pathogens and communicable disease Flashcards
what are vectors?
- carries pathogens between organisms
- eg water and insects
describe bacteria
- prokaryotes= no membrane bound organelles or nucleus
- only pathogenic bacteria will cause communicable disease
- reproduce by binary fission
- produce toxic waste
What type of cells can viruses use as their host cell?
- all types of eukaryotes
- viruses called bacteriophages can also use prokaryotes
What is the difference between protoctista and protista?
- protoctista= includes multicellular organisms
- protista= unicellular
What are protoctista?
- eukaryotic organisms
- wide variety of feeding methods
- single celled
- most are not pathogenic
- pathogenic are parasites - transmitted through vector
What is meant by pathogenic protoctista being parasitic?
use the people or animals they infect as their host organism
What are fungi?
eukaryotic organisms, that are often multicellular, but sometimes single celled
- pathogenic are parasitic, releasing enzymes to host tissue
Why do fungi feed on dead and decaying matter?
They have to digest food to obtain their nutrients, so they secrete digestive enzymes into the food source and absorb the nutrients
What are parasitic fungi?
- feed of living plants and animals
- these ones cause communicable disease
How does fungi pathogens kill plants?
- infect the plants
- stopping photosynthesis
How have fungi adapted so they can spread rapidly and widely through crop plants?
produce millions of tiny spores which can spread huge distances
Give 4 ways in which pathogens can attack the cells of their host organism and cause disease?
- take over cell metabolism, as viral genetic material is inserted into host cell DNA
- take over cell and digest contents
- completely digest living cells and destroy them
- produce toxins which poison and damage host cells, some toxins break down cell membranes or inactivate enzymes or prevent cell division
give an example of a bacteria in animals
tuburculosis
give an example of bacteria in plants
ring rot
give 2 examples of viruses in animals
HIV
influenza
