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.

Fact 1: Many nerve pathways link the cerebellum with motor neurons throughout the body. 
Fact 2: And the human body is no exception.
In a human, the nerve pathways link the cerebellum with motor neurons.

Fact 1: crossing two living things with recessive traits causes their offspring to have that recessive trait. 
Fact 2: Mutations cause various differences between the offspring and their parents.
recessive traits causes Mutations.

Fact 1: when a plant grows , the size of the leaves of that plant may increase. 
Fact 2: Leaves help carry on photosynthesis.

as a plant grows, photosynthesis increases.