Marine Biology Notes Review

Marginal Seas

• shallower

• surrounded by land

• water chemistry different from open ocean

• EX: Caribbean, Mediterranean, North Sea, Gulf of Mexico

Sargasso Sea

• unique sea in middle of North Atlantic Ocean

• bound by surface currents

• known for accumulation of sargassum seaweed

Continental Shelf in Oceans

• low sloping platform from land extending to sea

• 10-300 km towards sea

• different between East/West coast

Continental Slope in Oceans

• depth of 200m

• steeper drop off

• connects sea floor to continental shelf

West Coast Continental Slope

narrow shelf, steep slope, inward prevailing winds

East Coast Continental Slope

broader shelf, gradual slope, outward prevailing winds

Deep Sea Floor

• 400 m deep

• has trenches and canyons

Ocean Ridges

• linear features rising 2000-4000 meters from floor

• seafloor mountain system formed by plates

• maintained by plate tectonics

• where seafloor spreading occurs

ocean floor is divided into

plates

east coast of US has been moved westward due to

• seafloor spread (spread in both directions from ridge)

• makes east coast a location of sediment formation

West Coast

• sits on a fault line

• more influenced by volcanic activity

• easier access to deep water

East Coast

• very gentle shelf

• more sandy

• takes longer to reach deep water from shore

covalent bond

• connects hydrogen with oxygen via shared electrons

• opposite charge gives molecule polarity

hydrogen bonds

• water molecules easily bond and break off from one another

specific heat

• takes a lot of energy to change temp of water

• ocean temps change with depth

thermocline

steep temperature gradient that separates warmer surface water from cooler water at depth

• low latitudes start warm

• high latitudes start cold

salinity

• aka saltiness of water

• measured in parts per thousand

• oceans average at 34/1000

oxygen in oceans

• normal range 4-6 mg/L

• air = 1200 mg/L

oxygen source

• where oxygen is getting added from or coming from

• wind moves and cycles water

• diffusion from atmosphere

• photosynthesis

oxygen sink

• where oxygen is disappearing or getting used by

• organisms and chemical reactions

stronger winds =

more oxygen dissolved and o2 gets deeper into water