Characteristics of viruses - Answers -Consist of nucleic acid
-Have a protein shell (capsid)
-Attach and inject nucleic acid
-enter a cell and divert
Characteristics of bacteria - Answers -Prokaryotes
-Single-celled
-no separate nucleus
-contain both DNA and RNA
-binary fission
Characteristics of mycoplasma - Answers -No rigid cell wall
-more delicate
-grow on non-living media
Characteristics of Eukaryotes - Answers -Uni or multicellular
-Genetic material organized in nucleus
Characteristics of Bacterial flora - Answers -Can be considered resident or transient
- Transient flora is found in a specific location often as a result of displacement of resident flora,
injury or trauma
5 reasons why normal flora is clinically important - Answers 1) Healthy active normal flora will
help protect a person from infection by invasive organism
2)It participates in metabolism of host (synthesize vitamin K)
3)Disturbances in the ecology and balance of the normal flora may be produced by antibiotic
therapy
4)Controlled by various host defences and deficiencies
5) Its presence in cultures may confuse the interpretation of laboratory results
When do bacterial infections occur? - Answers When a single species becomes predominate at
a site at which there is normally many species
, or
When a single organism invades a body site that is normally sterile
What are mechanical barriers - Answers -The skin and mucous membranes lining the
passageways of the respiratory, digestive, urinary, and reproductive systems that prevent the
entrance of some infectious agent
What is adherence? - Answers -The first requirement for bacterial invasion
-Adhesion of bacteria to the host tissue is a prerequisite for the initiation of an infectious
process
What is phagocytosis? - Answers -Capable of ingesting bacteria and killing them
-Crucial for defence against invasion by bacteria
What are antibodies? - Answers Specialized proteins that aid in destroying infectious agents
What is compliment? - Answers -A set of circulating protein in the blood
-Will make pathogen more attractive for white blood cells
What is MAC? - Answers -Membrane attack complex
-Create a pore to make the contents (bacteria) leak out and die
-happen with the absence of antibody.
What is cell mediated immunity - Answers type of immunity produced by T cells that attack
infected or abnormal body cells
What is exotoxin production? - Answers -Proteins that are synthesized by bacteria then released
-Exert their effects at an anatomical location remote from the bacteria that originally
synthesized them
The host defence against exotoxins is... - Answers Antibody
If a host is missing phagocytic cells they are at risk for - Answers -Staphylococcus aureus
-Streptococcus pneumoniae
If a host is missing antibody mediated immunity they are at risk for - Answers -Streptococcus
pneumonia
-Viral infections
If a host is missing cell mediated immunity they are at risk for - Answers -Tuberculosis