Chapter 13- Agents Of Infectious Disease

Question 1

True or False

The main difference between bacteria and viruses is that bacteria contain nucleic acids and viruses do not.

Answer 1

False

Question 2

True or False

A gram positive bacterium has a thin internal cell wall

Answer 2

False

Question 3

What are the three most common bacterial shapes?

Answer 3

1- cocci
2- bacilli
3- spiral

Question 4

What is the difference between a microaerophilic bacterium and an aerobic bacterium?

Answer 4

A microaerophilic bacterium grows best in low oxygen concentration, an aerobic bacterium grows in a normal atmospheric concentration of oxygen

Question 5

Name at least three characteristics that are used to identify bacteria

Answer 5

1- oxygen requirements
2- staining characteristics
3- pH needs

Question 6

Which of the following is not a mode of bacterial locomotion?
A- squirming
B- gliding
C- writhing
D- propulsion

Answer 6

C- writhing

Question 7

A bacteria with cilia will have:
A- hair like structures on the outside of the plasma membrane
B- long, tail-like shape and smooth cell wall
C- a blob-like shape and smooth cell wall
D- a thick capsule surrounding the cell

Answer 7

A- hair like structures on the outside of the plasma membrane

Question 8

Bacteria staining dark blue to purple with gram stain are called:

Answer 8

Gram-positive

Question 9

True or False

Most viruses have a cytoplasm which contains DNA, RNA, and proteins

Answer 9

False

Question 10

What is the definition of virulence?

Answer 10

The degree of pathogenicity of an microorganism

Question 11

Prions are infectious agents that are made up of:

Answer 11

Proteins

Question 12

Many different organisms can grow in a(n)\_\_\_\_\_\_\_ agar, but differences in their reactions can be observed.
A- acidic
B- selective
C- undefined
D- differential

Answer 12

D- differential

Question 13

Which statement is FALSE regarding bacterial capsules?
A- A capsule is a protective envelope
B- Some gram-negative bacteria have a capsule
C- A capsule is produced on the inner side of the cell membrane
D- A capsule can protect against phagocytosis by white blood cells

Answer 13

C- A capsule is produce on the inner side of the cell membrane

Question 14

Mycology is the study of which organism?
A- Fungi
B- Prions
C- Mites
D- Viruses

Answer 14

A- Fungi

Question 15

Which characteristic is true of sucking lice but not true of chewing lice?
A- Sucking lice are host-specific and spread by direct contact
B- Sucking lice do not have wings
C- Sucking lice have legs that can grasp
D- Sucking lice have narrow heads and mouthparts

Answer 15

D- Sucking live have narrow heads and mouthparts

Question 16

Proglottids are rice-like segments of which parasite?
A- Flukes
B- Thorny-head worms
C- Leeches
D- Tapeworms

Answer 16

D- Tapeworms

Question 17

In which group of helminths are tapeworms found?
A- Acanthocephalids
B- Nematodes
C- Trematodes
D- Cestodes

Answer 17

D- Cestodes

Question 18

Which group of worms are generally elongate, cylindrical, and non-segmented?
A- Nematodes
B- Acanthocephalids
C- Cestodes
D- Trematodes

Answer 18

A- Nematodes

Question 19

What is the definition of virulence?
A- The resistance of an organism to the immune system
B- The speed with which an organism can replicate
C- The degree of pathogenicity of an organism
D- The ability of an organism to infect a host

Answer 19

C- The degree of pathogenicity of an organism

Question 20

In comparison with other infectious agents, what is a unique characteristic of prions?
A- Prions cannot grow in the absence of oxygen
B- Prions do not contain nucleic acid
C- Prions only grow where the pH is under 7.0
D- Prions can be destroyed by radiation

Answer 20

B- Prions do not contain nucleic acid

Question 21

Spherical or round bacterium are called:
A- cocci
B- bacilli
C- vibrios
D- spirochetes

Answer 21

A- cocci

Question 22

Mosquitos are vectors for transmission of which of the following parasites?
A- heartworms
B- tapeworms
C- strongyles
D- pinworms

Answer 22

A- heartworms

Question 23

Which decontamination method is the only way to ensure complete destruction of prions?
A- strongly acidic detergents
B- formaldehyde
C- radiation
D- incineration

Answer 23

D- incineration

Question 24

Which of the following arachnids are NOT commonly found in mice fur?
A- Mycoptes musculinis
B- Radfordia affinis
C- Sarcoptes scabiei
D- Myobia musculi

Answer 24

C- Sarcoptes scabiei

Question 25

What are hydatid cysts? A- cysts produced by an accumulation of lucid in the liver B- fluid-filled cyst containing tapeworm larvae C- sac-like structure that is excreted in the feces of animals infected by Trematodes D- pus-containing skin growths resulting from ectoparaiste infestation around the hair shafts

Answer 25

B- fluid-filled cyst containing tapeworm larvae

Question 26

``` Which type of RNA virus is the measles? A- arbovirus B- coronavirus C- orthomyxovirus D- paramyxovirus ```

Answer 26

D- paramyxovirus

Question 27

A mycelium is formed by which of the following? A- the agglutination of slimy bacterial spores B- viruses growing in culture C- individual yeast cells growing in culture D- a mold colony

Answer 27

D- a mold colony

Question 28

What is Ctenocephalides felis? A- the species of Hirudinea that infests rhesus monkeys B- the insect known as a typical mouse louse C- the arachnid species that causes mange on rabbits D- the most common species of fleas found on cats and dogs

Answer 28

D- the most common species of fleas found on cats and dogs

Question 29

``` Which of the following fungi are microspordia that cause lethargy, tremors, and partial paralysis in rabbits? A- Candida albicans B- Encephalitozoon cuniculi C- Batrachochytrum dendrobatidisis D- Pseudoloma nuerophilia ```

Answer 29

B- Enceohalitozoon cuniculi

Question 30

How do hookworms generally enter the body? A- fecal-oral route B- ingestion of the intermediate host C- inhalation of spores D- penetration of the skin or oral mucosa

Answer 30

D- penetration of the skin or oral mucosa

Question 31

Which statement is TRUE regarding viral reproduction? A- Viruses reproduce in the fluids that surround the cells in the host’s tissues B- Agars are good media that allow virus reproduction and growth without the need for the virus to enter a host cell C- Viruses can replicate outside a cell D- Viruses use the host cell’s energy-producing mechanisms to synthesize their own proteins

Answer 31

D- Viruses use the host cell’s energy-producing mechanisms to synthesize their own proteins

Question 32

Which statement is FALSE regarding flagella? A- Flagella aid locomotion by secreting slime B- They are whip-like filaments that aid locomotion C- The presence of flagella is an important morphological characteristic D- Flagella can be single or can be found in tufts of two or more

Answer 32

A- Flagella aid locomotion by secreting slime

Question 33

``` Hyphae are multicellular tubular structures characteristic of which organism? A- yeasts B- mold C- viruses D- prions ```

Answer 33

B- mold

Question 34

Which of the following accurately describes prions? A- Small infectious agents containing only RNA B- Abnormal proteins that destroy the outer covering of viruses C- Misshapen proteins that invade host cells D- Infectious agents that can easily be destroyed by inactivation of their nucleic acid

Answer 34

C- Misshapen proteins that invade host cells

Question 35

``` Which type of RNA virus is the West Nile virus? A- Orthomyxovirus B- Paramyxovirus C- Arbovirus D- Coronavirus ```

Answer 35

C- Arbovirus

Question 36

``` Cats are the definitive host of which species of apicomplexan parasite? A- Toxoplasma gondii B- Encephalitozoon cuniculi C- Dipylidium caninum D- Balantidium coli ```

Answer 36

A- Toxoplasma gondii

Question 37

``` Which parasites are known as tongue worms? A- leeches B- pentastomids C- thorny-headed worms D- ascarids ```

Answer 37

B- pentastomids

Question 38

``` Bacteria that can grow in the absence of oxygen are known but what term? A- aerobic B- anaerobic C- normal D- microaerophilic ```

Answer 38

B- anaerobic

Question 39

``` Which type of of RNA is carried fro animal to animal by mosquitos, ticks, and lice? A- Paramyxovirus B- orthomyxovirus C- coronavirus D- arbovirus ```

Answer 39

D- Arbovirus

Question 40

``` Dut to the addition of specific nutrients, only a particular organism or type of organism may grow in a ____________ agar. A- selective B- gram-positive C- differential D- gelatinous ```

Answer 40

A- selective

Question 41

Which statement applies to all bacteria? A- They do not require oxygen to survive B- They have a well-defined nucleus C- They can only live inside a host’s cells D- They do not have mitochondria in their cytoplasm

Answer 41

D- They do not have mitochondria in their cytoplasm

Question 42

Which statement is FALSE regarding the effects of prions in the nervous system? A- The extracellular amyloid plaques of prion diseases disrupt neural structure B- Prion activity arises from the formation of extracellular amyloid plaques C- Extracellular amyloid plaques cause the brain to become dry and rigid D- Mad cow disease is a prion disease

Answer 42

C- Extracellular amyloid plaques cause the brain to become dry and rigid

Question 43

``` Which of the following is a common fungal infection in zebra fish? A- Pseudoloma neurophilia B- Clostridium diffile C- Toxoplasma gondii D- Batrachochytrium dendrobatidisis ```

Answer 43

A- Pseudoloma neurophilia

Question 44

``` Bacteria staining pink with Gram stain are called ______. A- Gram-negative B- Gram-positive C- Gram-aerobic D- Gram-neutral ```

Answer 44

A- Gram-negative