Emphysema results when the delicate linings of the air sacs in the lungs become damaged beyond repair. Most commonly, the toxins in cigarette smoke create the damage. The lung changes of emphysema evolve slowly over years: 1  As the fragile tissues between air sacs are destroyed, air pockets in the lungs develop.2  Air becomes trapped in these spaces of damaged lung tissue.ost commonly, the toxins in cigarette smoke create the damage. The lung changes of emphysema evolve slowly over years: 1  As the fragile tissues between air sacs are destroyed, air pockets in the lungs develop. 2  Air becomes trapped in these spaces of damaged lung tissue.
In almost all toothed whale species, their teeth are cone-shaped and not used for chewing (the exception are Amazon River dolphins; they have two different types of teeth in their mouths). They hunt and catch one prey animal at a time, such as fish, squid, seals, sea lions and even birds.
The sperm whale is the largest toothed predator on earth. Several species exhibit sexual dimorphism, in that the females are larger than males. Baleen whales have no teeth; instead they have plates of baleen, a fringe-like structure used to expel water while retaining the krill and plankton which they feed on.