Microbio Ch 35: Infection & Pathogenicity

The condition in the host that results from pathogenic parasitic organism growing and multiplying within or on the host is called A. An infection. B. An infectious disease. C. Pathogenesis D. All of these

The final outcome of most host-parasite relationships depends on A. the number of organisms present in or on the host. B. The virulence of the organism. C. The host's defenses. D. all of the choices

Which of the following has no effect on the outcome of the host-parasite relationship? A. The number of parasites on or in the host B. The virulence of the parasite C. The defenses of the host D. All of these have an effect on the outcome of the host-parasite relationship.

Any organism that can cause disease in the host after direct interaction is a A. Focal pathogen. B. Opportunistic pathogen. C. Primary pathogen. D. secondary pathogen.

An __________ pathogen can cause disease in a host with impaired resistance.

Organisms present in tissue for long periods of time

a neutralizing antibody

Requires weakened immune system

not general infection

If a symbiont either harms or lives at the expense of another organism, the relationship is called A. Symbiosis B. Parasitism C. Commensalisms D. Pathogenicity

An organism other than a human that is infected with a parasitic organism that can also infect humans is called a(n) ________ host. A. Reservoir B. Endoparasite C. Transfer D. Intermediate

Which of the following is required of a pathogen to possess in order for it to be successful at causing infectious disease? A. Initially be transported to the host B. Be able to exit the host C. Ability to adhere to, colonize, or invade the host D. Ability to damage the host E. All of the choices

An inanimate object that may be contaminated with a pathogen is called a A. Vector B. Fomite C. Zoonoses D. None of the choices

Which of the following is a facultative intracellular pathogen? A. Viruses B. Brucella abortus C. Rickettsia D. All of the choices

Transfer of pathogens from host to environment and then to another host are said to be transmitted _________.

A ________________ infection is a disease caused by a parasitic organism that is normally found in animals other than humans.

The presence of viruses in the blood is called _______________.

A __________ is an organism that transfers pathogens from one host to another.

site where the pathogen normally resides

inanimate object that may be involved in transmission

does not harm a healthy host

develops during a hospital stay

Vector-borne transmission can be either external or internal. In external (mechanical) transmission, the pathogen is carried A. On a fomite. B. On the body surface of a vector. C. Within the vector. D. All of the choices

Inanimate materials involved in pathogen transmission are called reservoirs. A. True B. False

Pathogens can penetrate to deeper tissues by producing specific virulence structures or enzymes. These products include all of the following except A. Collagenase B. Ribosomes C. Hyaluronidase D. Leukocidins

Bacteria within biofilms exchange A. Plasmids B. Quorum-sensing molecules C. Nutrients D. All of the choices

Many types of bacteria are only _________ when dispersing from more stable and heterogeneous communities known as biofilms.

Virulence may be measured experimentally at the host level by the __________ __________ __________, which measures the number of pathogens that kills 50% of an experimental group of hosts within a specified amount of time. (3 words)

The term __________ refers to the degree or intensity of pathogenicity.

Because LPS is bound to the surface of bacteria, it is called a(n) __________.

A neutralizing antibody against a toxin is called a(n) __________.

Exotoxins can be denatured by iodine to form __________ which are useful in vaccines.

The capacity of an organism to produce a toxin is called __________.

Cholera toxin is an AB toxin. A. True B. False

Many bacteria are pathogenic because they carry large segments of DNA called __________ _________, which were acquired by horizontal gene transfer, and which carry genes responsible for virulence. (2 words)

Once a pathogen has infected the host, __________________ is a measure of the pathogen's ability to spread to adjacent or other tissues.

Gas gangrene caused by Clostridium perfringens results from disruption of cell membranes caused by production of ____________. (2 words, 1 word)

While exotoxin production is most generally associated with gram-positive bacteria, some Gram-negative bacteria also produce exotoxins. A. True B. False

Macrophages are phagocytic cells. A. True B. False

Fever response can be triggered by an endogenous pyrogen called interleukin-1. A. True B. False

Colonization specifically refers to the multiplication of a pathogen on or within a host, and includes the resulting tissue invasion and damage. A. True B. False

Generally, exotoxins tend to be more heat stable than endotoxins. A. True B. False

The only organisms to produce endotoxins are gram-negative bacteria. A. True B. False

Listeria monocytogenes propels itself through mammalian host cells using: A. A modified form of gliding motility. B. Host cell actin and other cytoskeletal proteins. C. Periplasmic flagella. D. Fimbriae based twitching motility.

The toxic component of lipopolysaccharide is called A. Lipid A. B. Exotoxin C. Hemolysin D. O antigen polysaccharide.

In the case of the AB toxins, the function of the B subunit is to A. Act as a neurotoxin. B. Have enzyme activity that causes toxicity. C. act as a superantigen that stimulates T cells to release cytokines. D. bind to host cell receptor.

The characteristics of a pathogen that determine its virulence include which of the following? A. Pathogenicity B. Invasiveness C. Infectivity D. All of the choices

Pathogenicity islands are typically associated with A. Genes encoding tRNA. B. Genes encoding rRNA. C. G+C content similar to the rest of the bacterial genome. D. None of the choices

Which of the following is not a biological effect associated with endotoxin? A. Coagulation B. Paralysis C. Fever D. Fibrinolysis

Endotoxin is released when A. gram negative pathogens lyse or divide. B. Cells are starved for iron. C. cells are lysogenic for the beta phage. D. All of the choices

Which of the following is not a characteristic of lipid A? A. heat stable B. toxic in nanogram amounts C. Weakly immunogenic D. Neurotoxic

Endotoxins include which of the following? A. Diphtheria toxin B. Lipopolysaccharide C. Tetanus toxin D. Botulinum toxin

Which of the following lyse erythrocytes to make iron available to pathogens? A. Hyaluronidase B. Collagenase C. Hemolysins D. Coagulase

Adherence factors (adhesins) that play a role in infectious diseases caused by gram negative bacteria include all of the following except A. Glycocalyx B. Fimbriae C. Lipoteichoic acid. D. Slime layer.

An infectious disease process caused by bacterial or fungal toxins in the blood is called A. Lipoteichoic acid. B. Systemic C. Toxemia D. Phytogenic

By convention, when the word parasite is used without qualification, it often refers to A. A protozoan or helminthic organism. B. Yeast or fungi. C. Bacteria or Archaea. D. Lichens