Topic 1

Question 1

What did Robert Hooke do?

Answer 1

Microscope pioneer
Draw fruit molds

Question 2

Who’s Antoni van Leeuwenhoek

Answer 2

Microscope builder
Father of microbiology
1st to see bacteria
Wee animalcules

Question 3

What is spontaneous generation?

Answer 3

Life con emerge spontaneously from non-living materials
E.G. dirty rags plus wheat plus 21 days = mice

Question 4

Who is Louis Pasteur?

Answer 4

In 1864, disproved spontaneous generation
Heat then seal = no growth →needs fresh air
Made swan neck to
Understand how fermentation works
Vaccine development
Pasteurization

Question 5

What is the germ theory of disease

Answer 5

Pasteur thought diseases are caused by microbes
Definitive evidence by Robert Koch
E.g anthrax found in dead cattle

Question 6

What are Koch’s postulates

Answer 6

Correlation has to exist
Isolate suspected pathogen
Put pathogen into healthy animal and cause disease
Reisolate pathogen and show it’s the same

Question 7

What are the implications/limitations of Koch’s postulates?

Answer 7

Cause & effect (Pathogen must cause the disease)
Scientific rigor, reproducibility
- some pathogens can’t be cultured or doesn’t always cause disease in healthy people but only in certain conditions

Question 8

What are microbes

Answer 8

Single celled organisms (mostly) from the three domains of life (bacteria, archaea and eukaryotes)

Question 9

What are viruses (not studied in this course)

Answer 9

Genetic elements (DNA,RNA) that can only multiply within a living cell by hijacking it to reproduced

Question 10

What is the RNA world hypothesis

Answer 10

Nucleotides (random non enzymatic polymerization) —> short oligomers (recombination) —> long oligomers

Question 11

What was the driving force for the creation of simple RNA nucleotides into long oligomers

Answer 11

Selection Pressures (stable, self-replicating, simple functions) i.e some RNA live longer, some replicate better therefore recombines better

Question 12

What is LUCA

Answer 12

Don’t exactly know what Last Universal Common Ancestor was
presumed features:
- DNA replication, transcription, translation, cell division
- ATP
- Lipid bilayer membrane
- Anaerobic (used H2 as energy source)

Question 13

The rise of oxygen on Earth

Answer 13

Phototrophs! - absobs light and transforms it into chemical energy
Chemotrophs: energy from releasing bond energies from chemical compounds

Question 14

Timeline of the rise of oxygen

Answer 14

first ~2 billion years Earth had no oxygen (anoxic)
- rise of cyanobacteria (oxygen as waste product)
- formation of ozone layer (protects against UV)

Question 15

Endosymbiotic Theory

Answer 15

Eukaryotes evovled from an Archaea-like ancestor that engulfed an aerobic respiring bacteria (alphaproteobacteria)
- became an endosymbiont (organism living inside another organisim)
- turned into mitochondria

Question 16

Endosymbiont for plants

Answer 16

engulfed photosynthetic bateria (cyanobacteria) which became the chloroplast

Question 17

2 theories of endosymbiosis

Answer 17

Serial Endosymbiosis vs Symbiogenesis

Question 18

What is the Serial endosymbiosis hypothesis

Answer 18

Complex cell structure evolves early, facilitating endosymbiosis

Question 19

What is the SYmbiogenesis hypothesis

Answer 19

Endosymbiosis occurs in an archaeal cell type, facilitating the evolution of cell complexity

Question 20

Evidence of Endosymbiotic theory

Answer 20

Mito and chloro
- have their own genomes
- bacterial machinery
- sequence comparisons; mito related to a-proteobacteria, chloro related to cyanobacteria

Question 21

How significant are microbes

Answer 21

around 1x10^30 while number of animals (mostly invertebrate) 2x10^19
make up a significant amount of biomass on earth

Question 22

How impactful are microbes to our lives

Answer 22

ubiquitous in daily living!
- animal health, human health, ecosystem health, water & waste, natural resources, agricultures, food, biotechnology, industry, bioenergy