Minot Ch4 MicroBiology
Which one of the folliwng statements about rickettsias is false? a. Diseases caused by rickettsias are arthropod-borne. b. Rickets is caused by rickettsia species c. Rickettsia species cause typhus and tuphuslike diseases d. Rickettsias have leaky membranes.
B. Rickets is caused by a Rickettsia species.
Which one of the following statements about Chlamydia is false? a. They are obligate intracellular pathogens. b. They are considered to be entergy parasites c. The diseases they cause are all arthropod-borne d. The are considered Gram-Negative Bacteria.
C The diseases they cause are all antropod-borne
The group of bacteria that lack rigid cell walls and take on irregular shape is
C. mycoplasmas
Which of the flollowing statements about cyanbacteria is false? a. Although cyanbacteria are photosynthetic, they do not produce oxygen as a result of photosynthesis b. At one time, cyanbacteria were called blue-green algae. c. Some cyanbacteria are capable of nitrogen fixation d. Some cyanbacteria are important medically because they produce toxins.
A. Although cyanbacteria are photosynthetic, they do not produce oxygen as a result of photosynthesis
most procaryotic cells reporduce by
A. Binary fission
At the end of the Gram staining procedure, Gram-positive bacteria will be
A. Blue to purple
Which of the following diseases or groups of diseases is not caused by prions? a. certain plant diseases b. chronic wasting disease of deer and elk c. Creutzfeldt-Jacob disease of humans d. "mad-cow" disease
A. Certain plant diseases
An organism that does not require oxygen, grows better in the absence of oxygen, but can survive in atmospheres containing some molecular oxygen is know as a
A. aerotolerant anarobe.
Which of the following statements about archaea is false? a. Archaea are more closely related to eucaryotes than they are to bacteria. b. Both archaea and bacteria are procaryotic organisms c. Some archaea live in extremely hot enviroments d. The cell walls of archaea contain a thicker layer of peptidoglycan than the cell walls of bacteria.
D. The cell walls of archaea contain a thicker layer of peptidoglycan than the cell walls of bacteria.
Which one of the following steps occurs during the multiplication of animal viruses, but not during the miltiplication of bacteriophages?
D. Uncoating
The cell walls of archaea contain a thicker layer of peptidoglycan than bacterial cell walls
False (archaean cell walls do not contain peptidoglycan)
Prions are infectious RNA molecules.
False (prions are infectious proteins; viroids are infectious RNA molecules)
On entering a bacterial cell, all bacteriophages immediately initiate the lytic cycle
False (temperate bacteriophages cause lysogeny)
Most viruses contain both DNA and RNA
False (they contain either DNA or RNA)
Viruses are the smallest infectious agents.
False (viroids and prions are infectious agents that are smaller than viruses)
Mycoplasmas cannot grow on artificial media.
False (yes they can)
All diseases caused by Rickettsia spp. are arthropodborne
True
HIV is an enveloped, double-stranded RNA virus.
True
Organisms in the genus Vibrio are curved bacilli.
True
Rickettsia spp. and Chlamydia spp. cannot be grown on artificial media.
True
_______________ are obligate intracellular pathogens that cause diseases such as trachoma, inclusion conjunctivitis, and urethritis
chlamydias
_______________ are photosynthetic
cyanobacteria
Rod-shaped bacteria arranged in pairs are called
diplobacilli
Spherical bacteria arranged in pairs are called
diplococci
_______________ have no cell walls
mycoplasmas
_______________ are obligate intracellular pathogens that cause diseases such as typhus and Rocky Mountain spotted fever.
rickettsias
The bacteria that cause syphilis and Lyme disease are
spirochetes
Spherical bacteria arranged in clusters are called
staphylococci
Rod-shaped bacteria arranged in chains are called
streptobacilli
Spherical bacteria arranged in chains are called
streptococci