Chapter 27: Bacteria & Archaea Flashcards
What are prokaryotes?
Organisms who’s cells lack a nucleus and other membrane-bound organelles
Prokaryotes are masters of ________ and _________.
adaptation, metabolism
What does it mean to be masters of adaptation?
An organism can thrive almost everywhere (Including places too acidic, salty, cold, hot etc.)
What does it mean to be masters of metabolism?
Organisms have numerous methods for obtaining carbon and energy
Prokaryote cells are _________ (smaller/bigger) than many eukaryote cells.
smaller
Define unicellular
Organisms that are made of only one cell (All functions are carried out within one cell)
Are prokaryotes unicellular or multicellular?
Unicellular
What are the 3 different morphologies of bacteria?
Coccus Bacillus Spirillum
What do coccus bacteria look like?
Sphere shaped
What do bacillus bacteria look like?
Rod shaped (Oblong oval cheeto thing)
What do spirillum bacteria look like?
Twists like a spiral (Zigzag thingy)
In eukaryotes with cell walls (plants), the walls are usually made up of cellulose or chitin. What do bacterial cell walls contain?
Peptidoglycan
What is peptidoglycan?
A polymer consisting of sugars and amino acids that form a mesh-like layer outside the plasma membrane of bacteria, forming a cell wall.
There are two types of cell walls, what are they?
Gram-positive (Gram +) Gram-negative (Gram -)
Describe a Gram-positive cell wall.
- Purple after staining
- Retains the crystal violet colour after staining
- Single layered, straight cell wall
- Rigid (less elastic)
- Large amount of peptidoglycan
- No outer membrane
- Not pathogenic to humans/animals
Describe a Gram-negative cell wall.
- Pink after staining
- Clear (does not retain the crystal violet colour) after staining
- Two layered, wavy cell wall
- Elastic (less rigid)
- Smaller amount of peptidoglycan
- Outer membrane present
- Pathogenic to humans/animals
Which picture is Gram-positive and Gram-negative?
A is Gram-positive
B is Gram-negative
Flagella affect ______.
motility
Some prokaryotes have specialized membranes that perform metabolic functions. What are the two prokaryotes?
- Aerobic Prokaryotes
- Photosynthetic Prokaryotes (cyanobacteria)
What specialized membrane do Aerobic Prokaryotes have?
Infolding of the plasma membrane
What specialized membrane do Photosynthetic Prokaryotes have?
Thylakoid membranes (similar to those in chloroplasts)
If you see a cell wall and it has peptidoglycan in the cell wall, it must be ________.
Bacteria