Words and concepts

Question 1

continental shelf

Answer 1

water deepens near coast

Question 2

continental slope

Answer 2

after shelf gradient increases

Question 3

continental rise

Answer 3

wide gently sloping after slope

Question 4

abyssal plain

Answer 4

deepest area

Question 5

guyots

Answer 5

peaks in abyssal plain that used to rise above ocean but were eroded and top flattened

Question 6

rift valley

Answer 6

valley formed by downfaulting between parallel faults

Question 7

subduction zone

Answer 7

where oceanic plate descends into Earth’s mantle and is destroyed

Question 8

oceanic trench

Answer 8

narrow, deep depression on ocean floor adjacent to subduction zone

Question 9

salinity

Answer 9

measure of concentration of salt in water, parts per thousand grams of water

Question 10

freshwater salinity

Answer 10

<0.5ppt

Question 11

average ocean salinity

Answer 11

30-35ppt

Question 12

variations in salinity

Answer 12

higher with more depth, affects density, density difference creates currents

Question 13

surface currents

Answer 13

surface circulation, 10% of ocean water, upper 400m of ocean

Question 14

deep water currents

Answer 14

thermohaline circulation, 90% of ocean, move around ocean basins with density and gravity

Question 15

ocean current influenced by

Answer 15

solar heating, winds, gravity, Coriolis effect

Question 16

ocean conveyor belt

Answer 16

continuous slow flow of currents around globe

Question 17

sequence of currents

Answer 17

warm surface water and cold deeper, surface water moves upwards in latitude, polar surface currents are colder and more saline so denser, waver sinks and moves horizontally, deep currents flow back to equator and rise

Question 18

light affecting ecosystems

Answer 18

more photosynthesis in higher levels called photic zone, greater surface area covered farther from equator due to angle

Question 19

temperature affecting ecosystems

Answer 19

related to sunlight, more depth, less temp

Question 20

nutrient supply affecting ecosystems

Answer 20

dissolved nutrients (nitrogen, iron and zinc) from rocks carried from rivers to ocean, plankton hold them and pass food chain, nutrients returned to water as waste, deeper denser water holds nutrients near floor, except in Antarctica where strong upward movement has nutrients nearer surface

Question 21

producers

Answer 21

organism captures energy from Sun with photosynthesis and stores energy as organic matter

Question 22

Net Primary Productivity (NPP)

Answer 22

energy produced by plants, taking into accoyunt energy used for respiration

Question 23

salt marsh

Answer 23

vegetated mudflat or coastal wetland, affected by tidal rise and fall