Summary
Summary Microbiology Gr11
- Course
- Life Sciences
- Institution
- 11
A summary of the microbiology section of Grade 11 Life Science.
[Show more]
Seller
Follow
Content preview
Microbiology and immune systemViruses, bacteria, protists, and fungi
V, B, P, F are all:
Hugely diverse group found in all environments.
Occur in vast numbers
Vary in size:
1. Invisible to naked eye – micro-organisms (microbes)
2. Visible – macro-organisms
Acellular (V) or cellular (B, P, F)
Prokaryotes – B
Eukaryotes – F, P
Unicellular or form colonies
Pathogenic and non-pathogenic
Pathogenic – disease causing
Non-pathogenic – harmless
Disease causing = pathogens = germs
Viruses
Infect animals, plants, even bacteria.
Characteristics:
Extremely small – microscopic
Exist in 2 states
1. Virus – when active
2. Virion – when dormant (not in contact with host)
Not living organisms
Only survive inside host cells
Only reproduce inside a living cell
Always associated with disease
Can remain dormant within an organism
Different shapes:
1. Polyhedral – cuboidal
2. Helical – spiral
3. Complex – tadpole
Structure:
Acellular – not a cell
Core of DNA or RNA
Hereditary information not enclosed in a nuclear membrane.
Nucleic acid surrounded by protein coat or capsid.
Some viruses, capsid is covered by an envelope of a lipid bilayer. Used to protect the virus from
host’s nuclease enzyme.
Bacteria
, Unicellular micro-organisms
Group - Monera
General characteristics:
Most diverse and abundant group.
Inhabit all env.
Extremophiles: thrive in climatic or environmental extremes. (Intense heat or cold)
Mostly useful.
Unicellular among the smallest organisms.
Vary in shape:
1. Cocci – spherical bacteria
2. Bacilli – rod-shaped bacteria
3. Spiralla – spiral shaped
4. Vibrios – comma-shaped
Exist singly, in chains or in clumps.
In favorable conditions bacteria reproduce by binary fission.
In unfavorable conditions bacteria can survive dormant.
Structure:
Unicellular
Rigid cell wall
Plasma membrane is a multipurpose structure:
- Serves as mitochondrion, endoplasmic reticulum and sometimes even chloroplast.
- Also controls entry and exit of materials.
Procaryotes
- No nuclear membrane
- DNA does not combine with histone, protein as in eukaryotic cells.
Closed loop of bacteria.
Waxy capsule as outermost layer.
Flagella, enable them to move.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller madisonash2004. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R153,00. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67866 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy summaries for 14 years now