Flashcards in Exam 1 Part 5 Deck (54):
1
What are the 3 eukaryotic microbes of clinical interest?
protozoa, fungi, and parasitic helminths
2
T/F: Eukaryotes can reproduce either sexually or asexually. Some even do both.
True
3
T/F: Protozoa typically lack a cell wall.
True
4
T/F: Most protozoa are pathogens
False; very few are
5
What kind of environment is required by protozoa?
moist environments
6
How do most protozoa reproduce?
asexually
7
T/F: all protozoa produce trophozoites.
true
8
T/F: all protozoa produce cysts
false; some do, but not all
9
What do protozoa have that protect them from osmotic lysis?
contractile vacuoles
10
T/F: 30% of fungi cause diseases of plants, animals and humans (mycoses)
True
11
What is the name given to the nonreproductive body of fungi?
thallus
12
What long, branched, tubular filaments compose the thalli of molds?
hyphae
13
What is the term applied to fungi that produce two types of thalli?
dimorphic
14
What form of dimorphic fungi generally cause diseases?
yeast form
15
What is the term for a tangled mass of hyphae (typically subterranean)?
mycelium
16
T/F: all fungi have the ability to reproduce asexually.
True
17
T/F: all fungi have the ability to reproduce sexually.
false, but most do.
18
What is a pseudohypha?
a series of buds that remain attached to one another and to parent cell
19
AIDS, common colds, hemorrhagic fevers, SARS, and smallpox are all caused by what type of pathogen?
viruses
20
T/F: viruses can have either DNA or RNA.
True
21
What is the name for the protein coat surrounding the nucleic acid core of viruses?
capsid
22
What outer structure do viruses have that encloses the nucelocapsids?
envelope
23
Other than protection, what other function is provided by capsids and envelopes of viruses?
means of attachment to host's cells
24
When is the capsid of a virus removed?
once the virus is inside the host
25
Once inside a host, how does a virus exist?
simply as nucleic acid
26
T/F: viruses are always specific and infect only a particular kind of cell in a particular host.
False; some are generalists and infect many kinds of cells in many hosts
27
What types of organisms are susceptible to viral attack?
ALL types
28
What viral shape consists of capsids of many shapes?
complex
29
What viral shape is spiral in nature?
helical
30
What viral shape consists of a geodesic dome?
polyhedral
31
What is a naked virion?
a virion without an envelope
32
Where is the viral envelope acquired?
from host cell during replication
33
What are the 3 main functions of the viral envelope?
protection, host recognition, and helping viruses enter host cells
34
T/F: virus replication does not usually result in death of the host cell.
False
35
T/F: viral replication is dependent on the hosts' organelles and enzymes to produce new virions.
True
36
What is lysogeny?
a modified viral replication cycle
37
What are prophages?
inactive phages
38
What is it called when phages carry genes that alter phenotype of a bacterium? This can turn harmless bacterium to pathogen.
lysogenic conversion
39
Do animal cells have a cell wall?
no
40
T/F: replication of animal viruses is the same basic replication pathway of bacteriophages.
true
41
Do animal viruses have tails or tail fibers?
no
42
What are the 3 mechanisms of Entry of Animal Viruses?
Direct penetration, membrane fusion and endocytosis
43
What are viruses called when they remain dormant in host cells?
latent viruses or proviruses
44
What parasitic particles are extremely small, circular pieces of RNA and lack capsids?
Viroids
45
What type of organisms are infected by viroids?
plants
46
What are viroidlike agents?
infectious, pathogenic RNA particles that lack capsids
47
What organisms are infected by viroidlike agents?
fungi, NOT plants
48
T/F: Prions lack nucleic acid
True
49
What are the only two ways to destroy Prions?
incineration and autoclaving in sodium hydroxide
50
Where is prion expression most predominant?
nervous system
51
What is the characteristic appearance of prion diseases?
spongy appearance (large vacuoles in the brain)
52
BSE, vCJD, and Kuru are all what kind of diseases?
Spongiform encephalopathies (prion diseases)
53
T/F: prions may lie behind neuronal degenerative diseases like Alzheimer's disease, Parkinson's and ALS.
True
54