1) What are three ways that a symbiotic association can help its host defend itself?

2) What is the difference among predator, pathogen, and parasite?

3) Why do you think many endosymbionts have reduced genome sizes and cannot be cultured outside their insect hosts?

4) What is a ‘symbiosis island’?

5) What does it mean for genes to be ‘homologous’? ‘orthologous’? ‘paralogous’? ‘analogous’?