Tema 1 Flashcards
How does the density of seawater compare to air?
Seawater is 800 times denser than air.
How does seawater’s viscosity compare to air?
Seawater is 60 times more viscous than air, creating more resistance to movement.
What role does buoyancy play in seawater?
It provides support for structural materials, like algae and whales.
How does light behave differently in seawater compared to air?
Only blue light penetrates to great depths in seawater.
Compare sound transmission in seawater and air at 20°C.
Sound travels at 1518 m/s in water and 346 m/s in air.
How does electrical resistivity differ between seawater and air?
Seawater’s electrical resistivity is 10^16 times lower than air, enabling electroreception in some organisms.
How does pressure differ in seawater compared to air?
Pressure is significantly higher in seawater, affecting metabolism and organism distribution.
What is dissolved organic matter (DOM) like in seawater?
Seawater contains high levels of dissolved organic matter (DOM).
How does oxygen concentration in seawater compare to air?
Oxygen is lower and variable in seawater and can be insufficient in some areas.
What are photoautotrophs?
Organisms that use light energy to synthesize their own food.
What are the two main subdivisions of the sea?
Pelagic (open water) and Benthic (seafloor).
What are the horizontal divisions of the sea?
Neritic Zone: From low tide to the continental shelf edge (~200 m depth). Oceanic Zone: Beyond the continental shelf in open ocean.
What are the vertical divisions of the sea?
Epipelagic (0–200 m), Mesopelagic (200–1,000 m), Bathypelagic (1,000–4,000 m), Abyssopelagic (4,000–6,000 m), Hadopelagic (>6,000 m).
What are the two main types of plankton?
Phytoplankton (plant-like) and Zooplankton (animal-like).
What is holoplankton?
Organisms that spend their entire life cycle in the planktonic state.
What is meroplankton?
Organisms that are planktonic only for part of their life cycle.
What is the difference between pleuston and neuston?
Pleuston float at the water’s surface, while neuston live in or near the surface film.
What is nekton?
Actively swimming organisms in the pelagic zone.
What is the supralittoral zone?
The area above the high tide mark, rarely submerged.
What is the mesolittoral (intertidal) zone?
The area between tides, alternately submerged and exposed.
What is the sublittoral zone?
The area always submerged, below the low tide mark.
What are benthic organisms?
Organisms living on or near the seafloor.
What is the difference between epibenthos and endobenthos?
Epibenthos live on the seafloor surface, while endobenthos live within the sediment.
What is meiobenthos?
Very small benthic organisms.
