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: Cartilage is a tough tissue that contains a protein called collagen. 
Fact 2: Membranes attached to the cricoid cartilage .

A: Cricoid is a tough tissue that contains a protein called collagen.
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Q: Fact 1: Mammals conserve body heat with their hair or fur. 
Fact 2: Hair and feathers are both made of keratin.

A: mammals conserve body heat with keratin.
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Q: Fact 1: heating an egg causes a chemical reaction in the egg. 
Fact 2: Chemical changes are a result of chemical reactions.

A:
Heating an egg results in chemical changes.
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