Infectious Disease Flashcards
Study, study, study!
What is disease?
A disease is any cause that impairs the function of an individual in some way; that is, it harms the individual.
Difference between infectious disease and non-infectious disease?
Infectious disease is caused by a pathogen that is passed from one organism to another (i.e flu). Non-infectious disease can’t be passed on; not caused by pathogens (i.e diabetes).
What can cause symptoms of a disease? (i.e runny nose, coughing)
Tissue destruction/obstruction, blocked transport systems, malnutrition.
What causes non-infectious disease?
Genetics (i.e sickle cell)
Nutritional issues (i.e vitamin deficiencies, high blood pressure)
Environmental exposure (i.e too much exposure to toxic chemicals, radiation and stress)
Describe pathogenic organisms.
There are two groups; primary pathogens, opportunistic pathogens. They cause disease to an organism. Can include prions, viruses, bacteria, fungi, protists and parasites.
Primary pathogens?
Cause disease at the time they are present.
Opportunistic pathogens?
Only causes disease when the host’s defences have been weakened, for example, poor nutrition.
Stages of disease?
- Exposure to pathogen (infection)
- Incubation period (pathogens multiply)
- Infectious period (symptoms show)
- Infectious period ends
- Recovery
EXTRA! What are prions?
Parasitic proteins. It gets ingested, and basically confuses all the nerve endings in the brain. Its not cureable. Can be caused by raw meats, untreated product.
Describe the antigenic drift.
Some viruses cause random genetic changes to cause minor changes to antigens on their surface. Its what can cause different strains of a virus (i.e COVID strains, flu).
Why don’t antibiotics work on viruses?
Viruses aren’t living organisms. They are just a piece of DNA or RNA. They cannot be killed without killing the host cells.
Describe bacteria.
They can be unicellular or multicellular,aerobic or anaerobic.
Deduce between exotoxins and endotoxins.
A toxin in bacteria are exotoxins. They are released from bacteria and can be dangerous. Endotoxins are produced inside the cell and are released when the cell is ruptured.
Describe fungi.
Not all fungi are dangerous; only some are pathogenic. There are three groups that effect humans: Mould, true yeasts and fungi-like yeasts.
Describe protists.
They are very diverse, ranging from multicellular photosynthetic organisms (i.e seaweed) to pathogenic unicellular organisms.
