Symbiosis Considerations (Section 1)

1 Relative Positions of Partners 

Ectosybmioses (external)

Episybioses (on top) 

Inside = Endosymbionts 

• Extracellular ( In the cellular tissue but between cells) 

• Intracelullar ( A larger organism letting one into its cells)

Bacteriocyte = The cell that holds the bacteria and can be regulated within it

Symbiosome is the cell that individualy swallows a single microbe 

2 Specific Mode of Interaction 

• Nutritional 

  • Carbon (algae)

  • Nitrogen (termites)

  • Amino acids (affids) 

  • Vitamins (blood feeders) 

• Defensive (biotic and abiotic) 

  • Antipredation

  • Antifowling 

  • Antiherbivory

  • Drought tolerance 

  • Thermal tolerance 

Other 

 Killer Symbiosis = Nematodes 

• Developmental (ants and their 5th final molt) 

• Many still unknown 

3 General Effects on Fitness (Reproduction) 

Reproduction 

Survival 

Growth