Diseases Test T2 Flashcards
(15 cards)
What is disease?
An organism that is growing and carrying out life’s processes ‘with ease’ is said to be in a good state of health or healthy. ‘Dis-ease’ results if good health breaks down.
What is infectious disease?
What is non-infectious disease?
Disease that cannot be transmitted tor other organisms. Either genetic or lifestyle diseases
What is a “lifestyle” disease?
Disease caused by long-term “unhealthy” habits. eg. diabetes or heart disease.
What is genetic disease?
Hereditary disease that is passed on to offspring. Inherited condition caused by a change in DNA. EG: pulmonary fibrosis
What is a pathogen?
Agent that causes infectious disease. Can be living eg. parasite or non-living eg. virus
What are the characteristics of a pathogen?
- have ways of increasing numbers
- need a food source from in between cells
- live on or enter a host to replicate or obtain nutrients
- have adaptations
- have ways of avoiding the immune system
What are the five main pathogens?
Bacteria, protists, viruses, parasites, and fungi.
What are the characteristics of bacteria?
Unicellular prokaryotes. Upon entering the host’s bloodstream, they move into (infect) tissues where they may reside for a period of time. Bacteria release chemical’s that disrupt cell function (toxins). They divide (by binary fission) to produce large numbers of new bacteria that damage tissues causing disease. EG: tooth decay, food poisoning, tuberculosis (TB), and cholera.
What are the characteristics of fungi?
Unicellular organism (yeast) or multicellular (mould) eukaryotes. Mould: if left in contact with warm and moist skin, they increase in numbers causing the skin to crack = bacterial infection = inflammation. EG: athletes foot
What are the characteristics of viruses?
Non-living, acellular infectious agents. Viruses may enter cells through the cell membrane. Once it has infected the host cell, the virus may use it to produce new viruses (viral replication). These new viruses soon leave the host cell where they can infect more cells, either in the same body or in a new host organism. Some viruses, however, remain dormant in the host cell for a period before the replication processes begins. EG: influenza, Covid-19
What are the characteristics of protists?
Unicellular, non-fungi eukaryotes. It can restrict nutrient absorption and infect cells. EG: Malaria
What are the characteristics of parasites?
An organism that lives on or in another organism (host). Harm the host, but not enough to cause death.
Describe the structure of a virus
A virus is genetic material (DNA or RNA) enclosed in a lipid membrane ‘coat’ with proteins on its surface.
