Quiz 3

Question 1

Microbe

Answer 1

Was coined to refer collectively to the microscopic organisms, including bacteria, fungi, protozoan, and viruses. However, term is used commonly to denote any bacteria that are harmful and pathogenic

Question 2

Bacterium/bacteria

Answer 2

The simplest organisms that can only be seen through a microscope

Question 3

Cell envelope

Answer 3

A complex, multilayered structure that serves to protect the organism from the unpredictable and inhospitable external environment. “Skin” of the microorganism

Question 4

Gram staining

Answer 4

A widely used diagnostic laboratory staining method that identifies bacteria based on the fundamental structural characteristics of the bacterial cell envelope

Question 5

Gram positive bacteria (purple stain)

Answer 5

Has a single, thick multilayered, mesh-like cell wall composed of peptidoglycan

Question 6

Gram negative bacteria (red stain)

Answer 6

This type of bacteria has two membranes: the outer membrane faces the external environment. The inner cytoplasmic membrane faces the interior of the cell

Question 7

Planktonic

Answer 7

Microbes that are free floating. Rare

Question 8

Biofilm

Answer 8

A complex and dynamic microbial community containing a diverse array of many types of microbial species. Embedded within a self protective matrix that adheres to a living or non living surface

Question 9

Polymicrobial

Answer 9

Biofilm communities are characterized by the presence of several species of microorganisms

Question 10

Oral biofilm

Answer 10

Is a polymicrobial, three dimensional community of numerous microbial species, embedded in a protective matrix that consists of microbial metabolic products and/or host components, such as salivary glycoproteins

Question 11

Commensal bacteria

Answer 11

The oral cavity is inhabited by indigenous, resident bacteria

Question 12

Symbiosis

Answer 12

Living in harmony (in heath, commensal microbes in the oral biofilm have a symbiotic relationship with the host)

Question 13

Dysbiosis

Answer 13

Microbial imbalance on or inside the body

Question 14

Transmission

Answer 14

The transfer of bacteria from the oral cavity of one person to another

Question 15

Acquired pellicle

Answer 15

A film composed of a variety of salivary glycoproteins (mucins) and antibodies. Purpose is to protect enamel from acidic activity

Question 16

Coaggregation

Answer 16

Process by which genetically distinct bacteria become attached to one another

Question 17

Extracellular protective matrix (extracellular polymeric substance)

Answer 17

Once firmly attached, bacteria begin to secrete this surrounding protective substance

Question 18

Microbial blooms

Answer 18

Periods when specific species or groups of species grow at rapidly accelerated rates

Question 19

Mushroom shaped micro colonies

Answer 19

Microbes cluster to form this, they are attached to the tooth surface at a narrow base

Question 20

Fluid channels

Answer 20

As the plaque biofilm developes, fluid channels are formed that penetrate the extracellular protective matrix. Direct fluids in and around the biofilm bringing nutrients and oxygen to microbes and carrying waste away

Question 21

Quorum sensing

Answer 21

Bacterial communication occurs when microbes within biofilm release and sense small proteins (signaling molecules)

Question 22

Tooth associated plaque biofilms

Answer 22

Bacteria that are attached to the tooth surface

Question 23

Tissue associated plaque biofilms

Answer 23

Bacteria that adhere to the epithelium

Question 24

Unattached bacteria

Answer 24

In addition to the attached bacteria, the periodontal pocket also contains many free floating bacteria that are not part of the biofilm

Question 25

Nonspecific plaque hypothesis

Answer 25

Postulated that the accumulation of bacterial biofilms leads to periodontal disease

Question 26

Specific plaque hypothesis

Answer 26

A later theory, postulated that specific pathogenic bacteria and their products in the biofilm lead to periodontal disease

Question 27

Ecological plaque, microbial homeostasis-host response, keystone pathogen-host response hypothesis

Answer 27

We now recognize that a pathogenic microbial biofilm is a prerequisite for periodontitis to develop, but the presence of a pathogenic oral biofilm alone is insufficient to cause the disease. And while red complex microorganisms are strongly associated with an inflammatory disease, there is no current evidence to support the argument that the red complex bacteria are potent initiators of the disease

Question 28

Keystone species

Answer 28

An ecological term to describe a species that has a disproportionately large effect on its community relative to its abundance