Micro-organisms Flashcards
Characteristics of bacteria?
-Small
-Found everywhere
-Kingdom Monera
-Uni-cellular
-No nucleus
-Heterotrophs or autotrophs
What is a heterotroph?
Cannot make their own food but take in food from other organisms
What is an autotroph?
Make their own food
Bacteria shapes?
-Round, e.g. tetanus
-Rod, e.g. streptococcus
-Spiral, e.g. syphilis
Explain how bacteria reproduces?
Called binary fission
-DNA replicates
-Cell elongates causing DNA to divide
-Cells separate
Optimum conditions for bacteria division?
- Temperature (colder=slower growth)
- pH (7)
- Access to oxygen
Pros of bacteria? (economic uses)
-Makes yoghurts and cheese
-Makes antibiotics
Cons of bacteria?
-Causes food to go bad
-Can cause diseases (pathogens)
Uses for antibiotics?
-Transplants
-Dialysis
-Suppressed immune systems
-Joint replacements
What is antibiotic resistance?
As bacteria reproduce so quickly, mutations are more likely to occur. This causes the bacteria to no longer be killed by antibiotics
Characteristics of viruses?
-Smallest micro-organism type
-Parasite
-Can often damage and kill host cells
-E.g. Covid 19, influenza, chicken pox
Explain the structure of a virus
Nucleic acid (DNA or RNA) is protected by a protein coat
Non-living features of a virus?
-Contains DNA or RNA, not both (living things contain both)
-Cannot reproduce by themselves
Living features of a virus?
-Have a protein coat
-Contain DNA or RNA
Explain viral reproduction
-Viruses are obligate parasites, meaning they need a host to reproduce and survive
What is bacteriophage?
A virus that infects bacteria to replicate
What are the stages of replication?
- Attachment
- Entry
- Synthesis
- Assembly
- Release
Annie Eats Super Airy Rice
Explain attachment in viral replication
Virus attaches to host
Explain entry in viral replication
Viruses make a hole in the cell wall and inject nucleic acid
Explain synthesis in viral replication
Host DNA is made inactive and the viral DNA uses bacterial organelles to produce new viral nucleic acid and proteins
Explain assembly in viral replication
New viruses are made inside the infectional cell
Explain release in viral replication
Bursting of cell occurs, releasing thousands of viruses
Examples of viral human diseases
-Common cold
-AIDS
-Mumps
Examples of viral plant diseases
-Potato mosaic disease
-Tobacco mosaic disease
Examples of viral animal diseases
-Foot and mouth
-Rabies
