Microbial Symbioses Lecture Notes

These flashcards cover key concepts from the lecture notes on microbial symbioses, including definitions, roles of organisms, and specific examples of symbiotic relationships in various ecosystems.

What is a mutualism in microbial symbioses?

Interactions where both organisms benefit from the relationship.

What are lichens composed of?

A mutualistic relationship between a fungus and an alga or cyanobacterium.

What do nitrogen-fixing bacteria in legumes do?

They fix nitrogen, making it available to the plant.

What is the main role of leghemoglobin in root nodules?

To bind free oxygen so that it does not inactivate nitrogenases during nitrogen fixation.

How do ectomycorrhizae differ from endomycorrhizae?

Ectomycorrhizae remain outside the plant roots, while endomycorrhizae embed deeply within root tissues.

What is the role of the Ti plasmid in Agrobacterium tumefaciens?

It induces tumor formation in plants and is used in genetic engineering.

What do heritable symbionts in insects require?

They are obligate and essential for the host's reproduction.

How do leafcutter ants use their symbiotic relationship with fungi?

They cultivate fungi using leaf fragments to feed them, forming a mutualistic association.

What is coral bleaching caused by?

The loss of color due to lysis of symbionts when exposed to high temperature and light.

How do rumen microbes contribute to their host's nutrition?

They synthesize amino acids and vitamins for the host and serve as a protein source when digested.