Kingdom Archaebacteria and Kingdom Eubacteria

Eubacteria / Archaebacteria



Fungi / Plantae


Life Cycles

General Characteristics


  • prokaryotic
  • heterotrophs
  • live in salt lakes, hot springs, animal guts



1. extreme halophiles - an organism that requires a salty environment

2. methanogens -

  • common name of organisms requiring completely anaerobic conditions for growth
  • produce methane gas as a catabolic product
  • they are found in the bovine stomach, swamp mud, and other environments where oxygen is not present. 
  • There are four taxonomic orders: methanobacteriales, methanococcales, methanomicrobiales, and methanosarcinales

3. extreme thermophiles - organisms requiring high temperatures for normal development, as certain bacteria.



  • simple organisms lacking nuclei (prokaryotic)
  • either heterotrophs or autotrophs
  • all can reproduce asexually
  • live nearly everywhere




1. bacteria -

  • Any of the unicellular prokaryotic microorganisms which vary in terms of morphology, oxygen and nutritional requirements, and motility
  • They can be free-living, saprophytic, or pathogenic in plants or animals.

2. cyanobacteria -

  • A photosynthetic bacterium generally blue-green in color and in some species capable of nitrogen fixation.
  • Cyanobacteria were once thought to be algae.

Anatomical and Physiological Characteristics
  • Eubacteria and Archaebacteria is mainly asexual by binary fission.
  • Their abundance is largely a result of their rapid rate of reproduction.
  • Eubacteria and archaebacteria display a variety of modes of nutrition
  • Eubacteria take part in many ecological processes, e.g., decomposition, nitrogen fixation, and oxygen production.
  • They are pathogens.

Respiration and Nutrition

  • obligate aerobes - bacteria that require oxygen for respiration
  • obligate anaerobes - bacteria that conduct respiration processes in the absence of oxygen
  • facultative anaerobes - bacteria that prefer environments with oxygen, but can live without oxygen
  • When oxygen is absent, both obligate and facultative anaerobes obtain energy from fermentation.
Reproduction and Growth
  • Eubacteria and archaebacteria reproduce asexually by binary fission.

o       The single strand of bacterial DNA replicates, resulting in identical genetic material being transferred to each new cell.

o       Following replication of the genetic material, the bacterium produces a cross wall and divides into two identical cells which may separate or remain attached.

  • Sexual reproduction is not common, but conjugation does occur among some intestinal bacteria

o       In conjugation, two conjugal bacteria, referred to as donor and recipient, make cell-to-cell contact by means of a cytoplasmic bridge.

o       Plasmids are transferred from the donor to the recipient to form new DNA with an altered set of characteristics.

  • Some bacteria of the bacillus type have adapted to survival during unfavourable conditions by forming resting cells known as endospores.

o       Endospores are genetic material encapsulated by a thick, resistant cell wall.