Microbiology Introduction (MICROBIO Unit 1)

What is microbiology

It is the study of microorganisms too small to be seen by the naked eye.

Importance of studying microorganisms (3)

Critical for recycling essential elements
Producing nutrients
Contributing to industrial processes

What are the importance of microorganisms (5)

Oldest form of life
Largest mass of living material on earth
Carry out major processes for biogeochemical cycles
Can live in places unsuitable for other organisms
Other life forms require microbes to survive

Define “The Cell”

A dynamic entity that forms the fundamental unit of life

What are the characteristics of living systems (6)

Metabolism
Reproduction
Differentiation
Communication
Movement
Evolution

True or false cells can be used as catalyst, why

True, through the use of enzymes or the cell’s protein catalyst

True or false, cells can be used as a coding device, why

True, cells can store and process information via deoxyribonucleic acid (DNA)

What is microbial community

Microbes in nature in populations of interacting assemblages

What is habitat

The environment in which a microbial population lives

What is ecosystem

Refers to all living organisms plus the physical and chemical constituents of its environment

What is microbial ecology

It is the study of microbes in their natural environment

What factors determines abundance and diversity of microbes? (2)

Resources (nutrients)
Environmental conditions (temp, pH, O₂)

True or false, microbial communities can affect chemical and physical properties of habitats

True

What is LUCA

Last Unknown Common Ancestor

How old is the Earth

4.6 billion years old

Robert Hooke

First to describe microbes

Anton Van Leewuenhoek

First to describe bacteria

Ferdinand Cohn

Founded the field of bacterial classification and discovered bacterial endospores

Who is Louis Pasteur (5)

Discovered that organisms discriminate between optical isomers
Discovered that fermentation is a biologically mediated process
Disproved theory of spontaneous generation
His work led to the development of aseptic technique
Developed vaccines for anthrax, cholera and rabies

Pasteur Swan-neck experiment

1) Prepared nutrient broth in flask
2) Curved the flask neck
3) Sterilized the broth through heating
4) Broth cooled slowly
5) Flask tipped to touch the microbe-filled neck
6) Liquid putrefies (rot)

What is significance of swan neck experiment (3)

Disproved spontaneous generation (Abiogenesis)
Laid the foundation for germ-theory for disease
Pioneered sterilization and aseptic techniques

Who is Robert Koch (3)

Developed Koch Postulates
Developed techniques for obtaining microbial pure culture
Demonstrated link between microbes and diseases

What are Koch postulates (4)

1) Suspected pathogen must be present in all cases of the diseased and absent from healthy animals
2) Suspected pathogen must be grown in pure culture
3) Cells from pure culture of the suspected pathogen must cause disease in a healthy animal
4) Suspected pathogen must be reisolated and show similarity with original

Limitations of Koch’s Postulates

Postulates only apply for pathogens with appropriate animal models
Postulates cannot be applied when animal model is not possible
Not all diseases satisfy all postulates

Who is Martinus Beijenerick

Developed culture enrichment techniques

Who is Sergei Winogradsky

Discovered chemolithotroph