5. how do tiny biogenous tests, that would otherwise be carried horizontally long distances by currents, reach the ocean floor directly below where test secreting organisms live? they sink vertically in fecal pellets excreted by heterotrophic organisms. b. adsorption to vertically sinking precipitates. they are swept vertically into turbidity currents. d. they percolate vertically through hydrothermal vents

a mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. this uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.a geomagnetic reversal is a change in a planet's magnetic field such that the positions of magnetic north and magnetic south are interchanged.

answer (a) more rain in u s and less rain in australia and asia