Answer: The correct answer is option 3) The amount of matter within the system remains the same and 5) The cycle has a well-defined starting and stopping point.
A closed system can be defined as a system in which there is the only exchange of energy with the surrounding, while no exchange of matter takes place.
In a closed system, the cycle has a well-defined starting and stopping point.
Therefore, the two generalizations which can be made for cycles of matter in a closed system are option 1) and 5)
Answer:
I'm pretty sure it's the white blood cells, because they contain antibodies to neutralise the pathogen :)
