Reproduction Techniques in Monera Kingdom - agranda
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Transcript Reproduction Techniques in Monera Kingdom - agranda
REPRODUCTION TECHNIQUES IN
MONERA KINGDOM:
By:Alessio,Giosue and Alexandra
Most prokaryotes reproduce asexually through
binary fission. This is where the cell makes a
duplicate of itself and one DNA molecule passes
into a newly formed cell. These two cells are
genetically identical. Binary fission does not
allow for the bacteria to acquire genetic
diversity. This diversity is needed for bacteria to
withstand changing environments. Bacteria
have the ability to shuffle genes through several
processes. These processes include
transformation, conjugation, and transduction
Unlike eukaryotic cells, which divide by mitosis
or meiosis, eubacteria reproduce by binary
fission. In this process, the genetic material is
replicated, and the two copies move to separate
nucleoid regions. Next, the plasma membrane
pinches inward, producing two equal daughter
cells. While these daughter cells are completely
independent of each other, in some species they
remain together, forming colonies and filaments.
Binary fission can take place very rapidly, on the
order of about one split every 20 minutes,
accounting for the amazing replicative ability of
eubacteria.
EUBACTERIA
Asexual reproduction (by binary fission) is the
only method of reproduction among bacteria,
however this only increases bacterial numbers
not their genetic variation. Genetic variation in
bacteria does occur and is accomplished by 4
methods. Three methods are by obtaining genes
from the environment or other bacteria. The
fourth method is simply by mutation
Some bacteria can be photosynthetic, using H2S
rather than H2O, as a source of electrons, but
most are heterotrophic, absorbing nutrients from
the surrounding environment.
Microscopic examination of bacterial cels reveals
that most bacteria can be classified according to
three basic shapes: bacilli (rods), cocci (spheres),
and spirilla (spirals, or corkscrews).
ARCHAEBACTERIA
Archaea,like bacteria are prokaryotes. They
doesn’t have any cell nucleus or any other
organelles in their cells.
In the past they were like an unusual group of
bacteria called Archaebacteria, but Archaea have
an independent evolutionary history and many
differences in their biochemistry, now they are
classified as a separate domain in the threedomain system.
Generally, bacteria and Archae are very similar
in size and shape.
Archaebacteria reproduce asexually and divide
by binary fission, fragmentation or budding,
meiosis does not occur, cause meiosis doesn’t
occur every species of Archae will have the same
genetic material.
Spores are made by eukaryotes and bacteria but
they doesn’t form in the known bacteria.
Some species of Haloarchaea grow as different
types of cell, including thick-walled structures
that can resist the osmotic shock that allow the
Archae to survive in water at low concentrations
of salt, but these are not reproductive structures
so these help them disperse to different habitats.
Archae are part of the systems on Earth that
have the work to recycle elements like carbon,
nitrogen and sulfur in the ecosystems.
Archae can also contribute to the changes that
humans cause in the environments, that’s why
its so important that Archae reproduces.
Archaebacteria is the oldest living organisms and
can be found in the most extreme environments.
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