Chapter 2 Homework 1 Although bacteria do not have membrane bound organelles in their cytoplasm they do have inclusion bodies such as polyhydroxybutyrate PHB and sulfur granules Why would bacteria want to store these compounds a These compounds are useful forms of energy 2 In bacterial cells you are likely to find which of the following molecules closely associated with the nucleoid of the cell a DNA polymerase RNA polymerase and RNA 3 The fact that the MreB protein is nearly always found in non spherical bacteria but rarely in cocci suggests a MreB is necessary for non cocciness MreB is a major shape determining protein cocci is the default shape in bacteria 4 Given the role microtubules play during eukaryal cell division it should come as no surprise that a critical first step in bacterial cell division id a The formation of the Z ring by tubulin like FtsZ proteins 5 The location of the Z ring in dividing bacteria is critical because It ensures the two daughter cells will be of equal volume a 6 The existence of Mycoplasmas a group of small bacteria with no cell walls suggests a Both cell walls are not a necessary condition for survival in bacteria and these organisms may occur in environments where the cell wall is not necessary 7 The ability of bacteria to consistently and repeatedly move toward an attractant and away from a repellant is evidence that a Both a mechanism exists for bacteria to alter intercellular processes in response to external stimuli and bacteria are able to discriminate between attractants and repellants 8 The difference between the taxonomic designations of strains and species is a A single bacterial species can be composed of multiple bacterial strains 9 Bacteria that exhibit highly variable shapes are said to be polymorphic 10 Carboxysomes are the bacterial precursor to chloroplasts 11 Most archaea contain FtsZ and MreB like proteins suggesting cell morphology in archaea is likely determined similarly to bacteria 12 Both gram positive and gram negative flagella are composed from subunits of flagellin 13 Classification arranges species into categories while phylogeny attempts to reflect the evolutionary relationships among species a False a False a True a True a True 14 The general size ranges of bacteria are between a 0 5 m and 5 m 15 The nucleoid is a a Large mass in the cell cytoplasm comprising the bacterial chromosome coated with various proteins and RNA molecules undergoing synthesis It is not bounded by its own membrane 16 The cytoplasm of bacterial cells contains additional components They include a Proteins many which are enzymes that carry out metabolic functions or severe structural purposes mRNA ribosomes and tRNA 17 Inclusion bodies are a Large granules that serve as storage of particular nutrients e g carbon nitrogen phosphorus 18 Of the following which one is NOT true of the bacterial plasma membrane a The polar head of the plasma membrane is hydrophobic 19 Chemotaxis involves the use of chemoreceptors and flagella The process involves chemoreceptors a Sensing certain attractants or repellants becoming activated and communicating with flagella via cytoplasmic proteins to control whether the flagella should continue to propel the bacteria forward or to reverse direction and cause tumbling instead 20 The difference between gliding motility and actin based motility is that a Gliding motility occurs when bacteria move smoothly over a surface without flagella and actin based motility involves invasion of eukaryotic cell breaking out of the vacuole into the host cell s cytoplasm and polymerization of eukaryotic actin at one cell pole to generate enough force to shoot the bacteria into a neighboring host cell 21 Pili and fimbriae are both surface appendages but pili are involved in and fimbriae are involved in 22 Biofilms are a Conjugal transfer of DNA adhesion 23 Which of the following is correctly matched a Staphylococcus spheres in clumps a Surface associated communities of one or more species of bacteria 24 Bacteria have extra chromosomal pieces of DNA in the cytoplasm called a Plasmids 25 Which of the following is not a function associated with the cytoplasm of bacteria a Plays a role in the division of the cytoplasm into distinct compartments 26 What is the function of magnetosomes a Orients cells along the earth s magnetic field so it is easier to find the preferred oxygen environment proteins 27 Which of the following is not a function normally associated with cytoplasmic membrane a Synthesis of cytoplasmic membrane components 28 A major difference between gram positive and gram negative cell walls is the presence of a Lipopolysachharides in gram negative walls 29 The bacterial cell wall a Provides resistance to osmotic pressure and mechanical forces