Diversity of Bacteria and Archaea

What are the three main principles of Cell Theory?

1. Cells are the basic unit of life. 2. All life is made of cells. 3. Cells arise from other cells.

What type of cells are prokaryotic?

Prokaryotic cells are cells that lack a nucleus and are generally smaller; they include Bacteria and Archaea.

What are the key differences between Bacteria and Archaea?

Both lack a nuclear membrane and have circular chromosomes, but Archaea have histone proteins while Bacteria do not.

What distinguishes Eukarya from Bacteria and Archaea?

Eukarya have a nuclear membrane, linear chromosomes, and complex RNA polymerase.

What is MRSA?

Methicillin-resistant Staphylococcus aureus, an antibiotic-resistant bacterium that can cause severe infections.

What role does the gut microbiome play in human health?

The gut microbiome consists of beneficial bacteria that are important for digestion, immunity, and overall health.

Name one example of an extremophile and its habitat.

Halophiles, which live in high-salt environments.

What are the three types of Lateral Gene Transfer (LGT)?

1. Transformation: Uptake of DNA from the environment. 2. Transduction: Transfer via viruses. 3. Conjugation: Direct transfer between bacteria.

What is the Morphological Species Concept?

A classification method based on the structure of organisms, often using culturing methods.

What is the Phylogenetic Species Concept?

A classification method based on genetic sequencing, providing a more accurate classification.

Why is the classification of prokaryotic species challenging?

Many bacteria cannot be cultured, and horizontal gene transfer complicates classification.

What are some roles of bacteria in the environment?

Bacteria can be pathogens (harmful), beneficial symbionts (helpful), or extremophiles (able to thrive in extreme conditions).