THE TERMS RUN AND TUMBLE ARE GENERALLY ASSOCIATED WITH A) cell wall fluidity. B) cell membrane structures. C) taxic movements of the cell. D) clustering properties of certain rod-shaped bacteria. A MAJOR FUNCTION OF PROKARYOTIC GAS VESICLES IS A) to confer buoyancy on cells by decreasing their density. B) to serve as a reservoir for oxygen and carbon dioxide. C) to keep the cell's organelles separated during flagellar motion. D) none of the above. WHAT IS THE BIOLOGICAL FUNCTION OF ENDOSPORES? A) They are bacterial reproductive structures. B) They enable organisms to endure extremes of temperature, drying, and nutrient depletion. C) They are formed as evaginations of the bacterial cell walls. D) All of the above. WHEN DOES ENDOSPORE FORMATION COMMENCE? A) When bacterial growth ceases due to exhaustion of an essential nutrient. B) When the bacterium is undergoing binary fission. C) When bacteria are dividing exponentially. D) Following bacterial death. vero/falso? AS A GENERAL STATEMENT, INCLUSIONS ARE MADE UP OF STORAGE MATERIAL. SPECIES OF ARCHAEA ARE MORE CLOSELY RELATED TO EUKARYOTES THAN ARE SPECIES OF PROKARYOTES. ORGANISMS MAY RESPOND TO TEMPORAL RATHER THAN SPATIAL GRADIENTS. CELL MOVEMENT IS CLOSELY TIED TO ENERGY EXPENDITURE. CHEMOTAXIS IS A CHEMOTACTIC SENSORY RESPONSE AFFECTING FLAGELLAR FUNCTION. IN PHOTOTAXIS, PHOTOSYNTHETIC ORGANISMS MOVE AWAY FROM A LIGHT SOURCE. POLY-Β-HYDROXYBUTYRIC ACID IS A CARBON AND ENERGY STORING POLYMER. * * * * * * * THE FOCUS OF SEQUENCING EFFORTS FOR PROKARYOTIC EVOLUTIONARY STUDIES HAS BEEN ON WHICH RRNA SUBUNIT? A) 5S. B) 16S. C) 18S. D) 23S. 1
THE MOST WIDELY USED MOLECULAR CHRONOMETER IS A) DNA. B) ATPase. C) ribosomal RNA. D) cytochrome C. THE CYANOBACTERIA PROBABLY EVOLVED FROM A) anoxygenic phototrophs. B) anoxygenic lithotrophs. C) oxygenic phototrophs. D) oxygenic lithotrophs. BASED ON OUR PRESENT UNDERSTANDING, WHICH STATEMENT IS PROBABLY TRUE? A) Bacteria and Archaea diverged from a Eukarya ancestor. B) Bacteria and Eukarya evolved from an archaeal ancestor. C) Bacteria and Eukarya evolved from one line; Archaea had a totally different ancestor. D) Bacteria, Archaea, and Eukarya all diverged from a common universal ancestor or community of organisms. THE CYANOBACTERIA ARE MOST CLOSELY RELATED TO THE A) gram-negative Bacteria. B) gram-positive Bacteria. C) Archaea. D) Eukarya. PAIRED CHROMOSOMES ARE FOUND IN THE A) Bacteria. B) Eukarya. C) Archaea. D) viruses. ACCORDING TO OUR PRESENT UNDERSTANDING, MITOCHONDRIA AND CHLOROPLASTS ARE PROBABLY IN ORIGIN. A) viral B) prokaryotic C) eukaryotic D) archaeal IN MANY OF THE CHEMOLITHOTROPHIC SPECIES, SULFUR COMPOUNDS ARE TO FUEL EITHER METABOLIC FUNCTIONS OR ENERGY GENERATION. A) oxidized B) reduced C) hydrated D) neutralized HOW WAS IT DETERMINED THAT MITOCHONDRIA AND CHLOROPLASTS OF EUKARYOTES ARE ACTUALLY ANCESTORS OF SPECIFIC LINEAGES OF BACTERIA? A) Visual inspection B) Ribosomal RNA sequencing technology C) Evolutionary studies D) Clinical diagnosis 2
CONVENTIONAL TAXONOMY INCLUDES A) morphology. B) nutritional requirements. C) biochemical and environmental requirements. D) all of the above. vero/falso? THE EARLIEST NUCLEIC ACID WAS PROBABLY A SIMPLE DNA MOLECULE. DNA POLYMERASES ARE LESS PRECISE THAN RNA POLYMERASES. ACCORDING TO OUR PRESENT UNDERSTANDING, EACH OF THE MAJOR DOMAINS HAS WHAT IS KNOWN AS ITS OWN UNIVERSAL ANCESTOR MICROORGANISMS TODAY ARE MOST PROBABLY A DEGENERATION OF THE EARLIEST LIFE FORMS. ENDOSYMBIOSIS IS AN EXPLANATION FOR THE ORIGIN OF MITOCHONDRIA AND CHLOROPLASTS IN EUKARYOTIC CELLS. PHYLOGENETIC COMMUNITY ANALYSES GENERALLY SHOW A MULTITUDE OF DISTINCT ORGANISMS WHOSE RNA SEQUENCES DO NOT MATCH ANY OF THOSE IN PRESENT DATABASES. IN BOTH QUALITATIVE AND QUANTITATIVE STUDIES, THE MOST PREDOMINANT MEMBERS OF THE MICROBIAL COMMUNITY HAVE DEFIED LABORATORY CULTURE. DNA:DNA HYBRIDIZATION IS A USEFUL TAXONOMIC TOOL FOR REVEALING SUBTLE GENETIC DIFFERENCES BECAUSE IT MEASURES THE DEGREE OF SEQUENCE SIMILARITY IN TWO DNAS. BACTERIAL IDENTIFICATION CAN OFTEN BE ACCOMPLISHED THROUGH AN ANALYSIS OF THE TYPES AND PROPORTIONS OF THE FATTY ACIDS PRESENT IN THE MEMBRANE. THE METHODOLOGY EMPLOYED IS OFTEN NICKNAMED FAME. IN TAXONOMY, FAMILY IS A MORE GENERAL TERM THAN ORDER. * * * * * * * VIRAL REPLICATION IS A) independent of the cell's chromosomes but dependent on the cell itself. B) independent of both the cell's chromosomes and the cell itself (although the cell does provide a convenient matrix for replication). C) dependent on the cell's chromosomes but independent of the cell itself. D) dependent on both the cell's chromosomes and the cell itself. VIRAL REPLICATION OCCURS IN THE A) intracellular state only. B) extracellular state only. C) both the intracellular state and the extracellular state. D) either the intracellular state or the extracellular state, depending on the virus involved. 3
VIRAL SIZE IS GENERALLY MEASURED IN A) micrometers. B) picometers. C) nanometers. D) attometers. ENVELOPED VIRAL MEMBRANES ARE GENERALLY WITH ASSOCIATED VIRUS-SPECIFIC. A) lipid-bilayers / phospholipids B) protein-bilayers / lipids C) lipid-bilayers / proteins D) glycolipid-bilayers / phospholipids WHICH STATEMENT IS TRUE? A) All viruses contain their own nucleic acid polymerases. B) Some viruses contain their own nucleic acid polymerases. C) Viruses do not contain their own nucleic acid polymerases. D) The origins of the nucleic acid polymerases used by viruses are eukaryotic in nature. VIRUSES INFECTING ARE TYPICALLY THE EASIEST TO GROW IN THE LABORATORY. A) plants B) animals C) fungi D) prokaryotes RESTRICTION IS A) the viral process whereby a host's DNA ceases normal functioning. B) the viral process whereby the virus prevents other viruses from entering the cell. C) the cellular process whereby the host cell prevents the invasion of foreign nucleic acid. D) the cellular process viral particles are prevented from further infective action. A VIRUS THAT KILLS ITS HOST IS SAID TO BE A) virulent. B) temperate. C) lysogenic. D) virulent or lysogenic, but not temperate. WHICH STATEMENT IS TRUE ABOUT THE BACTERIOPHAGES? A) T2 has been studied the most extensively. B) T4 has been studied the most extensively. C) T6 has been studied the most extensively. D) T2, T4, and T6 have all been studied to about the same degree. THE PACKAGING MECHANISM OF T4 DNA INVOLVES CUTTING OF DNA FROM A) linear genetic elements. B) circular genetic elements C) DNA concatamers. D) none of these - they are all transcribed directly from inserted viral DNA. 4
A PROPHAGE REPLICATES A) along with its host as long as the lytic genes are being expressed. B) along with its host as long as the lytic genes are not being expressed. C) independent of its host as long as the lytic genes are being expressed. D) independent of its host as long as the lytic genes are not being expressed. THE VIRUS REPRESSOR PROTEIN A) controls the prophage's lytic genes but not the incoming genomes of the same virus. B) does not control the prophage's lytic genes but does control the incoming genomes of the same virus. C) controls both the prophage's lytic genes and the incoming genomes of the same virus. D) has different actions in different situations. LAMBDA IS A A) temperate phage that infects E. coli. B) linear double-stranded DNA phage. C) one of the best studied lysogenic phages. D) all of the above. VIRUSES POSSESSING WHAT TYPE OF NUCLEIC ACID ARE SUSCEPTIBLE TO DESTRUCTION BY PROKARYOTIC DNA RESTRICTION ENDONUCLEASES? A) Double-stranded DNA B) Single-stranded DNA C) Double-stranded RNA D) Single-stranded RNA WHAT IS THE HOST PROTEIN THAT CAUSES INDUCTION OF BACTERIOPHAGE LAMBDA? A) Lambda repressor B) RecA C) Cro D) Q protein WHEN A VIRUS ENTERS A HOST CELL IN WHICH IT CAN REPLICATE, THE PROCESS IS CALLED A) infection B) adsorption C) penetration D) release : AN ICOSAHEDRON HAS FACES. A) 12 B) 30 C) 20 D) 60 vero/falso? VIRUSES HAVE BOTH AN INTRACELLULAR AND AN EXTRACELLULAR FORM. VIRUSES CAN REDIRECT HOST METABOLIC FUNCTIONS. 5
IN THE FIRST FEW MINUTES AFTER HOST CELL INFECTION THE VIRUS UNDERGOES AN ECLIPSE. SOME VIRUSES ENCODE HOST RESTRICTION SYSTEMS DESIGNED TO DESTROY HOST DNA. TEMPERATE VIRUSES CAN ENTER A STATE CALLED LYSOGENY. LYSOGENY IS LIMITED TO BACTERIOPHAGES; SIMILAR RELATIONSHIPS HAVE NOT BEEN FOUND AMONGST THE ANIMAL VIRUSES. THE VIRUS REPRESSOR PROTEIN IS SAID TO GIVE IMMUNITY TO INFECTION BY THE SAME TYPE OF VIRUS. A LYTIC INFECTION RESULTS IN THE DESTRUCTION OF THE HOST CELL. 6