicity and clarity of Caenorhabditis elegans - ANSWERSAllowed researchers to trace the
developmental lineages of all cells in the adult.
Drosophila melanogaster - ANSWERSAn organism of choice for the study of the process of
development.
Model organism for animal body plan development - ANSWERSDrosophila melanogaster led to the
initial discovery of important mechanisms.
Arabidopsis thaliana - ANSWERSA model organism for studying the molecular biology of plants.
Useful model organism for vertebrate development - ANSWERSZebrafish.
Cultures grown from dissociated tissue cells - ANSWERSCalled primary cell cultures.
Cultured cells in laboratories - ANSWERSProvide a continuous and uniform source of new cells.
,Viruses as model systems - ANSWERSUseful for studying DNA replication.
Light microscope observation of cork - ANSWERSPerformed by Hooke, who named the chambers
'cells.'
Diffraction limited resolution equation - ANSWERSR = 0.61λ / NA.
Diffraction limited resolving power of a standard light microscope - ANSWERSApproximately 0.2 μm.
Living cells visualization - ANSWERSCommonly done by phase-contrast microscopy.
Fluorescent-labeled antibodies - ANSWERSUsed primarily to locate a specific protein.
Green fluorescent protein (GFP) - ANSWERSCommonly used to visualize proteins in living cells.
Experimental approach for studying protein-protein interactions - ANSWERSFluorescence resonance
energy transfer (FRET).
Recovery time in fluorescence photobleaching experiments - ANSWERSDefined as the amount of
time it takes the bleached area to regain its fluorescence.
GFP - ANSWERSA protein used to study proteins in living cells.
Super-resolution light microscopes - ANSWERSExtend the resolution limits of light microscopy to 20
to 100 nm.
Electron microscopes - ANSWERSHave a resolution advantage over light microscopes because the
wavelength of electrons is shorter than that of light.
Transmission electron microscope - ANSWERSSpecific proteins can be localized by use of gold-
labeled antibodies.
, Differential centrifugation - ANSWERSThe method by which cell components are separated by
centrifugation at progressively higher speeds.
First pellet in differential centrifugation - ANSWERSConcentrates nuclei.
Original cell - ANSWERSBelieved to have enclosed a self-replicating RNA molecule.
Source of electrons in photosynthesis - ANSWERSWater.
Major groups of prokaryotic cells - ANSWERSArchaebacteria and bacteria.
DNA in a bacterium - ANSWERSLocated in a region termed the nucleoid.
Cell lineage of plants - ANSWERSAcquired mitochondria before acquiring chloroplasts.
Amoeba Dictyostelium discoideum - ANSWERSExists as a unicellular organism in abundant nutrient
conditions and forms multicellular fruiting bodies in starvation conditions.
Epithelial cells - ANSWERSCover the surface of internal organs in the body, such as the intestine.
Yeast and E. coli - ANSWERSUsed for many fundamental molecular genetics experiments due to
short generation time.
Common model system for mammals - ANSWERSMice.
Common model for plants - ANSWERSArabidopsis thaliana.
Model systems like C. elegans and D. melanogaster - ANSWERSUseful for studying problems in cell
differentiation and developmental biology because they are multicellular systems.
HeLa cells - ANSWERSThe most commonly used cell line derived from a biopsy of a tumor carried by
Henrietta Lacks.
