Lysozyme which is found in the lysosomes. They function at a relatively low pH and are so because if they functioned at physiological pH they would digest the cell. But in this case, they are in the lysosomes where they are safe and at a lower pH so when the vesicles open they can emit hydrogen ions and the lysozyme to digest the foreign material.
If a zebra mussel is discovered in a lake in Pennsylvania, then the ecologist would be worried because it is an invasive species. The zebra mussel is native to Ukraine and Russia, but if it has been found in Pennsylvania, than it means that it has been introduced in this area. As an invasive species, the zebra mussel can be very dangerous for the native species in the lake. The invasive species usually are more competitive for food sources than the native species, manage to reproduce quicker, bring in diseases, and the native species tend to not have defense mechanisms for them. This leads to rapid decline or even extinction in the native species, while the invasive spreads out quickly and takes over, resulting in dramatic change in the whole ecosystem.
<span>284 km in 2 million years.</span>
