Kingdom Monera
Basic information:
Kingdom Monera includes all
prokaryotic organisms with noncellulosic (Polysaccharide and amino acid) cell
wall. Bacteria are the sole members of the Kingdom Monera.
Habitat:
They are found everywhere i.e., in very hot or cold region or inside human
body.
Characters:
The main characters of kingdom Monera are:
·
The members of
kingdom monera are prokaryotic.
·
Cell Wall is
Noncellulosic (Polysaccharide and amino acids)
·
Nuclear membrane is
absent.
·
Body organisation is
Cellular.
·
Mode of nutrition is
Autotrophic (Chemosynthetic and photosynthetic) and Heterotrophic (Saprophytic
and Parasitic)
Bacteria are grouped under four categories
Based on their shapes:
1. cocci: Coccus (pl.: cocci) are spherical, ovoid or generally
round shaped bacteria. If two coccus were attached together they were called
diplococci; rows of such bacteria are called Streptococci and if bacteria are
attached in groups or clusters they are called Staphylococci. Sarcina is the
condition when cocci are arranged in cubes of eight.
2. Bacilli: Bacillus (pl.: bacilli) are cyllindrical or rod-shaped
bacteria. These bacteria were widely found in soil and water. These bacteria
were also found in the gastrointestinal tract of ruminants and humans.
3. Vibrio: Vibrium (pl.: Vibrio) are comma shaped bacteria. They are commonly found in aquatic and marine environment.
4. Spirillum: Spirillum (pl.: spirilla) are the spiral,large, elongate and rigid bacteria. They are usually found in stagnant freshwater rich in organic matte
Kingdom Monera
is divided into two groups
1.
Archeabacteria
2.
Eubacteria
1. Archeabacteria: These are the ancient and special bacteria since they
live in some of the most harsh habitats suh as extreme salty areas
(halophiles), hot springs (thermoacidophiles) and marshy areas (methanogens).
These are called ancient bacteria because these are one of the oldest living
organisms known on Earth.
Characteristics of Archeabacteria:
Here are listed some
important characteristics of Archeabacteria:
·
Most primitive
prokaryotes.
·
Can live under
extreme harsh conditions.
·
Known as living
fossils.
·
They can be obligate
anaerobes or facultative anaerobes.
·
used in the
production of gobar gas and cellulose fermentation.
·
Absence of
peptidoglycan in cell wall.\
2. Eubacteria: These are prokaryotic microorganisms consisting of a
single cell lacking a nucleus and containing DNA is a single circular chromosome.
Eubacteria is also known as true bacteria. They are characterised by the
presence of a rigid cell wall, and if motile, a flagellum. The cyanobacteria
(also referred to as blue-green algae) have chlorophyll a similar to green
plants and are photosynthetic autotrophs. Eubacteria can be either gram-negative
or gram-positive.
Characteristics of Eubacteria:
·
Microscopic in nature.
·
Cell wall is made up
of peptidoglycan.
·
They are unicellular.
·
Sexual reproduction
is absent.
·
Motile bacteria
possess flagella.
·
Some of these
organisms can fix atmospheric nitrogen in specialised cells called heterocysts,
e.g., Nostoc and Anabaena.
·
They play a great
role in recycling nutrients like nitrogen, phosphorous, iron and sulphur.
Economic importance:
Ecologically, monerans are major decomposers in the world’s
ecosystems. Many have symbiotic relationships, some have mutualistic, and some
have parasitic. They can be used in food production, in the manufacture of
artificial snow, in mining, and in biotechnology in the manufacture of
pharmaceuticals.
