Question

The Southern Oscillation can be best described as

	relative changes between two pressure systems.
	variation in wind speed over the Pacific Ocean.
	relationship between sea-surface and high-altitude pressures.
	tidal differences between the Indian and Pacific Oceans.
	wind-speed differences along the Equator.

The long spines and projections seen in many epipelagic plankton are used for

	feeding.
	reproduction.
	increasing drag.
	increasing buoyancy.
	gathering nutrients.

Answer 1

1. Southern oscillation is the tidal differences between the Indian and Pacific Oceans.

2. The long spines and projections seen in many epipelagic plankton are used for increasing drag.

mostly epipelagic fish have a tail that is high and narrow which increases their movement.