Monera and viruses Flashcards
what is monera and what is it divided into?
Monera are prokaryotic and unicellular organisms. have a rigid cell wall, divided into archaebacteria and eubacteria further divided into cyano bacteria
who discovered bacteria?
Anton van Leeuwenhoek
what is coccus and the different types?
Spherical shaped bacteria
Diplococcus(pairs)
Staphylococcus(Cluster of cells)
Streptococcus(Filaments or strings)
what is the rod shaped bacteria?
Baccilus, 2 types
Diplobacillus(pairs)
Streptobacillus(Filaments)
what are the other 2 shapes of bacteria?
-Spirillum(Spiral coiled) and Vibrio(Curved)
what are the cell walls of bacteria made of? and what chains?
- Made of peptidoglycan or murein
- amino acid chains or polysaccharide chains.
what is added to bacteria to check if they are gram positive or negative?
- Crystal violet is grams stain used on bacteria
- treated with alcohol and KI,
- retain the blue colour they are gram positive
- Dont retain colour gram negative
what are the differences between a gram positive and gram negative bacteria?
- Gram positive: have thick layer of peptidoglycan wall
- Gram negative: have thin layer of peptidoglycan wall pressed between 2 membranes
how do bacteria’s asexually reproduce?
bacteria’s reproduce by binary fusion where the bacteria splits into 2 equal halfs and the dna replicates.
what is conjugation?
transfer of DNA between two different strains of bacteria
A bridge is formed between the mating cells, the DNA(plasmid) gets donated from the male to female responsible for cell membrane called sex pilli
describe spore formation give 2 examples
spore formation is preservation of vital parts of cell, takes place in un favorable conditions. eg botulism and tetanus.
what is archea bacteria
they are the oldest of fossils or ancient bacteria.
what are viruses?
viruses are non-living intercellular parasites that have very less organelles but replicate themselves.
who discovered viruses and how!?
D.J Ivanovsky
-noticed yellow and green mosaic pattern in plants
he found out it was infectious to others and called it contagium vivum fluiduim
who were the other scientists?
Dutch M.W beierink give the term virus
W.M Stanley crystalized them.
