instruction:
You are given a sentence and your task is to generate another sentence that supports the given input.
question:
The significance of these changes lies in the demonstration that they were associated with the release of calcium ion, which as a 'second messenger', was proposed in turn to activate systems that direct development of the early stages of the parasite (94).
answer:
Calcium ion is an example of a second messenger.

question:
3.14) Ocean Tides and the Moon There are two high and two low tides daily.
answer:
Two low and high tides occur per day.

question:
Carbon dioxide, an important greenhouse gas, dissolves in rainwater to form carbonic acid which weathers silicate rock to form carbonates oa particularly common form being limestone.
answer:
Carbon dioxide chemically weather rocks by creating acids.