Bio 1.6 : Microbes

What are microbes?

Also known as microorganisms, microbes are important for the environment, ecosystems and humans.

What are some of the common microbes?

Common microbes include bacteria, fungi, viruses and protists. Can also include multicellular parasites.

What are fungi?

• Both uni and multicellular

• Eukaryotic

• 2-10 micrometres in size.

• Heterotrophs

Fungi examples

yeast or mould

What are protists?

• Unicellular but can be multicellular

• Eukaryotic

• 1 micrometre in size

• Autotrophs and heterotrophs

Protists examples

Plasmodium protoza (cause of malaria)

What are viruses?

• Not actually living as it doesn’t follow MRS GREN

• however they act very similar to microorganisms

  • 20-400 nanometres in size

Virus examples

Influenza or norovirus

What is bacteria?

• Unicellular

• Prokaryotes

• 0.2 - 10 micrometres in size

  • Divided via binary fission

Bacteria examples

E-coli or bacillus anthracis

Microbes in the digestive system

• Bacteria is present in the large intestine and referred to as gut microbiomes

• That bacteria has enzymes that break down sugars that the human body cannot digest.

  • The other bacteria present synthesises the enzymes and vitamin K for the body to utilise.

Microbes in the enviroment

• Ocean ecosystems are dependent on phytoplankton

• Phytoplankton are autotrophs and form the basics of oceanic food chain

  • Their production of oxygen is used by other organisms in the ocean.

microbes as decomposers

• Microbes recycle nutrients in ecosystems.

• Bacteria and fungi break down detritus which is a non-living organic waste.

  • This can then be converted into inorganic compounds such as carbon dioxide.

Microbes in food preservation

• Microbes have enzymes that break down food through different processes such as rotting.

• Microbes are the primary cause of foodborne diseases.

  • food preservation techniques eliminate or reduce the population of microbes.

Food preservation techniques

• reducing temperature

• Increasing temperature

• removal of water

• chemical preservation

• radiation