Bacteria and Archea Flashcards
How do you tell Bacteria apart?
Shape
Chemical test - Gram positive/negative
Metabolism
What are the three shapes for bacteria?
- Spheres (cocci)
- Rods (bacilli)
- Spirals
Gram Positive
- Blue or Red
Gram Negative
Pink
Why do gram negative not stain?
Outer membrane made of lipopolysaccharide (endotoxin) that prevents staining
Exotoxins
proteins secreted by living bacteria into the surrounding environment.
– They can cause damage to host cells and tissues even if the bacteria that produce them are not present.
Endotoxins
- part of outer membrane of Gram Negative Bacteria
- released only when the bacteria die and their cell walls break down
How do bacteria adapt?
- their ability to pass on resistance genes
- replicate and multiply quickly
Transformation
process where a prokaryotic cell can take up and incorporate foreign DNA from the surrounding environment.
Transduction
the process by which genes are transferred between bacteria by bacteriophages, which are viruses that infect bacteria.
Conjugation
a process where genetic material is transferred between prokaryotic cells, often through direct cell-to-cell contact.
Obligate Anaerobes
poisoned by O2 and live by fermentation or use substances other than O2 for anaerobic respiration
Facultative Anaerobes
use O2 if it is present or carry out fermentation or anaerobic respiration if it is not
Photoautrophs
use light
Chemoautotrophs
organisms that obtain energy by oxidizing inorganic substances
- use c02 as their main energy
