The document discusses bacterial morphology and classification based on cell shape. It notes that most bacteria are between 0.2-1.5 um in diameter and 2-8 um in length. It describes the different shapes bacteria can take based on how their cells divide, including diplococci, streptococci, tetrads, and sarcinae for cocci, and single rods, diplobacilli, and streptobacilli for bacilli. Some less common shapes mentioned are coccobacilli, stella, and rectangular haloarcula.

3. **Most bacteria are 0.2 um in diameter
and 2-8 um in length.
**Bacteria of medical importance
•0.2 – 1.5 µm in diameter
•3 – 5 µm in length
www.shurgard.co.uk

4. S. pneumoniaeLactobacillus sp Fusobacterium
polymorphum

7. *Cocci that remain in pairs after
dividing are called diplococci.
*Cocci that remain in chains after
dividing are called streptococci.
*Cocci that divide in two planes and
remain in groups of four are called
tetrads.
*Cocci that divide in three planes and
remain in groups cube like groups of
eight are called sarcinae.
*Cocci that divide in multiple planes
and form grape like clusters or sheets
are called staphylococci.

8. **Since bacilli only divide across their
short axis there are fewer groupings.
•Most bacilli appear as single rods.
Diplobacilli appear in pairs after
division.
•Streptobacilli appear in chains
after division.
• Some bacilli are so short and fat
that they look like cocci and are
referred to as coccobacilli.

9. Stella are star-shaped.
Haloarcula, a genus of halophilic
archaea, are rectangular.

17. 1. http://classes.midlandstech.edu/carterp/courses/bio225/chap04
/lecture2.htm
2. http://examples.yourdictionary.com/examples-of-bacteria.html
3. faculty.ccbcmd.edu/courses/bio141/lecguide/unit1/shape/shape.h
tml
4. science.kennesaw.edu/~jhendrix/ahmicro/shapes.pdf
5. study.com/.../bacterial-cell-morphology-and-classification-
definition