Answer:
The first line of defense involves skin.
Answer:
all of the above can lead to increase in nitrogen
Sea otters are a keystone species. They play an important role in the health and stability of near shore marine ecosystems. They eat sea urchins and other invertebrates that eat vast quantities of giant kelp. ... Providing habitat is one of many services kelp offers to the marine ecosystem.
The blubber fat layer and white fur helps the polar bears to maintain internal homeostasis in cold weather.
