What characterizes the lipids commonly referred to as oils?

Oils are primarily characterized by a high degree of unsaturated bonds in their fatty acid chains. Unsaturated fatty acids contain one or more double bonds between carbon atoms, which can lead to a more liquid state at room temperature. This is because the presence of double bonds creates kinks in the fatty acid chains, preventing them from packing closely together, thus resulting in a lower melting point and a fluid consistency.

In contrast, saturated fats have no double bonds and are typically solid at room temperature due to their straight structure, allowing them to pack tightly. Therefore, oils are distinguished from solid fats by their higher levels of unsaturation, making the presence of a high degree of unsaturated bonds a key characteristic of oils in the context of lipids.