Chapter 13: The Marine Habitat

Most organisms live in euphotic zone Sunlight Nutrients Marine algae

Other organisms need algae Directly or indirectly

Classification

Three domains Archaea Bacteria Eukarya

Classification

Four Kingdoms Protista Fungi Plantae Animalia

Fig. 13-1

Taxonomy Kingdom Phylum Class Order Family Genus Species

Fig. 13-4

Classification of marine life By life style

Plankton floaters Phytoplankton Zooplankton Baterioplankton

Plankton make up most of Earth’s biomass

Phytoplankton

Fig. 13-2

Zooplankton

Fig. 13-2

Nekton active swimmers

Fig. 13-4

Benthos bottom dwellers Epifauna Infauna Nektobenthos

Fig. 13-5

Marine life Marine environment stable

No need to adapt to many different conditions

98% benthic 2% pelagic

Adaptations to ocean: Viscosity

Buoyancy Cooler water more viscous Warmer water less viscous

Organisms with appendages Common warmer water Less common cooler water

Small size resists sinking

Small size resists sinking for plankton

Nekton streamlined

Fig. 13-10

Temperature Stenothermal

Open ocean, deeper Eurythermal

Shallow coastal water Open ocean, surface

Salinity Euryhaline Stenohaline

Marine hypotonic fish Drink water Secrete salt Concentrated urine Fig. 13-14

Diffusion Molecules

move from higher concentration of substance to lower concentration

Fig. 13-12b

Osmosis Water

molecules move through semipermeable membrane from less concentrated to more concentratedFig. 13-13

Dissolved gases Gas solubility depends on

temperature Gills exchange oxygen and

carbon dioxide in water Marine animals die if not

enough oxygen in seawater

Water is very transparent Shallow water fish good vision Transparent bodies (jellyfish) Counter shading Disruptive coloration Cryptic Coloration Bioluminescent

Pelagic (open ocean) Biozones

Neritic Oceanic

Epipelagic Mesopelagic Bathypelagic Abyssopelag

ic Fig. 13-19

Sunlight zones

Euphotic Disphotic Asphotic

Benthic biozones Subneritic Suboceanic

Littoral Sublittoral Abyssal Hadal

End of Chapter 13: The Marine Habitat