Ch4 Prokaryotic Cells & microorganisms

Which of the following attributes is true about bacterial ribosomes?

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

A taxonomical outline of bacterial species based on shared evolutionary histories would be described as a

phylogenetic system.

The cell membrane is composed of __________.

proteins dispersed throughout a phospholipid bilayer

Ribosomes function primarily to

synthesize proteins.

The primary function of the cell membrane is

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

Please select all of the statements that are true about endospores.

Bacterial endospores are highly resistant to heat, drying, and radiation. Endospores resist boiling and therefore steam must be used to destroy endospores present in food. Endospores can exist in the environment for indefinite periods of time.

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.

Diseases caused by obligate intracellular bacteria include

Rocky Mountain spotted fever. endemic typhus.

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

Staphylococcus aureus cell an Ebola virus

The best understood bacterial cytoskeletons are composed primarily of

actin

From the following list, choose all of the functions that can be performed by pili or fimbriae.

attachment to eukaryotic cells biofilm formation mating twitching motility

The bacterial flagellum moves

by rotation that is powered by the proton motive force.

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

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

chlamydias; rickettsias

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

chromosome ribosome water

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

cytoplasmic granules.

Classification systems are used to organize bacterial pathogens by the type of disease or infection each causes.

false

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

false

Which of the following correctly describe the color of different cells after using the Gram staining technique?

gram-negative—pink/red gram-positive—purple

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

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

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

mycoPLASMA sphereoplast protoplast bacillus

Unlike eukaryotes, bacterial DNA is not enclosed by a nuclear membrane. Instead, bacterial DNA is condensed into a region called the __________. Some bacteria also carry additional DNA elements called __________, which in some cases encode genes for antibiotic resistance.

nucleoid plasmid

Choose the answer that best completes this statement's blanks in the correct order. When all the flagella on a cell rotate in a counterclockwise fashion, the cell is propelled forward in a movement known as a __________, but when the flagella reverse direction, the cell stops and changes course in an action known as a __________.

run; tumble

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

Bacteria called __________ display a serpentine mode of movement as a consequence of their periplasmic flagella called __________.

spirochetes axial filaments

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