Classes of Micro-organisms
This class of microorganism is composed of prokaryotic cells and reproduces by binary fission.
What are bacteria.
This gram-positive coccal bacterium, shown in Figure 8.2, commonly causes skin infections such as boils and cellulitis
What is Staphylococcus aureus?
This family of viruses causes “the flu” and is characterized by surface antigens hemagglutinin (H) and neuraminidase (N).
What is influenza virus?
This opportunistic yeast, listed in Table 8.6, commonly causes oral thrush and vaginal infections.
Candida Albicans
This type of immunization involves administration of a vaccine to stimulate the host to produce their own antibodies and memory cells.
What is active immunization?
These infectious agents are acellular and must use a host cell’s machinery to replicate
What are viruses?
These bacterial products, such as botulinum toxin, are secreted proteins that can cause severe tissue damage even in low concentrations.
What are exotoxins?
This virus causes acquired immunodeficiency syndrome (AIDS) by infecting CD4+ T lymphocytes.
HIV
Figure 8.5 demonstrates that fungi can exist in these two main morphologic forms: unicellular and filamentous.
What are yeasts and molds?
This type of therapy provides immediate, short-term protection by giving preformed antibodies, such as immune globulin.
What is passive immunotherapy?
These eukaryotic organisms include yeasts and molds and can cause opportunistic infections.
What are fungi?
This type of toxin is part of the outer membrane of gram-negative bacteria and is released when bacteria die or are lysed.
What is endotoxin (lipopolysaccharide, LPS)?
Figure 8.4 depicts this process of major genetic change in influenza viruses, often leading to pandemics.
What is antigenic shift?
This dimorphic fungus, found in soil with bird or bat droppings, can cause lung infection when spores are inhaled.
What is Histoplasma capsulatum?
Table 8.8 shows that widespread use of these biomedical tools has dramatically reduced the incidence of diseases like measles and polio in Canada.
What are vaccines?
This class of infectious organism includes protozoa and helminths such as tapeworms and roundworms.
What are parasites?
One immune-evasion strategy in Table 8.3 is when bacteria form this protective community on surfaces, which makes them harder for antibiotics and immune cells to penetrate.
What is a biofilm?
Minor point mutations in influenza virus surface antigens that cause seasonal outbreaks are called this.
What is antigenic drift?
This protozoan parasite, from Table 8.7, is transmitted by Anopheles mosquitoes and causes cyclical fevers and hemolysis.
What is Plasmodium (malaria)?
Vaccines against encapsulated bacteria like Streptococcus pneumoniae work partly by inducing antibodies to this outer structure.
What is the polysaccharide capsule?
Surface barriers that can protect us from pathogens
Normal Flora
This common cause of pneumonia and meningitis in adults is a gram-positive diplococcus often colonizing the nasopharynx.
What is Streptococcus pneumoniae?
This DNA virus causes varicella (chickenpox) and herpes zoster (shingles).
What is varicella-zoster virus (VZV)?
This intestinal protozoan parasite causes prolonged, watery diarrhea and can be contracted from contaminated water, especially in daycare settings.
What is Giardia lamblia (Giardia intestinalis)?
This concept describes the indirect protection of unvaccinated individuals when a high percentage of the population is immunized.
Herd Immunity