2. Bacteria
Bacteria form a group of organisms primitive nuclei,
treated by man without seeing them, it has been
known to cause disease and used some of them in
various fermentation processes . And the discovery of
the microscope had a great impact on her
identification. Definition of bacteria:
They are unicellular microorganisms that have
everything they need to do all the basic functions of
life.
3. General properties of bacteria
1 )primitive micro-organisms nuclei.
2) featuring simple structure It is formed from a cell wall
and membrane surrounding the cytoplasm that contains a
single ring chromosome DNA
3) its wall hardness comes for the presence of a
polypeptide
4) multiply by simple binary fission
5) in order for bacteria cells to be clearly seen under a
microscope, we need to use different
4. Forms of bacteria
A) spherical bacteria :They may be single or chain-
shaped, such as pneumonitis bacteria, or bilateral,
quadruple, or more irregular clusters .
B) Bacillus bacteria :They may be single, chain-
shaped or receptive in shape, such as cholera
bacteria .
C) spiral bacteria :They are the largest, like the
bacteria of syphilis .
5. Types of bacteria based on their
way of nutrition
A) Autotrophic: are bacteria that make food
needs for them from their primary sources
may use the light energy so called photo
autotrophic or use chemical energy so
called chemo autotrophic .
B) B) Heterotrophic: non-self-feeding bacteria
usually live within living organisms
6. Benefits of bacteria
- Analyze the bodies of dead creatures to feed on
them.
- Fixation of atmospheric nitrogen in the root
cells of certain plants.
- - Used in the manufacture of a lot of food such
as: vinegar, some types of cheese, turn milk
into milk
- Extraction of primitive starch from the roots of
plants.
7. Author: Dr.. Mohamed El-Sawy
Mohamed Mubarak
Dr.. Abdelwahab Mohamed Abdelhaf
Dr.. Rawya Fathi Jamal
Publication year 2005
Book name: The world of bacteria
Publisher: Osiris Library
