Ocean Currents

We talk about ocean currents in class. Now to improve your knowledge about them watch the following video and answer the questions:

1) What factors influence the origin of the currents?
2) What are the direction of the currents in the Northern Hemiphere? And in the Southern one?
3) How are currents originated in the polar regions? What currents are they?
4) How are currents originated in the equatorial regions? What currents are they?