AP-Micro Microbiology: Microbial Ecology and Pathogenesis 2

Question 1

Which term describes the relationship where one organism benefits and the other is neither helped nor harmed?

Accepted Answer

Commensalism

Answer

Mutualism

Answer

Parasitism

Answer

Amensalism

Question 2

A bacterium that can only cause disease when the host's immune system is compromised is classified as a:

Accepted Answer

Opportunistic pathogen

Answer

Primary pathogen

Answer

Commensal organism

Answer

Saprophyte

Question 3

The term 'Koch's postulates' refers to criteria used to:

Accepted Answer

Establish causation between a microbe and a disease

Answer

Classify bacteria by Gram stain

Answer

Measure bacterial growth rate

Answer

Determine antibiotic resistance

Question 4

Which of the following best describes a biofilm?

Accepted Answer

A structured community of microbes encased in a self-produced matrix

Answer

A single-layer suspension of bacteria in liquid

Answer

A thin film of nutrients on laboratory media

Answer

A viral protein coat surrounding host cells

Question 5

Nitrogen fixation in ecosystems is primarily performed by:

Accepted Answer

Certain bacteria and archaea

Answer

Fungi and protozoa

Answer

Algae and diatoms

Answer

Viruses integrated into plant DNA

Question 6

Exotoxins differ from endotoxins primarily because exotoxins are:

Accepted Answer

Secreted proteins produced by living bacteria

Answer

Part of the outer membrane of Gram-negative bacteria

Answer

Always heat-stable lipopolysaccharides

Answer

Released only upon bacterial death

Question 7

Which ecological concept describes the role a microorganism plays in its environment, including its resource use and interactions?

Accepted Answer

Niche

Answer

Habitat

Answer

Biome

Answer

Ecotone