Foam cells are a type of macrophage that localize to fatty deposits on blood vessel walls, where they ingest low-density lipoproteins and become laden with lipids, giving them a foamy appearance.

We'll test your senses about how animals see, hear and smell. Find out which animal uses it's eyes to swallow, which has ears on it's knees and which has a sense of smell 100,000 stronger than a human ...