Exam 1 Principle 1-1 (Grace's Version) Flashcards
What microorganisms make up the microbiome of the human body?
bacteria, viruses, fungi, protozoa
What microorganism does not contribute to the human microbiome?
helminths (worms)
What are parasitic organisms?
symbionts that harm or live at the expense of their host
What are commensal organisms?
also known as normal microbiota
-microbes frequently found on or within the bodies or healthy persons
What is an infection?
growth and multiplication of parasite on or within a host
What is an infectious disease?
disease resulting from infection
Do infectious diseases always come from outside the body?
no. they can be caused by exogenous sources, but can also be caused my microorganisms present in the body normally, but moving to a different area of the body or during states of lowered immunity
What is a pathogen?
any parasitic organism that causes infectious disease
What is primary (frank) pathogen?
pathogen that causes disease by direct interaction with host
-will cause disease in host regardless of immune status or presence of other microorganisms
What are opportunistic pathogens?
pathogens that cause disease only under certain circumstances
-oral candidiasis is an example
What is pathogenicity?
ability of parasite to cause disease
What is virulence factor?
any component of a pathogenic microbe that is required for or that potentiates its ability to cause disease
What are the steps in an infectious disease ?
- encounter
- entry
- spread
- Multiplication
- Damage
- Outcome
What are the three types of encounters that can occur?
exogenous
endogenous
congenital
What is an exogenous encounter?
out in the world
-sneeze, cough
What is an endogenous encounter?
a microorganism already present in the body moves to another area and causes issues
ex). organism normally present in the oropharynx is inhaled and colonizes in the lungs. this can cause pneumonia in the lungs
What is a congenital exposure?
exposure of mother to body during pregnancy or birth
What are the two types of entry of infectious disease?
ingress and penetration
What is ingress of an infectious disease?
inhalation or ingestion
What is penetration of infectious disease?
microbes pass through epithelia directly (attachment and internalization), insect bites, cuts and wounds, organ transplants and blood transfusions
What are the ways that infectious disease can spread?
lateral propagation- tissue to tissue
dissemination- travel far distances
What can affect the way that infectious diseases can spread?
anatomical factors (set up of sinuses)
active participation by microbes (if motile, pathogens can move far)
What can affect the multiplication of infectious disease?
environmental factors and subversion of host defenses
What are the possible outcomes of infectious disease?
microbe wins, host wins, or they learn to coexist
What is normal microbiota?
microbes frequently found on or within the bodies of healthy persons
When does colonization of bacteria begin?
rapidly after birth
-thousands of bacterial species are part of normal flora
How much of the human body mass is bacteria?
1-3%
What is the benefit to having normal microbiota?
-produce some vitamins we are unable to make on our own
-break down our food to extract nutrients
-teach immune system to recognize dangerous invaders
-make helpful anti-inflammatory compounds
-occupy space to crowd out disease causing bacteria
-detoxification of carcinogens
What parts of the bodies have the largest amounts of bacteria?
-skin
-respiratory tract
-digestive tract
-urinary tract
-genital system
What are the sterile locations of the body?
blood
cerebrospinal fluid
synovial fluid
deep tissues
What is periodontitis?
overgrowth of particular bacteria in gingival cervices
What is pneumonia?
defenses lowered and microaspirations of pneumococci
What bacteria is seen in catheter associated infections?
staphylococci
What does the oral flora include?
bacteria (archea)
fungi
protozoa
viruses
How many different species of bacteria are seen in the oral cavity?
around 700
What are the oral habitats for oral flora?
-buccal mucosa
-dorsum of tongue
-tooth surfaces
-crevicular epithelium
-dental appliances
What can cause issues for microbial cells?
-nutritional fluxes
-maintaining occupancy
-resistance to damage
What factors modulate the growth of bacteria in the oral cavity?
-anatomical features make it harder to clean
-shape and topography of teeth
-malalignment of teeth
-poor quality of restorations
-saliva
-crevicular fluid
How does saliva modulate the growth of bacteria in the oral cavity?
promote adhesion to the tooth surface
source of food
promote aggregation of bacteria
inhibit growth of microbes by nonspecific defense
maintain pH
What is an absolute requirement for all living organisms?
membranes
What are characteristics of plasma membrane
-contain lipids and proteins
-form bilayer
-proteins can be imbedded in the membrane of on the outside
-highly organized, asymmetric, flexible, and dynamic