Medical Microbiology: Ch. 4 Survey of Prokaryotic Organisms

Indicate each item that would be smaller than a typical E. coli cell.

Staphylococcus aureus cell an Ebola virus

Excess nutrients that the cell may store for later use may be found within

cytoplasmic granules.

The best understood bacterial cytoskeletons are composed primarily of

actin

Which term(s) refer to cells without cell walls?

mycoplasma sphereoplast protoplast

The functions of the cell envelope include

Helping to determine the shape of a bacterial cell Preventing rupture of the cell from increased internal pressure. Allowing the cell to regulate the transport of many molecules from the internal to external environment.

Match the cell component with its role in the cell.

1. Chromosome: The structure which contains the essential DNA of the cell 2. Plasmid: The structure which contains the nonessential DNA of the cell 3. Ribosome: Composed of RNA and protein, this structure synthesizes new proteins. 4. Cytoskeleton: This structure is a network of protein polymers that helps stabilize the shape of the cell from within. 5. Inclusion bodies: This structure stores nutrients during periods of ample resources to compensate for times when nutrients are scarce. 6. Granules: This structure stores inorganic compounds, such as sulfur and polyphosphate.

Please order the following choices to reflect the generalized anatomy of bacterial cells with "1" being the innermost cell component and "4" being the outermost cell component.

1. cytoplasmic matrix 2. cell membrane 3. cell wall 4. glycocalyx

Please match the appendages to the description that most accurately describes their function to distinguish among the types of external cell appendages.

1. flagella - composed of a filament, hook and basal body, these cell appendages provide movement to the cell 2. fimbriae - these short, bristle-like projections are used to attach the cell to other cells or surfaces 3. pili - these long, tubular appendages allow cells to conjugate to other cells 4. axial filaments - these long, coiled threads provide movement to spirochetes

Please match each cell component with the statement that most accurately describes it to test your understanding of glycocalyx, the different forms and their most important functions.

1. glycocalyx - this is the general term which describes all the various coatings covering the surface of the cell 2. slime layer - this loosely attached, thin mucoid layer protects the cell from drying out or losing nutrients 3. capsule - this layer of polysaccharides and/or proteins is tightly bound to the cell and contributes to the cell's pathogenicity

Please match the cell components with the type of cell where it is found. If the component is found in both gram-positive and gram-negative cells, select "both gram-positive and gram-negative cells"

1. teichoic acid: gram-positive cells 2. lipopolysaccharide; outer membrane: gram-negative cells 3. peptidoglycan; cell membrane: both gram-positive and gram-negative cells

The bacterial flagellum moves

by rotation that is powered by the proton motive force.

The two groups of obligate intracellular bacteria are the __________, usually spread by contact, and the __________, usually transmitted by the bites of arthropods.

chlamydias; rickettsias

Other than maintaining the shape of the cell, what is the primary function of the cell wall, and which component contributes most to this function?

maintaining strength; peptidoglycan

Please select all of the characteristics that define life and living things.

the ability to synthesize new cell components or release energy through chemical reactions ability to respond to their environment ability to control the flow of some materials across cell boundaries

The primary function of the cell membrane is

to regulate the transport of molecules in and out of the cell.

Match each phylum with the correct description.

1. Phylum Chlorobi: green sulfur bacteria 2. Phylum Cyanobacteria: photosynthetic bacteria that may be green, yellow, red, or orange in color 3. Phylum Deinococcus: highly resistant to radiation and desiccation 4. Phylum Thermotogae: thermophilic halophiles found in deep sea vents 5. Phylum Aquificae: small thermophilic rods found in underwater volcanoes

Diseases caused by obligate intracellular bacteria include

Rocky Mountain spotted fever. endemic typhus.

The cell envelope is the external covering that lies outside of the cell cytoplasm and is composed of the __________ and __________.

cell membrane cell wall

Please select all of the following which are found in all cells regardless of cell type.

cell membrane cytoplasm DNA

Please select all of the following which are contents of the cell cytoplasm.

chromosome ribosome water

Which of the following attributes is true about bacterial ribosomes?

found in the cytoplasm contains RNA subunits made of 50S and 30S subunits

Which of the following has historically been the first division in a system of bacterial taxonomy?

gram-positive versus gram-negative cells

Bacterial species are defined in a fundamentally different way than mammalian species are. This is because

mammals reproduce sexually while bacteria reproduce asexually.

Choose all of the techniques commonly used to classify bacteria.

morphology bacterial physiology serological analysis genetic analysis

Of the photosynthetic bacteria, cyanobacteria produce __________ as a product of photosynthesis, but the green and purple sulfur bacteria do not produce this substance.

oxygen

The molecule primarily responsible for the strength and stability of the bacterial cell wall is

peptidoglycan

Which of the following is a characteristic of green and sulfur bacteria?

photosynthetic contain pigments contain bacteriochlorophyll

Please select all of the following that are characteristics of archaea.

prokaryotic circular chromosome contain long-chain, branched hydrocarbons in the cell membrane

The __________ level of bacterial organisms refers to a group of organisms that all share the same traits while the subspecies level refers to the variation or differences of individual cells within that group.

species

Match each phylum with the correct description.

1. Phylum Euryarchaeota: produce methane and can withstand high salt environments 2. Phylum Crenarchaeota: depend on sulfur for growth, found in extreme habitats like hot springs or extreme cold 3. Phylum Nanoarchaeota: extremely small archaea found in salt mines

Match each phylum with the correct description.

1. Phylum Firmicutes: mostly gram-positive bacteria with a low G+C content 2. Phylum Proteobacteria: gram-negatives including rickettsias and enterics 3. Phylum Spirochetes: slender, twisted cells that move by means of periplasmic flagella 4. Phylum Chlamydiae: obligate intracellular parasites that are extremely small in size

Please match the technologies with the statements that most accurately describe them to test your understanding of the methods and characteristics used in classifying bacteria.

1. morphology: these tests use cell shape and Gram reaction to classify organisms 2. bacterial physiology/biochemistry: these tests use the presence or absence of biochemical processes and enzymes to group organisms 3. serological analysis: these tests use antibody reactions to identify an organism or to determine relatedness 4. genetic techniques: these tests use DNA to determine the identity of an organism

Please match the terms related to flagella with the statement that most accurately describes them to test your understanding of the attachment patterns of bacterial flagella.

1. polar - this type of flagella can be found at either or both ends of a cell 2. monotrichous - this pattern has one flagellum attached at one end of the cell 3. lophotrichous - this pattern has groups of flagella all originating from the same point on the cell 4. amphitrichous - this pattern has flagella at both poles of the cell 5. peritrichous - this pattern consists of flagella randomly distributed around the cell

Cyanobacteria are of interest (and are named for) their ability to degrade areas contaminated with cyanide.

False Explanation: Cyanobacteria are named for the blue-green pigment, phycocyanin, that provides them with their color and allows them to photosynthesize.