Anatomy of
Prokaryotic Cells
Dyzza Lei L. Albarico
Julian Philip A. Soriano
Shaina Mavreen D. Villaroza
What are Prokaryotic Cells?
Prokaryotes are single-celled organisms that are
the earliest and most primitive forms of lif...
Prokaryotes do not have a
nucleus, mitochondria, or any other membrane-
bound organelles. In other words, neither their
D...
Cell Structure
 Capsule - Found in some bacterial cells, this
additional outer covering protects the cell
when it is engu...
Cell Structure
 Cell Membrane or Plasma
Membrane - Surrounds the cell's
cytoplasm and regulates the flow of
substances in...
Cell Structure
 Flagella - Long, whip-like protrusion
that aids in cellular locomotion.
 Ribosomes - Cell structures
res...
Cell Structure
Cell Shape
 Prokaryotes appear in 3 basic shapes:
1. Coccus – Spherical shaped
(plural,Cocci)
2. Bacillus – Rod shaped (p...
Coccus
 The cocci are spherical or oval bacteria
having one of several distinct arrangements
based on their planes of div...
Coccus
c. Division in three planes produces
a sarcina arrangement.
1.sarcina: cocci in arranged cubes of 8
d. Division in ...
Coccus Shape
Spirillum
 Spirals come in one of
three forms, a vibrio, a spirillum, or
a spirochete.
a) vibrio: a curved or comma-shape...
Bacillus
 Bacilli are rod-shaped bacteria. Bacilli all
divide in one plane producing
a bacillus, streptobacillus, or cocc...
Bacillus Shape
Example:
Staining Techniques
 Simple Stains
◦ Differential Stains
1. Gram Staining
2. Acid-fast Stain
◦ Special Stains
1. Endospor...
Simple Staining
 Staining can be performed with basic
dyes such as crystal violet or
methylene blue, positively charged
d...
Differential Staining
 Gram Staining
This differential technique separates bacteria into
two groups, Gram-positive bacter...
Figure 1. The Gram stain
procedure used for differentiating
bacteria into two groups.
•Acid Fast Stain
This technique differentiates species
of Mycobacterium from other bacteria.
Heat or a lipid solvent is us...
Special Staining
 Negative Staining for Capsule
Capsule staining uses a mixture of the bacteria
in a solution containing ...
Example of Negative Staining
Endospore Staining
◦ An endospore is a special resistant
dormant structure formed within a cell that
protects a bacterium ...
Example of Endospore
Staining
Flagella Staining
A tedious and delicate staining
procedure uses a mordant and the stain
carbolfuchsin to build up the dia...
Example of Flagella Staining
Anatomy of prokaryotic cells
Anatomy of prokaryotic cells
Anatomy of prokaryotic cells
Upcoming SlideShare
Loading in …5
×

Anatomy of prokaryotic cells

602 views

Published on

Published in: Technology, Education
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
602
On SlideShare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
33
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Anatomy of prokaryotic cells

  1. 1. Anatomy of Prokaryotic Cells Dyzza Lei L. Albarico Julian Philip A. Soriano Shaina Mavreen D. Villaroza
  2. 2. What are Prokaryotic Cells? Prokaryotes are single-celled organisms that are the earliest and most primitive forms of life on earth. They have no true nucleus as the DNA is not contained within a membrane or separated from the rest of the cell
  3. 3. Prokaryotes do not have a nucleus, mitochondria, or any other membrane- bound organelles. In other words, neither their DNA nor any of their other sites of metabolic activity are collected together in a discrete membrane-enclosed area. They have a single, circular chromosome. They have cell walls containing peptidoglycan Their DNA is not associated with Histones.
  4. 4. Cell Structure  Capsule - Found in some bacterial cells, this additional outer covering protects the cell when it is engulfed by other organisms, assists in retaining moisture, and helps the cell adhere to surfaces and nutrients.  Cell Wall - Outer covering of most cells that protects the bacterial cell and gives it shape.  Cytoplasm - A gel-like substance composed mainly of water that also contains enzymes, salts, cell components, and various organic molecules.
  5. 5. Cell Structure  Cell Membrane or Plasma Membrane - Surrounds the cell's cytoplasm and regulates the flow of substances in and out of the cell.  Pili - Hair-like structures on the surface of the cell that attach to other bacterial cells. Shorter pili called fimbriae help bacteria attach to surfaces.
  6. 6. Cell Structure  Flagella - Long, whip-like protrusion that aids in cellular locomotion.  Ribosomes - Cell structures responsible for protein production.  Plasmids - Gene carrying, circular DNA structures that are not involved in reproduction.  Nucleiod Region - Area of the cytoplasm.
  7. 7. Cell Structure
  8. 8. Cell Shape  Prokaryotes appear in 3 basic shapes: 1. Coccus – Spherical shaped (plural,Cocci) 2. Bacillus – Rod shaped (plural, Bacilli) 3. Spirillium – Spiral known
  9. 9. Coccus  The cocci are spherical or oval bacteria having one of several distinct arrangements based on their planes of division. a. Division in one plane produces either a diplococcus or streptococcus arrangement. 1. diplococcus: cocci arranged in pairs 2.streptococcus: cocci arranged in chains b. Division in two planes produces a tetrad arrangement. 1.a tetrad: cocci arranged in squares of 4
  10. 10. Coccus c. Division in three planes produces a sarcina arrangement. 1.sarcina: cocci in arranged cubes of 8 d. Division in random planes produces a staphylococcus arrangement. 1.staphylococcus: cocci arranged in irregular, often grape-like clusters  An average coccus is about 0.5-1.0 micrometer (µm) in diameter.  (A micrometer equals 1/1,000,000 of a meter.)
  11. 11. Coccus Shape
  12. 12. Spirillum  Spirals come in one of three forms, a vibrio, a spirillum, or a spirochete. a) vibrio: a curved or comma-shaped rod b) spirillum: a thick, rigid spiral c) spirochete: a thin, flexible spiral  Spirals range in size from 1 µm to over 100 µm in length.
  13. 13. Bacillus  Bacilli are rod-shaped bacteria. Bacilli all divide in one plane producing a bacillus, streptobacillus, or coccobacillus ar rangement. a) bacillus: single bacilli b) streptobacillus: bacilli arranged in chains c) coccobacillus: oval and similar to a coccus  An average bacillus is 0.5-1.0 µm wide by 1.0-4.0 µm long.
  14. 14. Bacillus Shape
  15. 15. Example:
  16. 16. Staining Techniques  Simple Stains ◦ Differential Stains 1. Gram Staining 2. Acid-fast Stain ◦ Special Stains 1. Endospore Staining 2.Flagella Staining 3.Capsule Staining
  17. 17. Simple Staining  Staining can be performed with basic dyes such as crystal violet or methylene blue, positively charged dyes that are attracted to the negatively charged materials of the microbial cytoplasm.
  18. 18. Differential Staining  Gram Staining This differential technique separates bacteria into two groups, Gram-positive bacteria and Gram-negative bacteria. Crystal violet is first applied, followed by the mordant iodine, which fixes the stain .Then the slide is washed with alcohol, and the Gram-positive bacteria retain the crystal-violet iodine stain; however, the Gram- negative bacteria lose the stain. The Gram-negative bacteria subsequently stain with the safranin dye, the counterstain, used next. These bacteria appear red under the oil-immersion lens, while Gram-positive bacteria appear blue or purple, reflecting the crystal violet retained during the washing step.
  19. 19. Figure 1. The Gram stain procedure used for differentiating bacteria into two groups.
  20. 20. •Acid Fast Stain This technique differentiates species of Mycobacterium from other bacteria. Heat or a lipid solvent is used to carry the first stain, carbolfuchsin, into the cells. Then the cells are washed with a dilute acid-alcohol solution. Mycobacterium species resist the effect of the acid-alcohol and retain the carbolfuchsin stain (bright red). Other bacteria lose the stain and take on the subsequent methylene blue stain (blue). Thus, the acid- fast bacteria appear bright red, while the nonacid-fast bacteria appear blue when observed under oil- immersion microscopy.
  21. 21. Special Staining  Negative Staining for Capsule Capsule staining uses a mixture of the bacteria in a solution containing a fine colloidal suspension of colored particles to provide a dark background and then stain the bacteria with a simple stain such as safranin.
  22. 22. Example of Negative Staining
  23. 23. Endospore Staining ◦ An endospore is a special resistant dormant structure formed within a cell that protects a bacterium from adverse environmental conditions. Endospores cannot be stained by ordinary methods such as simple stains and gram staining. Malachite green the primary stain is applied to a heat fixed smear and heated to steaming for about 5 min. Then the perparation is washed for about 3o sec. with water to remove the malachite green from all the cells parts except for the
  24. 24. Example of Endospore Staining
  25. 25. Flagella Staining A tedious and delicate staining procedure uses a mordant and the stain carbolfuchsin to build up the diameters of the flagella until they become visible under the light microscope
  26. 26. Example of Flagella Staining

×