A tsunami is a natural disaster in which high speed waves generate in the ocean due to the gravitational force exerted by the moon on the water of the ocean resulting in flood. But these may also occur because of the underwater earthquakes, landslides and volcanic eruptions. All these events causes changes in the sea floor.
Therefore, tsunami will occur when an earthquake causes a sudden vertical change in the sea floor.
<span>The role of a restriction enzyme is essentially used to cut a single gene from a larger piece of DNA. It has a very important role to play in experiments investigating cloning, and in the construction of particular DNA molecules.</span>
A<em> fish ladder</em> is also known as fish steps, fish pass or fishway.
It is built around waterfalls, dams and locks.
The purpose of building a fish ladder is to<em> facilitate the natural migration of diadromous fishes.</em>
A fish ladder helps the fish to pass through the barriers by leaping up or swimming through the low steps of the ladder and reach into the water on the other side.
Since, without the fish ladder the barriers will not allow the migration of fishes, it is essential to be built around the dams, waterfalls and locks.
