Ch.12 - Marine Life & the Marine Environment

NASA’s definition of extraterrestrial life

self-sustained chemical system capable of evolution

Are marine species mostly benthic or pelagic?

benthic

Marine organisms adaptations for physical support

• buoyancy

• different support structures in cold vs warm seawater

• smaller size

Buoyancy adaptations

• high surface to volume ratio

• small

• unusual appendages inc surface area

• oil dec density → inc buoyancy

Is there more species in warmer or cooler seawater? More biomass?

species: warmer

biomass: cooler

Are floating organisms smaller in warmer of cooler seawater? More appendages?

smaller: warmer

more appendages: warmer

T/F Tropical organisms grow faster, have shorter lifespan, & reproduce more often

True

Do nutrients diffuse into or out of the cell? Waste?

Nutrients: into cell

Waste: Out of cell

What stops saltwater fish from dehydrating?

Chloride releasing cells in gills & releasing small volume of concentrated urine

How does water pressure inc?

inc about 1atm with every 10m deeper

Most important factor determining distribution of life in ocean province

sunlight

How is nutrient availability related to depth?

• nutrient avail inc with depth

• none in euphotic bc used up in photosynthesis