A) Chief distinguishing characteristics of prokaryotes be:
1. Their genetic material (DNA) is not enwrap within a membrane; it is maven circular chromosome.
2. They deprivation other membrane-enclosed organelles.
3. Their DNA is not associated with histone proteins.
4. Their cell skirts almost constantly contain the complex polysaccharide peptidoglycan.
5. They usually divide by binary fission.
B) Prokaryotes include bacteria (eubacteria) and archaea (archaebacteria). The majority of known bacteria,
including the photosynthesizing cyanobacteria, argon included in the eubacteria.
C) Prokaryotic cell structure
1. There are a great many sizes and shapes among bacteria. Most bacteria contrive from 0.2-2.0 um in
diameter, and from 2-8 um in length.
2. They have a few basic shapes: spheric coccus, rod-shaped bacillus, and spiral.
A. Cocci that remain in pairs after dividing are called diplococci; those that remain in groups of
four are known as tetrads; those that remain in cubelike groups of eight are called
sarcinae; those that contour grapelike clusters are called staphylococci; those that remain
attached in chainlike patterns are called streptococci.
B. Most bacilli come out as single rods. Diplobacilli appear in pairs, and streptobacilli occur in
chains.
C.
Spiral bacteria have one or more twists. Bacteria that look like veer rods are called vibrios.
1) Others, called spirilla, have a spiraling shape, like a corkscrew, and fairly rigid bodies.
2) Another group of spirals are helical and flexible; they are called spirochetes.
3. Among the structures external to the prokaryotic cell wall are the glycocalyx, flagella, axial filaments,
fimbriae, and pili.
A. The glycocalyx can take the form of a capsule (organized and firmly attached to cell wall), or
a grime layer(unorganized and loosely attached to the cell wall).
1) Capsules often protect unhealthful bacteria from...If you want to get a full essay, recite it on our website: Ordercustompaper.com
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