Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

[Q]: Question: What are animal fats and oils such as olive and vegetable oil classified as? Answer: lipids
[A]: A: Lipids that are fats include butter and the fats in meats. Lipids that are oils include olive oil and vegetable oil. Examples of both types of lipids are pictured in the Figure below .

[Q]: Question: What is the outer core made of? Answer: liquid metal
[A]: Yes! The outer core, anyway. The outer core is liquid metal, like in this photo. Of course, the metal is under an incredible amount of pressure.

[Q]: Question: In a model of a hemoglobin molecule, the purple part indicates the presence of what element? Answer: iron
[A]:
Hemoglobin Molecule. This model represents the protein hemoglobin. The purple part of the molecule contains iron. The iron binds with oxygen molecules.