Cytoplasmic Membrane Microbiology Quiz Questions

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 ___________.  

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.  

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

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

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

_______ are the site of protein synthesis in the cell.  

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. (answer, answer)

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.  

__________ 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.  

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

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 __________. (answer, answer)  

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

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

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

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. (answer, answer)  

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

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 __________.  (answer, answer)

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

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

• Coccus

• Bacillus

• Vibrio

• Coccobacillus

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.  

• True

• False

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

• True

• False

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

• Peripheral

• Integral

• External

• Internal

The term used to describe bacteria that are rod shaped is  

• Coccus

• Bacillus

• Vibrio

• Coccobacillus

Proteins that are loosely associated with the cytoplasmic membrane are called __________ proteins.  

• Peripheral

• Integral

• External

• Internal

Bacterial cells that are variable in shape are called  

• Vibrio

• Pleomophic

• Coccobacilli

• Hyphal

Chemotaxis is a process by which bacteria 

• Move toward an attractant or away from a repellent.

• Avoid phagocytosis.

• Respond metabolically to the presence of autoinducer molecules.

• Move on solid surfaces by means of type IV fimbriae.

Which of the following is/are true of capsules?  

• They help bacteria escape phagocytosis by host cells.

• They retain water and help prevent desiccation of the bacteria.

• They prevent entry of many bacterial viruses.

• All of the choices

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

• True

• False

The cytoplasmic membrane of bacteria  

• Retains the cytoplasm and its contents.

• Acts as a selectively permeable barrier, allowing some molecules to pass while preventing the movement of others.

• Is the major site of ATP synthesis in aerobes.

• All of the choices

Rigid bacteria with a helical cell shape are called  

• Vibrios

• Spirilla

• Spirochetes

• Coccobacilli

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

• 50S

• 30S

• 80S

• 70S

Lipids with polar and nonpolar ends are said to be  

• Amphipathic

• Amphibolic

• Bilateral

• None of the choices

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

• Streptococci

• Staphylococci

• Tetrads

• Sarcinae

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

• Hypotonic

• Isotonic

• Hypertonic

• Nonpolar

The rotation of bacterial flagella is powered by ATP hydrolysis. 

• True

• False

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

• Coccus

• Bacillus

• Vibrio

• Coccobacillus

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

• They are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive.

• Endospore-forming organisms are often dangerous pathogens.

• Endospores are significantly smaller than vegetative cells.

• Endospores are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive, and endospore-forming organisms are often dangerous pathogens

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

• True

• False

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

• True

• False

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

• Cocci

• Bacilli

• Vibrio

• Coccobacilli

Flexible bacteria with a helical shape are called  

• Vibrios

• Spirilla

• Spirochetes

• Coccobacilli

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

• True

• False

Cell walls of most Archaea and bacteria contain peptidoglycan.  

• True

• False