Download Chapter 1 - The Ocean as a Habitat

Chapter 1
The Ocean as a Habitat
I.
The Changing Marine Environment
A. Age of the Earth
B. Formation of the Earth
1. Origin of material
2. Role of gravity, pressure, and heat (Where did heat come from?)
3. Structure of the Earth
a. Atmosphere and hydrosphere
b. Continental crust and oceanic crust
c. Density-layering (Figure 1.2, page 5)
C. Role of volcanic vents in the formation of the atmosphere
D. Formation of the primitive oceans
1. Vents
2. “Snowballs”
3. Chemical composition of the primitive ocean
E. Ocean basins and ocean water have changed over time
F. Evolution of Life on Earth
1. Heterotrophs and autotrophs
2. Photosynthesis and chemosynthesis
G. Changes in atmospheric composition due to photosynthesis
Milestones in the development of life on Earth: Figure 1.3, page 6
II. Charting the Deep: A History of Marine Exploration
http://www.meer.org/mbhist.htm
A.
B.
C.
D.
Reasons for marine exploration
By the 15th century, the oceans had been charted and all inhabitable lands were occupied
James Cook and the Endeavour
H.M.S. Challenger
III. A Different View of the Ocean Floor
A. The theory of continental drift
1. Observations: the continents fit together
2. Proposed in the 1930’s by Alfred Wegener
3. Not widely accepted until the 1960’s
B. Mechanisms for continental drift: seafloor spreading and plate tectonics
C. Major tectonic plates (Figure 1.5, page 9)
1. Density of plates
2. Relationship between crust and mantle
3. What is found at the margins of the plates?
4. What happens to the plates at ridges and trenches (Figure 1.6, page 9)
5. Volcanoes, earthquakes, and tsunamis
D. How the continents have changed (Figure 1.8, page 10)
E. Other forces that have affected the oceans
1. Glaciation
2. Global warming
IV. The World Ocean
A. Earth is the only planet in the solar system with liquid water at the surface
1. Where is all the water on Earth found?
2. How much of the planet’s surface is covered by ocean? (Figure 1.9, page 11)
3. Average depth of the ocean
B. Visualizing the World Ocean
1. Geography of the Ocean Basins (Table 1.1, page 13)
2. What are the seven seas?
3. Comparing the northern hemisphere and the southern hemisphere
4. Comparing the tropical and temperate zones
C. Physiographic Provinces
1. The continental shelf, shelf break, and the continental slope
2. Abyssal plains
3. Oceanic ridge and ocean rise systems
4. Trenches
a. What is the deepest trench in the ocean? How deep is it?
b. Conditions in the trenches
5. Oceanic islands, seamounts, and abyssal hills
V. Seeing in the Dark
A. SONAR technology
1. Multiple-beam sonar systems
2. Side-scan sonar systems
Properties of Seawater
VI. Interactions between aquatic organisms and water
A. Water is crucial to the survival and well-being of marine organisms
1. Medium for many chemical reactions
2. 80-90% of body volume
3. Buoyancy
4. Support
B. How aquatic organisms affect their environment
1. Chemical composition
2. Transparency
3. Water movement
VII. Pure Water
A. Structure (figure 1.13, page 15)
B. Polarization and solvent action (figure 1.17, page 18)
C. Hydrogen bonding (figure 1.14, page 15)
1. Specific heat (figure 1.16, page 17)
a. Latent heat of vaporization
b. Latent heat of fusion
2. Viscosity
3. Surface tension
D. Density-temperature relationships
VIII. Sea water
A. Dissolved components
1. Inorganic substances (table 1.3, page 20)
a. Range of values
b. Global variation (figure 1.18, page 19)
c. Four primary factors affecting salinity (figure 1.19, page 20)
B.
C.
D.
E.
F.
2. Dissolved gases
3. Organic compounds
Salt and water balance
1. Homeostasis
2. Movement of materials across selectively permeable membranes
a. Diffusion
b. Osmosis
3. Osmoregulatory mechanisms (figure 1.20, page 21)
Light
1. Electromagnetic spectrum (figure 1.22, page 23)
2. Attenuation of light in the atmosphere
3. Attenuation of light below the water’s surface (Figure 1.21, page 22)
a. Causes
b. Change in color
c. Photic zone (figure 1.23, page 23)
Temperature
1. Range of temperatures on Earth (figure 1.24, page 24)
2. Range of temperatures at the sea surface
3. Effect on organisms
a. Metabolism
b. Activity
4. Poikilotherms vs. homeotherms
5. Global sea surface temperatures (figure 1.27, page 25)
6. Global warming
a. Causes
b. General effect
c. Effect on oceans
d. Role of the ocean in moderating global warming
Salinity-temperature-density
1. Effect of salinity on density
2. Effect of temperature on density
3. Combined effect of salinity and temperature (figure 1.29, page 27)
4. Thermocline and pycnocline
a. Formation
b. Conditions above and below the pycnocline
b. Water circulation (tropics vs. temperate oceans)
Water pressure
1. Increase with depth
2. Adaptations of plants, fish, and mammals