The Peokaryotic Cell Flashcards
What are the two groups of prokaryotic cells?
1.bacteria
2. Archaea
Three common shapes
Cocci, bacillus , helical
Cell wall function + description
Description : consists of many amino acids and peptidoglycan (an amino acid)
Function: stop cell from bursting
Gives cell characteristic shape
Supports cell
Slime capsule definition and function
Definition: polysaccharide covering around the cell membrane
Function: PROTECT against predators such as white blood cells
Allows prokaryotes to stick together sometimes, forming COLONIES
CELL MEMBRNE FUNCTION AND DEFINTION
Definition: PHOSPHOLIPID BILAYER
Function: Isolates contents from inside of the cell from contents outside
Controls what enters and exits the cell
DNA function and definition
- SINGLE COILED DNA STRAND, in the region of the cytoplasm called NUCLEOID
- carries GENETIC INFORMATION
Plasmids
-circular DNA fragments
- DNA code for only particular genes
RIBOSOMES
-structures made up of proteins and RNA
- PROTEIN SYNTHESIS (creation)
STORAGE GRANULES
- glycogen granules or lipid droplets
- food (energy) store
Photosynthetic llamalae
-sac like CAVITIES, containing photosynthetic pigments.
-PHOTOSYNTHESIS ( only photosynthetic prokaryotes)
Meso some
- Infolding on the cell membrane
- site for respiration
Flagellum
Rigid, shaped into a wave and no microtubules present
Movement
PILI
- pin like protein projections on the prokaryotes slime capsule or exterior
- allows the prokaryote to attach itself to other prokaryotes or to other surfaces in its environment.
Prokaryote four categories of nutrition
- Photoautotrophs - use photosynthesis
2.photoeterotrophs - light is their energy source - Chemolithotrophs -oxidising inorganic compounds
- Chemoheterobtrophs - obtain both energy and carbon from inorganic compounds
Gram stain test
The gram stain test reveals the complexity of a prokaryotes cell walls, tells us whether or not a bacterium will be resistant to antibiotics.
Gram positive bacterium characteristics
- thick layer of peptidoglycan
- colours purple
- non-resistant bacterium
Gram negative bacterium characteristics
- colours the bacterium blue
- thin peptidoglycan layer
- possesses an outer membrane
- ANTIBIOTIC RESISTANT.
The prokaryotic flagellum
-flagella made from many single fibres called flagellin
-hook and body responsible for movement in a liquid medium
Conjugation?
- occurs between a f(+) and an f (-) bacterium
- the f+ cell produces a F pillus or sex pillus (think of it growing a penis)
- and transfers the f plasmid through the conjugation bridge
- the f plasmid integrates into the f- now, f+ chromosome
Transduction: Generalised
General transduction happens with accidents during the lytic cycle, virus package dna and subsequent infection. Almost all genes can be transferred this way.
Transduction: specialised
Specialised transduction: involves accidents in the lysogenic cycle, its what the phage imprecisely excisions prophase dna, this can only transfer few genes
Transformation general
When a bacterial cell dies, it can burst open allowing its genes, dna and other material to exit the cell. This is picked up by the bacterium’s and is integrated into their genes.
