Lec 03: Bacteria & Archea

What are bacteria and archea?

Prokaryotes.

Prokaryotes vs Eukaryotes?

• P - Lacks nucleus and membrane bound organelles.

• E - has these.

Archea vs bacteria what is the cell wall made up of?

• Pseudopeptidoglycan vs Peptidoglycan

Characteristics of prokaryotes.

• extremophiles (thriving in extreme conditions)

• ecosystem role = decomposition + nutrient cycling

Prokaryotic respiration.

Plasma membrane to house components of ETC.

Horizontal gene transfer:

• Transformation: uptake of DNA from the environment.

• Transduction: Transfers genes via viruses

• Conjugation: enables direct gene exchange under high density conditions.

What are the shapes of bacteria?

• Cocci - Spherical

• Bacili - Rods

• Spirilla - Spiral

How can prokaryotes move?

A flagella. (Gliding movement)

What are endospores?

• Formed by bacteria under harsh conditions.

• resistant to heat

What are biofilms? What is the point of it?

Communities of prokaryotes embedded in a slimy extracellular matrix.

• provide resistance to antibiotics.

• Common in dental plaque.

What are thermophiles?

Hydrothermal vents.

What are halophiles?

Salt loving.