Fragmentation never occur in a unicellular organism !!
Sterilization is the process that kills all microbes by the use of physical/chemical agents.
Answer:
The brackish water adaptation is clearly necessary because the aquatic snails need to live in an environment in which the river system has a higher quantity of salt than what land snails can take. I can determine that the environmental factors influenced the inherited adaptations because the second population has a higher salt concentration in their habitat compared to the initial population.
Answer:
They repel one another. I think