Combine the given two facts to write a concluding fact. Note that there should be some parts of the first and second facts that are not mentioned in this conclusion fact. Your combined fact should be the result of a chain between the two facts. Chains form when two facts connect together to produce a concluding fact. An example of a chain is: "pesticides cause pollution" (fact1) + "pollution can harm animals" (fact2) → "pesticides can harm animals" (conclusion fact). Parts of the concluding fact overlap with the first and the second fact. To construct such a  concluding fact, a useful way is to borrow the subject from one fact and the ending conclusions from another fact.

[Q]: Fact 1: Mollusks reproduce sexually. 
Fact 2: Some mollusks have a shell.
[A]: some animals with shells reproduce sexually.


[Q]: Fact 1: planting trees has a positive impact on an ecosystem. 
Fact 2: Biodiversity encourages a healthier ecosystem.
[A]: planting trees has a positive impact on biodiversity.


[Q]: Fact 1: Sperm had to swim from male to female reproductive organs for fertilization. 
Fact 2: Fertilization is the penetration of the egg by a sperm.
[A]:
Sperm must swim from the male to the female egg.