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Adaptive Radiation

A process in evolution where organisms diversify rapidly into a wide variety of forms to adapt to different environments.

Mass Extinction

Extraordinary, sudden, and temporary changes in the environment that cause species to die on a huge scale.

Background Extinctions

Normal environmental changes, emerging diseases, predation, or competition that reduce populations to zero, differing from mass extinction.

What metric determines if there’s a mass extinction event?

If the actual rate of extinction is much greater than the background extinction rate, it may indicate a mass extinction event.

Bacteria

Prokaryotes with a peptidoglycan cell wall, simple transcription and translation processes, and found in various environments.

Archaea

Prokaryotes without peptidoglycan, possessing unique phospholipids, more complex transcription and translation processes, often found in extreme environments.

Heterotrophic

An organism that obtains its food from other organic substances, commonly seen in bacteria.

Extremophiles

Organisms, often archaea, that thrive in extreme environments such as hot springs and salt lakes.

Prokaryotes

Unicellular organisms with circular DNA that greatly outnumber eukaryotes and are found everywhere on Earth.

Virulence

The ability of an organism to cause disease, which is heritable and varies among individuals.

Endospore

Tough, thick-walled dormant structures formed by prokaryotes during environmental stress for protection.

Gram Positive Bacteria

Bacteria with a thicker peptidoglycan cell wall that turn purple/blue during gram staining.

Gram Negative Bacteria

Bacteria with a thinner peptidoglycan cell wall and an outer membrane that turn pink/red during gram staining, making them harder to treat with antibiotics.

Transformation

a cell dies and another cell sucks up the DNA left behind

Transduction

a virus transfers DNA from one cell to another

Conjugation

a tube transfers DNA from one cell to another