NOTES
Links to summaries of key issues for each topic
VISUALS
Links to images employed in lectures on a topic-by-topic basis
TEXT
Link to chapter outlines at online learning center at McGraw Hill.
NOTES
Links to summaries of key issues for each topic
|
Notes on Topic:
The notes represent summaries of key issues
for each topic
They emphasize the terminology used to describe
the various phenomena.
| 1. Physical Requirements for Marine Life: |
| Learning Objectives: |
-
Comprehension of charcteristics of marine environment relevant to biology
-
Understanding of adaptations of organisms to life in the oceans
|
| Buoyancy and Flotation, Osmotic Processes: |
-
Organisms adjustment to seawater density:
-
gases for flotation (e.g. in fronds)
-
fish use swim bladders
-
organs that contain gas (O2, CO2,
rarely N2 )
-
other fish swim constantly (sharks, rays)
-
shells with gas-filled chamber; fats/blubber; air sacs.
-
Osmosis:
-
either salinity = saltwater
-
or salt exclusion by membranes, tolerant to salinity
|
| Temperature, Pressure and Gases: |
-
Temperature adaptation, marine animals are:
-
ectotherms (cold-blooded), controlled by surroundings
-
tend to grow slower, live longer
-
endotherms (warm-blooded)
-
Pressure adaptation:
-
without gas-filled cavities:
-
no adaptation required to higher pressures in deep sea
-
air-breathing mammals:
-
changes in blood physiology needed.
-
Required gases:
-
CO2 required for photosynthesis
-
O2 required for respiration
-
Organisms may be restricted where:
-
O2 changes rapidly or is absent (anaerobic)
|
| Nutrients, Light and Color: |
-
Nutrients:
-
substances essential for plant growth
-
N as NO3, P as PO4, depleted
in surface waters
-
recycled by death and decomposition
-
within surface waters
-
below pycnocline
-
resupplied to surface by upwelling
-
Light penetrates photic zone:
-
depth dependent on sun's angle, wavelength, suspended particles
-
below aphotic zone (light levels <1%) no photosynthesis.
-
Bioluminescence:
-
produced by interaction of luciferin and enzyme luciferase (cf. firefly)
-
some organisms have light-producing organs: photophores
-
Color as protection:
-
transparent, blending, warning
-
red in deep ocean
-
schooling
-
countershading (different scale coloration)
-
variable camouflage.
|
| Cicrculation, Barriers and Boundaries: |
-
Vertical/horizontal movement of organisms
-
governed by currents, buoyancy
-
Movement of organisms restricted by:
-
water properties (temperature, salinity)
-
water flow, topography (connectivity).
|
| Bottom Types: |
-
Sea floor may provide substrate for life:
-
e.g. mud, sand, gravel, rock
-
influences organisms, especially those attached to the bottom.
|
| Environmental Zones: |
-
Oceanic life concentrated:
-
at the sea surface and on the ocean floor
-
Habitats:
-
neritic (coastal), pelagic (open ocean), or benthic (sea floor)
-
Surface waters:
-
<200m: epipelagic; 200 - 1000m mesopelagic
-
1 - 4km bathypelagic; >4km: abyssopelagic
-
Tidal regions:
-
supralittoral (splash), littoral (intertidal), sublittoral (subtidal)
-
Ocean:
-
bathyal (200m - 4km); abyssal (4 - 6km); hadal (>6km).
|
| 2. Classification of Organisms: |
| Learning Objectives: |
-
Recognition of approaches to classification of oceanic life
|
| Characteristics: |
-
Organisms may be:
-
plankton: drifting, carried by currents
-
bacteria, phytoplankton (plants) or zooplankton (animals)
-
nekton: swimmers
-
benthic: dwelling on the sea floor
-
attached plants (shallow water) and animals.
|
Department
of Geological Sciences,
1001
E. Tenth Street, Bloomington, IN 47405-1403
Phone:
(812) 855-5582 Last updated: 7 December 2000
Comments:
simon@indiana.edu
Copyright
2000, The Trustees of Indiana University
|
