Protoctists, bacteria and viruses

Protoctists, bacteria and viruses

1. Protoctists

   • single celled and microscopic
   • some are more similar to animal cells

2. bacteria

   • single celled, microscopic
   • DONT have nuclei
   • circular chromosome of dna
   • some can photosyntheise
   • feed off organisms, dead or alive

3. Viruses

   • classed as particles, smaller than bacteria
   • can only reproduce inside living cells so are parasites
   • infect all types of organisms
   • come in lots of sizes and shapes
   • do not have cellular structure, they have a protein coat around genetic material, either DNA OR RNA

4. pathogens

   • some organusms are pathogens, this means that they cause diesease,
   • examples are plasmodium(protoctist) which causes malaria; pneumococcus(bacteria) which causes pneumonia and influenza(virus) which causes flu