bacteria discussion
Download
Skip this Video
Download Presentation
Bacteria Discussion

Loading in 2 Seconds...

play fullscreen
1 / 17

Bacteria Discussion - PowerPoint PPT Presentation


  • 99 Views
  • Uploaded on

Bacteria Discussion. September 7, 2012 (Really). Basic Characteristics Single celled No membrane-bound organelles Nucleoid region Microscopic. I. Prokaryotes. B. How do we identify different types of prokaryotes?. Identified by the following: Shapes

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Bacteria Discussion' - kizzy


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
bacteria discussion

Bacteria Discussion

September 7, 2012

(Really)

i prokaryotes
Basic Characteristics

Single celled

No membrane-bound organelles

Nucleoid region

Microscopic

I. Prokaryotes
b how do we identify different types of prokaryotes
B. How do we identify different types of prokaryotes?
  • Identified by the following:
    • Shapes
    • Chemical nature of their cell walls
    • The ways they move
    • The ways they obtain energy
c basic structure
Cell wall – protects the cell & gives it shape.

Outer membrane – protects the cell against some antibiotics (only present in some)

C. Basic Structure
c basic structure cont
C. Basic Structure (cont.)
  • Cell membrane – regulates movement of materials into & out of the cell; contains enzymes important to cellular respiration.
  • Plasmid – circular piece of DNA that contains some genes obtained through genetic recombination.
  • Capsule & Slime layer – protect the cell & assist in attaching the cell to other surfaces.
slide7

• Cell Arrangements

– Diplo – cells are paired

– Staphylo – cells are in

grape-like clusters

– Strepto – cells are in

long chains

ii shapes groupings of bacteria
II. Shapes & Groupings of bacteria

Three basic shapes of bacteria

Bacillus = rod shape

Coccus = round or spherical shape

Spirilla = spiral shape

b cell groupings
B. Cell Groupings
  • Diplo – cells are paired
  • Staphylo – cells are in grape-like clusters
  • Strepto – cells are in long chains
iii cell wall types
III. Cell wall types
  • Two different types of cell walls are found in eubacteria
    • Bacteria cells containing peptidoglycan
    • Bacteria with an outer layer of lipid and carbohydrate molecules
  • Gram staining helps to tell them apart using two different types of dye
    • Violet - primary stain
    • Red - counterstain
iv growth reproduction
IV. Growth & Reproduction
  • Binary Fission: bacterium doubles in size, it replicates its DNA and divides in half
    • Each daughter cell is a clone of the parent
  • Is this sexual or asexual reproduction?
    • Asexual
iv growth reproduction cont
IV. Growth & Reproduction (cont.)
  • Types of Genetic Recombination
    • Conjugation: process by which two living bacteria bind together and one bacterium transfers genetic information to the other
    • Transformation: occurs when bacterium binds to and then takes up DNA released by dead bacteria
    • Transduction: viruses carry portions of DNA from one bacterium to another
iv growth reproduction cont1
IV. Growth & Reproduction (cont.)
  • Endospore: thick-walled, dehydrated structures inside bacterium
    • Protects the cell against harsh environmental conditions, such as heat and drought
    • May allow the bacterium to survive for thousands of years
    • Not for reproduction, but for survival
v examples of bacteria
V. Examples of Bacteria
  • Bacillus cereus
    • Found in soil
    • Straight rods
    • Arranged singly or in pairs
    • Cause of a lot of food borne illnesses
v examples cont
V. Examples (cont.)
  • Aquaspirillumserpens
    • Found in fresh water
    • Spiral shaped
    • Arranged singly
v examples cont1
V. Examples (cont.)
  • Escherichia coli (E. Coli)
    • Straight rods
    • Arranged singly or in pairs
    • Named after pediatrician who discovered it
    • Digest food in your intestines (benefit to us)
    • Some strains are very harmful and can lead to food borne illnesses
v examples cont2
V. Examples (cont.)
  • Staphylococcus epidermidis
    • Epidermis = skin
    • Spherical shape
    • In clusters
    • Usually not pathogenic
  • Staphylococcus aureus
    • Spherical shape
    • In clusters
    • Most common type of staph infections in humans
    • MRSA: Methicillin-resistant S. aureus
      • Highly resistant to antibiotics
ad