L39 Microbial growth and behaviour (Winogradsky column)

Question 1 of 12

1

Choose the incorrect statement about trophic nourishment.

Select one of the following:

Chemoheterotrophs can get their energy and carbon from the same organic compound.
A phototroph uses light as en energy source, and can be oxygenic or anoxygenic.
A chemotroph uses chemical energy as an energy source.
Autotrophs can make complex carbons from CO2.
Anoxygenic phototrophs oxidise molecules like H2S and do not produce oxygen.
Oxygenic phototrophs reduce H2O and produce oxygen.

Explanation

Question 2 of 12

1

Choose the correct statements about cyanobacteria.

Select one or more of the following:

They use light as an energy source.
They oxidise water for electrons.
They use complex carbons for a carbon source.
They carry out oxygenic photosynthesis.
They reduce water for electrons.

Explanation

Question 3 of 12

1

Choose the incorrect statement about green and purple cyanobacteria.

Select one of the following:

They are photoautotrophs.
They oxidise H2S to S for an electron source.
They use CO2 for an energy source.

Explanation

Question 4 of 12

1

Choose the correct statement about colourless sulfur bacteria(Beggiatoa).

Select one of the following:

They sit below green and purple sulfur bacteria in the Winogradsky column.
They are chemoheterotrophs.
They oxidise H2S to SO4.
They use complex organic carbons for a carbon source.

Explanation

Question 5 of 12

1

Sulfate reducing bacteria are chemoheterotrophs that essentially reverse the processes that colourless sulfur bacteria carry out.

Select one of the following:

True
False

Explanation

Question 6 of 12

1

Organisms which carry out fermentation are ❌. Their energy source, carbon source, and electron donor, are always ❌ (organic molecules) and sometimes are even the same molecule. An example of ❌ are cellulose degrading bacteria, which break pyruvate down into ❌ and simultaneously degrade cellulose into ❌. Other examples include clostridium and ❌ bacteria.

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chemoheterotrophs

chemoautotrophs

complex carbons

fermenting chemoheterotrophs

fermenting chemoautotrophs

acetate

acetic acid

lactate

lactose

rumen

colourless sulfur

Explanation

Question 7 of 12

1

Microbial growth in a ❌ culture system is not like nature, in that it is a 'Feast and ❌' situation controlled by the examiner. There are four stages which characterise the growth ❌ for bacteria in this system.
Firstly, there is a ❌. It is shown as little to no change in the population size. The lag period ❌ on how much the inoculum must evolve and adjust before it is suited to the environment/has the proper ❌ taking place.
The next phase is the ❌. During this phase there are ❌ or competition and so the bacterial population can ❌ in size every generation via binary fission, displaying exponential population growth.
The next phase is the ❌. This appears to be a stable population size, but does not indicate static activity. Instead, it reflects the cryptic growth of the organisms. Cryptic growth is the state of ❌ equilibrium where organisms survive by feeding from the lysed, dead bodies of deceased organisms.
Finally, there will be a ❌ where the population size decreases until it is at a stable end point.

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closed batch

open batch

Famine

curve

lag phase

exponential phase

stationary phase

death phase

depends

biosynthetic reactions

double

no limited resources

limited resources

dynamic

Explanation

Question 8 of 12

1

What might cause a persistent bacterial infection?

Select one of the following:

Microbes which are able to degrade antibiotics.
Microbes not all being in the same stage of a life cycle, and the non-dividing organisms not being targeted by antibiotics.
Microbes which can repopulate faster than a patient can be medicated.

Explanation

Question 9 of 12

1

To be antibiotic resistant a microbe must carry the genes which confer resistance.

Select one of the following:

True
False

Explanation

Question 10 of 12

1

Choose the incorrect statement about microbial behaviour.

Select one of the following:

Some bacteria are very large e.g. thiomargarita.
Some bacteria have organelles e.g. Anammox bacteria
Myxobacteria display social behaviour.
None of these are incorrect.

Explanation

Question 11 of 12

1

Which statement best describe the 'sliding' behaviour displayed by myxobacteria.

Select one of the following:

It is a form of social motility wherein each bacteria pulls with pili and secretes slime like a propellent.
It is the microbial version of hunting like a wolf pack.
It is swarm feeding cooperatively by sharing enzymes and attacking targets as a group.

Explanation

Question 12 of 12

1

When a food source is exhausted, myxobacteria form 3D structures of endospores. What are these referred to as?

Select one of the following:

Fruiting bodies
Sporing bodies
Endospikes

	Created by Mer Scott almost 7 years ago

1.Describe the different energy and carbon sources used by microorganisms. 2.Describe the growth characteristics of prokaryotes in a ‘closed’ batch culture system. 3.Outline some examples of microbial behaviour.

L39 Microbial growth and behaviour (Winogradsky column)

Question 1 of 12

Choose the incorrect statement about trophic nourishment.

Select one of the following:

Explanation

Question 2 of 12

Choose the correct statements about cyanobacteria.

Select one or more of the following:

Explanation

Question 3 of 12

Choose the incorrect statement about green and purple cyanobacteria.

Select one of the following:

Explanation

Question 4 of 12

Choose the correct statement about colourless sulfur bacteria(Beggiatoa).

Select one of the following:

Explanation

Question 5 of 12

Sulfate reducing bacteria are chemoheterotrophs that essentially reverse the processes that colourless sulfur bacteria carry out.

Select one of the following:

Explanation

Question 6 of 12

Drag and drop to complete the text.

Explanation

Question 7 of 12

Drag and drop to complete the text.

Explanation

Question 8 of 12

What might cause a persistent bacterial infection?

Select one of the following:

Explanation

Question 9 of 12

To be antibiotic resistant a microbe must carry the genes which confer resistance.

Select one of the following:

Explanation

Question 10 of 12

Choose the incorrect statement about microbial behaviour.

Select one of the following:

Explanation

Question 11 of 12

Which statement best describe the 'sliding' behaviour displayed by myxobacteria.

Select one of the following:

Explanation

Question 12 of 12

When a food source is exhausted, myxobacteria form 3D structures of endospores. What are these referred to as?

Select one of the following:

Explanation