Zusammenfassung der Ressource
Kingdom Monera
- All members of Monera are
prokaryotes
- Meaning they do not have a membrane-bound organells
- Structure of Bacteria
- Capsule is a dry layer and acts as an extra
layer of protection
- Cell wall protects and prevents the cell from
expanding and bursting
- Flagellum allows the cell to move or swim
- Cell membrane retains the cell contents and
controls what passes in and out of cell
- Plasmid is a small loop of DNA that contains genes
(which may cintrol antibiotic resistance)
- DNA contains genes that control the cell
- DOES NOT HAVE A NUCLEUS
- Types of Bacteria
- Spherical-shaped
- Spiral-shaped
- Rod-shaped
- Bacterial Reproduction
Anmerkungen:
- Bacterial reproduction is asexual
- Binary Fission
- The loop of DNA replicates
- The cell increases in size
- The two identical loops of DNA move to opposite ends of the cell
- Cell division occurs when the cell membrane and cell wall pinch in
- Endospore formation
- An endospore is a thick and tough-walled dormant and dehydrated
bacterial cell formed during unsuitable conditions
- Process of endospore formation
- Conditions become unfavourable for bacterium
- Cell undergoes asymmetrical binary fission (one cell is
larger than the other)
- The smaller cell is engulfed by larger cell
- A thick wall (cortex) forms around enflufed cell
- Outer coat forms around the cortex
- Nutrition in Bacteria
- Autotrophic nutrition is where the
bacteria produce their own food
- Chemosynthesis
- make food by converting one chemical into another
- Photosynthesis
- make food using light energy
- Heterotrophic nutrition is where bacteria
obtain their food and nutrients from other
living organisms
- Saprophytic
- live on and take in food from dead sources
- Parasitic
- take in food from a live host and usually
harms the host
- Food Processing
- Batch Processing
- Only a measured amount of nutrients are added
- Bacteria act on substrate and experiences lag,log and stationary phases
- Generally product is removed before decline phase
- Advantages
- It's a simple process
- It allows small volumes of products to form
- The micro-organisms grow naturally
- Bioreactor is sterilised and process starts again
- Product is separated from micro-organisms
- Continuous -flow Processing
- Nutrients are constantly added to the bioreactor at the
same rate at which the product is withdrawn
- Micro-organisms are kept at the log phase of growth
- Product is constantly removed from the bioreactor
- Advantages
- No time is wasted
- No need to sterilise bioreactor so often
- Product formed more rapidly
- Bioreactor is left open for inflow of nutrients and outflow of product
- Antibiotics
- are chemicals produced by
micro-organisms that kill or prevent the
growth of other micro-organisms
- No effect on viruses
- Overuse of Antibiotics
- Antibiotic Resistance
- When one bacterium develops a mutation that
enables it to avoid effects of an antibiotic
- This one resistant bacterium is then able to multiply