Chapter 3 Microbiology

The concept of a prokaryote was first fully outlined in 1962 by

The genus of bacteria that undergoes cell division in random planes, forming grapelike clusters of round bacteria, are the __________.

Bacteria that do not have a fixed shape are said to be __________.

A branched network of hyphae formed by the Actinomycetes is called a __________.

Actinomycetes form long filaments called ___________.

The term used to describe bacteria that are intermediate in shape between spherical and rodshaped is

Bacterial cells that are variable in shape are called

Square planar arrangement of cells that forms when round bacteria remain attached to each other during reproduction are called

Flexible bacteria with a helical shape are called

Rigid bacteria with a helical cell shape are called

The term used to describe bacteria that are shaped like curved rods is

The term used to describe bacteria that are rod shaped is

The term used to describe bacteria that have a spherical shape is

Sterol-like molecules called hopanoids are thought to be important for the structural integrity of many bacteria because of their suspected role in membrane stabilization.

The cytoplasmic membrane of bacteria

The lipopolysaccharide (LPS) that is found in the outer membrane of gram-negative bacteria is also known as

Which of the following is/are true of capsules?

Proteins that are loosely associated with the cytoplasmic membrane are called __________proteins.

Proteins that are embedded within the cytoplasmic membrane and not easily extracted are called __________ proteins.

Shrinkage of the plasma membrane away from the cell wall when the bacterium is placed in a hypertonic environment is called

Lipids with polar and nonpolar ends are said to be

Although penicillin inhibits peptidoglycan synthesis, bacterial cells will continue to grow normally in the presence of penicillin in a(n) __________ environment.

All of the following statements about the periplasmic space are true except: "It is located between the plasma membrane and outer membrane of gram-negative bacteria." "It contains hydrolytic enzymes and binding proteins involved in nutrient acquisition."

Which of the following protects bacteria from lysis in dilute solutions and helps to determine their cellular morphology or shape?

Sortase is a protein enzyme of bacteria that

The cell membrane is a rigid structure that provides bacteria with their characteristic shapes.

Gram-positive bacteria have a thinner layer of peptidoglycan than gram-negative bacteria.

Gram-positive bacteria have a structurally and chemically more complex cell wall than gramnegative bacteria.

Bacteria growing at lower temperatures have more saturated fatty acids in their membranes.

When the cell wall is removed from a Gram-negative bacterium without removing the outer membrane, the resulting form is called a(n) __________.

Enzymes that are secreted out of the cell to aid in the acquisition and digestion of environmental nutrients are called __________.

Molecules or regions of molecules that readily interact with water are said to be __________, whereas molecules or regions of molecules that are insoluble in water or do not readily interact with water are said to be __________.

A __________ layer consists of diffuse unorganized polysaccharide material that lies outside the cell wall and is easily removed.

A __________ is a polysaccharide layer that lies outside the cell wall and is not easily removed.

A(n) __________ layer is a layer of protein or glycoprotein that exhibits a pattern resembling floor tiles.

The most widely accepted current model for membrane structures is called the __________model.

The layers of peptidoglycan of the bacterial cell wall can be cross-linked by peptide intrabridges or by direct cross-linking.

A feature unique to some archaeal plasma membranes is that they may

Cell walls of most Archaea and bacteria contain peptidoglycan.

_______ is a peptidoglycan-like molecule found in the cell walls of some archaea.

The hydrocarbons found in the membranes of archaea are identical to those found in bacteria.

Which of the following is not true of bacterial plasmids?

Some photosynthetic bacteria produce gas vacuoles that regulate their buoyancy but contain no lipid.

Intracellular granules of organic or inorganic material that are stockpiled by bacteria for future use are called __________.

Bacteria have a region of the cytoplasm known as the __________, which is not bounded by a membrane but contains the chromosome.

Small circular DNA molecules capable of replicating and containing genes that are useful but not necessary to the bacterium are called __________.

Some species of aquatic bacteria use inclusion bodies known as ________ to orient themselves in Earth's magnetic field.

Bacterial and archaeal ribosomes are known as _____ ribosomes, based on their sedimentation coefficient.

_______ are the site of protein synthesis in the cell.

Sedimentation coefficients are proportional to the molecular weight of a particle and are not affected by the volume and shape of the particle.

Bacterial flagella are composed of three parts: the ______ body, which is embedded in the cell, the hook, and the _______, which is the longest part of the flagellum.

The type III bacterial protein secretion machinery:

Export of flagellin subunits is mediated by

Proteinacious projections from the surface of a bacterium that are used to mediate conjugation are called sex __________, whereas projections that mediate attachment to surfaces such as host cells are called __________.

During the assembly of the flagellar filament, the flagellin protein monomers assemble at the cell proximal base of the flagellum.

Archaeal flagella are superficially similar to bacterial flagella, although archaeal flagella are much thicker than bacterial flagella.

Matching: Match the definition with the word. 1) monotrichous, 2) peritrichous, 3) lophotrichous, 4) amphitrichous: a) a single flagellum, b) a single flagellum at each pole of an organism, c) a cluster of flagella at one or both ends of an organism, d) a relatively even distribution of flagella over the entire surface of the bacterium

The power used by most flagellar motors is produced by

Chemotaxis is a process by which bacteria

The rotation of bacterial flagella is powered by ATP hydrolysis.

The bacterium E. coli swims in a straight line, called a __________, for a few seconds; then it stops, __________, then swims away in a new direction.

In many spirochetes, multiple flagella combine to form a bundle known as a(n)____________ fibril, which winds around the cell and confers motility on the cell.

Twitching or gliding motility involves

Endospores represent a challenge to the fields of industrial and medical microbiology because

__________ is the process through which endospores are formed within a vegetative cell.

__________ is the main part of the process through which a vegetative cell is formed from an endospore.

The vegetative cell (mother cell) in which an endospore forms

The structural component of bacterial cell walls that is also called peptidoglycan

Plasma membrane and everything contained within

A unit of measure of the sedimentation velocity in a centrifuge

A circular, double-stranded DNA molecule in prokaryotes that can exist and replicate independently of the chromosome

A gap between the plasma membrane and the cell wall of bacteria

Organisms with peptidoglycan-like polymer with L-amino acids instead of D-amino acids

Bursting of cells that occur when cells are placed in hypotonic solution so that water flows in the cell

Well organized polysaccharides outside the cell wall that are not easily washed off

Diffuse, unorganized polysaccharides outside the cell wall that are easily removed

Protein or glycoprotein layer that exhibits a patter not unlike floor tiles

Hairlike appendages that are thinner than flagella and are usually involved in attachment rather than motility

A flexible filament that is used for motility by spirochetes

Movement toward chemical attractants or away from repellents

A structure formed by some species of bacteria that is resistant to some environmental stress

The process of forming endospores within a vegetative cell

A network of polysaccharides extending from the surface of bacteria and other cells

Inclusion bodies that serve as a reserve of enzymes and site of CO2 fixation

Inclusion bodies that store extra nitrogen for bacteria

A polymer of glucose units; it serves as a carbon storage reservoir for many bacteria

A plasmid that can exist independent of the host chromosome or be integrated into it

A plasmid that has genes for pili and can transfer copies of itself to other bacteria

A plasmid that carries genes that encode resistance to antibiotics

A plasmid that carries genes for a toxin, and thus renders the host bacterium pathogenic

A plasmid that carries genes for enzymes that degrade environmental substances such as aromatic compounds and pesticides