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Figure 9 – Pseudomonas bacteria are Reproduction in Bacteria
decomposers found in the soil, where they
recycle dead plant material. All living things reproduce. This is
The last groups of bacteria get the only way to ensure the
energy from organisms that are organisms continued survival.
still alive, and depend on these Bacteria reproduce asexually.
organisms to survive. This means that a single “parent”
organism produces offspring on
Mutualistic bacteria get their their own.
energy in ways that help another
organism. For example, some In the case of bacteria, a process
bacteria live in the roots of called binary fission is used. In
legumes, including pea plants. The binary fission, the DNA in the
bacteria make the nitrogen the pea nuceleoid region and plasmids
plants need and the pea plants double, and the bacterium splits
provide a place for the bacteria to into two identical copies. If
live. everything happens the way it’s
supposed to, the two new bacteria
Other bacteria, called parasitic will be identical to the original
bacteria, hurt the organism they bacterium.
are getting help from. For
example, some bacteria cause These bacteria can then split again
illness. We will talk about ways to increase the number of bacteria
bacteria can be helpful or harmful in the population. Through binary
a little later. fission, bacteria reproduce very
quickly. Some populations can
double their size in less than ten
minutes!
How Bacteria Help
Bacteria have a bad reputation.
Walk down the cleaning aisle of
any store and you’ll see rows and
Figure 9 – Ryzobium bacteria (left) have a
mutualistic relationship with legumes, but rows of products promising to kill
the tuberculosis bacterium (right) is them. There are definitely some
parasitic. bacteria that cause problems for
people, and we’ll talk about them
soon, but we are going to start off
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