Emotion, motivation, olfaction, behavior, and memory, in humans, are mediated by the

Limbic system. Limbic system is a complex system of nerves and networks in the brain, involving several areas near the edge of the cortex concerned with instinct and mood. The limbic system supports a variety of functions including emotion, behavior, motivation, long-term memory, and olfaction. Emotional life is largely housed in the limbic system, and it has a great deal to do with the formation of memories.

answer; ///(b) it is composed of four protein chains and four heme groups;