Topic 9 - Prokaryote

Question 1

Structure of Archaea and Bacteria, and their differences

Answer 1

Bacteria
- Flagella
- Fimbrae
- Capsule
- Cell wall (peptidoglycan)
- Plasma membrane
- Circular bacteria chromosome
- Simple organelles

Archaea
- Flagella
- Fimbrae
- Capsule
- Cell wall (pseudopeptidoglycan)
- Plasma membrane
- Circular prokaryote chromosome
- Histones
- More complex organelles yet still simple

Question 2

How do cellular mechanisms in bacteria influence population dynamics and evolution?

Answer 2

• Asexual reproduction by binary fission produces one double the amount of offsprings
• Rapid evolution through rapid division

Question 3

Differentiate between gram positive and gram negative

Answer 3

Positive
- Water soluble membranes
- More susceptible to antibiotics
- Cell wall made solely out of peptidoglycan

Negative
- Non water soluble membranes
- Less susceptible to antibiotics
- Cell wall has outer membrane and layer of peptidoglycan

Question 4

What are mechanisms that can lead to antibiotic resistance?

Answer 4

• genetic variation between bacterial strains
• heritability
• selection for resistance

Question 5

Importance of bacteria

Answer 5

• Essential in the gut for processing food
• Abundant in the microbiome through commensalism (beneficial for one party, other is not helped or harmed)
• Essential in producing certain foods and medicines

Question 6

Importance of prokaryotes

Answer 6

• Absorb energy from outside ecosystem and distribute nutrients back
• Assimilating materials into biomass passed into upper trophic levels (decomposers)

Question 7

Horizontal vs. Vertical gene transer

Answer 7

DRAW IT OR PICTURE IT

Question 8

Three processes that can lead to formation of recombinant bacteria

Answer 8

Conjugation
- Cells join through pilus, establishes mating bridge, plasmid is transferred
- F-factor gene required to make pilus
- R-plasmid confer antibiotic resistance

Transduction
- Exchange of DNA through virus called bacteriophage

Transformation
- Release of DNA which gets taken up by another bacteria