What is the difference between conserving energy and the law of conservation of energy

What element is able to combine with itself and hydrogen to form large molecules ?

Explain how sequences of amino acids in proteins can be used to reveal relationships among organisms.

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?