Deck 24: Actinobacteria: the High G 1 C Gram-Positive Bacteria

Question 1

Members of the genus Micrococcus are frequently pigmented and may grow in yellow,red,or orange colonies.

Answer 1

True

Question 2

The genus Arthrobacter has a distinctive growth cycle in which branched rod-shaped bacteria are produced in the exponential phase,and cocci are found in stationary phase cultures.

Answer 2

True

Question 3

Septa divide the actinomycete mycelia into cells,each containing a single nucleus.

Answer 3

False

Question 4

Actinomycete spores are usually formed on __________ mycelia.

Question 5

The sexual spores of actinomycetes are called sporangiospores.
ASM

Question 6

Members of the genus Actinomyces are either facultative or strict anaerobes that require ________ for optimal growth.

Question 7

Members of the genus Actinomyces are either straight or slightly curved rods,or slender filaments with true branching.

Question 8

Although actinomycetes vary in many ways,they all share a common type of cell wall.

Question 9

Actinomycetes produce many of the antibiotics we use in medicine.

Question 10

Although the spores of actinomycetes are not as heat resistant as endospores,the extent of heat resistance they demonstrate can be used to help classify these organisms.

Question 11

A distinguishing characteristic of actinomycetes that can be used to classify these organisms is the types of sugars found in extracts of the organisms.

Question 12

Actinomycetes degrade a variety of organic compounds and are,therefore,important in mineralization processes in the environment.

Question 13

Some of the high G + C gram-positive bacteria such as Arthrobacter divide by means of snapping division.

Question 14

Actinomycetes are gram-positive,spore-forming bacteria.
ASM

Question 15

A(n)_____________ mycelium is a branching network of fibers on and/or beneath the surface of the agar growth medium.

Question 16

Features considered taxonomically important to the actinomycetes include peptidoglycan composition and structure,and morphology and color of mycelia and sporangia.

Question 17

The actinomycetes are capable of degrading a wide variety of organic compounds.

Question 18

A(n)_____________ mycelium is a branching network of filaments that rises above the agar growth medium.

Question 19

Septa divide the actinomycete mycelia into long cells each containing several nucleoids.

Question 20

Although the actinomycetes are generally nonmotile,the spores may be flagellated and,therefore,motile.

Question 21

Of the nearly 150 species in the genus Streptomyces,only S.somaliensis is known to be pathogenic in humans.

Question 22

Which of the following is(are)true about actinomycete spores?

A)They are heat resistant.
B)They withstand desiccation well.
C)They are true bacterial endospores.
D)They are all motile due to the presence of a flagellum.

Question 23

Members of the genus Mycobacterium are said to be ___________ because basic fuchsin dye cannot be removed even with acid-alcohol treatment.

Question 24

The medically useful compounds some actinomycetes produce when forming aerial mycelia are called

A)anti-metabolites.
B)primary metabolites.
C)secondary metabolites.
D)inhibitory metabolites.

Question 25

Bifidobacterium bifidum is a major pathogen in breast-fed babies.

Question 26

Nocardia cause biodeterioration of rubber joints in water and sewer pipes.

Question 27

The streptomycetes form spores on their substrate mycelia.
ASM

Question 28

Which of the following can be used to help classify actinomycetes?

A)Cell wall composition.
B)Percent G + C content.
C)Phospholipid composition of the membrane.
D)All of these can be used to classify actinomycetes.

Question 29

None of the nocardioform actinomycetes are pathogenic to humans.

Question 30

The maduromycetes differ from other high G + C gram-positives in that they contain the sugar madurose in cell extracts.

Question 31

Actinomycete spores formed within a special structure are called

A)endospores.
B)conidiospores.
C)sporangiospores.
D)myxospores.

Question 32

Actinoplanetes that dwell in the soil play an important role in plant and animal decomposition.

Question 33

Actinoplanetes have extensive __________ mycelia.

Question 34

The special structure in which some actinomycetes form their spores is called a

A)sporangium.
B)conidium.
C)sporatorium.
D)basidium.

Question 35

Most actinoplanetes are found in marine habitats.
ASM

Question 36

Actinomycetes form

A)substrate mycelia and aerial mycelia.
B)heat resistant endospores.
C)prostheca with holdfasts.
D)a sheath made of polysaccharides and proteins.

Question 37

Actinomycetes

A)form asexual spores.
B)form sexual spores,that is,they are used for sexual reproduction.
C)form heat resistant spores.
D)do not form spores.

Question 38

Which of the following is true of the actinomycetes?

A)They divide by budding.
B)They closely resemble the fungi in morphology.
C)Some are photosynthetic.
D)They are unique among prokaryotes in producing sexual spores.

Question 39

Actinomycetes are usually found in __________ habitats.

A)soil
B)freshwater
C)marine
D)all of the choices

Question 40

A few species of actinomycetes have been found to be pathogenic in humans,other animals,and plants.

Question 41

Which of the following is correct about members of the genus Propionibacterium?

A)They are used in the production of Swiss cheese.
B)They cause acne vulgaris and contribute to the development of body odor.
C)They are typically found growing on the skin and in the digestive tract of animals.
D)all of the choices

Question 42

Members of the genus Thermomonospora.

A)Produce single spores on their mycelia.
B)Spores can form on either aerial or substrate mycelia.
C)Can be isolated in compost piles and hay.
D)All of the choices

Question 43

The spores of streptomycetes are

A)motile by means of flagella.
B)motile by means of cilia.
C)motile by means of pseudopodia.
D)nonmotile.

Question 44

Species of the genus Corynebacterium

A)form helical-shaped cells.
B)sometimes divide to form characteristic club-shaped cells and may contain metachromatic granules.
C)are harmless saprophytes.
D)form helical-shaped cells and are harmless saprophytes.

Question 45

The streptomycetes form spores by division of the cells of the aerial mycelia in

A)a single division plane.
B)two division planes simultaneously.
C)two division planes consecutively.
D)multiple division planes.

Question 46

The genus Frankia

A)grows in symbiotic association with the roots of some higher plants and fixes nitrogen.
B)produces heat resistant endospores.
C)is strictly a marine bacterium.
D)produces heat resistant endospores and is strictly a marine bacterium.

Question 47

Members of the genus Mycobacterium cause which of the following diseases in humans?

A)tuberculosis and leprosy
B)abscesses
C)diphtheria
D)meningitis

Question 48

The skin infection streptothrichosis is caused by members of the genus

A)Streptomyces.
B)Dermatophilus.
C)Streptococcus.
D)Propionibacterium.

Question 49

Nocardia are typically found in which of the following environments?

A)soil.
B)intestinal tract of warm-blooded animals.
C)geothermally heated springs.
D)root nodules of some higher plants.

Question 50

Members of the genus Micrococcus are usually

A)aerobic.
B)anaerobic.
C)facultatively anaerobic.
D)microaerophilic.

Question 51

Diphtheria is caused by a member of which of the following genera?

A)Mycobacterium
B)Corynebacterium
C)Propionibacterium
D)Nocardia

Question 52

Members of the genus Micrococcus usually exist as

A)pairs.
B)tetrads.
C)irregular clusters.
D)all of the choices

Question 53

Which of the following antibiotics is (are)produced by actinoplanetes?

A)nalidixic acid
B)gentamicin
C)cycloserine
D)penicillin

Question 54

The actinoplanetes can be found in _______ habitats.

A)soil
B)freshwater
C)marine
D)all of the choices

Question 55

Species of the genus Gardnerella

A)are thought to be a major cause of bacterial vaginitis.
B)are motile spore-forming cocci.
C)are normal flora found on the skin of humans.
D)all of the choices

Question 56

The genus Mycobacterium

A)are strict anaerobes and catalase positive.
B)have cell walls similar to gram negative bacteria.
C)stain acid-fast.
D)are strict anaerobes and catalase positive and have cell walls similar to gram negative bacteria.

Question 57

The genus Arthrobacter

A)is a significant component of the microbial flora of soil.
B)plays an important role in the degradation of some herbicides and pesticides.
C)forms heat resistant endospores.
D)is a significant component of the microbial flora of soil and plays an important role in the degradation of some herbicides and pesticides.