SDSU OCEAN 100 FINAL SACRAMENTOGRILO
QUESTIONS AND ANSWERS
origin of earth - Answers - • Supernova: death of a star (great explosion)
• Supernova happened 4.6 bya, dust and gas flattens to a disk and spins faster due to
gravity and solar nebula formed.
• Solar Nebula: describes formation of Earth 4.5 bya
• Nebula: gas cloud
origin of oceans - Answers - • volcanic explosion, H2O condensed and rained down for
thousands of years to create oceans
• icy comets hitting earth (responsible for 1/2 of earths ocean water)
origin of life - Answers - • 4.5 bya solar system formed
• about 4 billion years ago bacteria (in rocks)
• 2.5 bya photosynthetic organisms (algae) formed and put out O2 which lead to the
development of plants which put out O2 leading to development of animals
• 600 mya animals
earths internal layers - Answers - • lithosphere:
- outermost layer of earth
- first 100km of crust
- strong, rigid, brittle
- contains all the crust and outermost layer of the mantle
• asthenosphere:
- plastic, 600km
- upper mantle
- very hot
- allows plates to move over it
-ductile
- directly below lithosphere
• mesosphere:
- lower mantle
- outer core (liquid) + inner core (rigid)
,Energy - Answers - • kinetic: energy of motion
• heat: movement from hot to cold
- sources → sun, geothermal (heat from within the earth)
• kinetic + heat energy drive everything that happens on the surface of the earth
density - Answers - • the relationship between mass and volume
• colder water = more dense (molecules closer together)
- thermal contraction
- polar & sub polar regions
- lower energy
• warmer water = less dense (molecules are farther part)
- thermal expansion
- equatorial & sub equatorial regions
- high energy
• oceanic crust (basalt) denser than continental crust (granite)
convection - Answers - • movement of liquid, gas, & viscous solid
• hot, less dense air/water rises
, •cold, more dense air/water sinks
bioaccumulation - Answers - • the build up of a substance (usually a toxin) as it passes
through a food chain
• top of the food chain has most concentration of substance (mercury for example)
biodegradation - Answers - • the breaking down of dead organic matter by living
organisms such as bacteria
• biodegradable → nature can break it down
photo-degradation - Answers - a polymer that can be broken down by the sun (like
plastic)
diffusion - Answers - • movement of molecules from an area of higher concentration to
an area of lower concentration
• oxygen enters fishes gills at a high concentration from water to low concentration in
their blood
plate tectonic principles (evidence?) - Answers - 1. continental drift
• pangea (super continent during early years of Earth)
• break up of continent → asthenosphere melts & pushes land apart
2. echo sounding & sonar
• shallowest in the middle of oceans
3. seafloor spreading
• mid-ocean ridges
• rocks rise from center & creates plates
4. age of seafloor
• youngest → mid ocean ridges
• oldest → closer to continents
5. earths magnetic field
• rocks at ridges capture the energy of magnetic fields
6. distribution of earthquakes
• most at pacific rim
• generally happen at plate boundaries
7. distribution of volcanoes
• near pacific rim (pacific rim of fire)
QUESTIONS AND ANSWERS
origin of earth - Answers - • Supernova: death of a star (great explosion)
• Supernova happened 4.6 bya, dust and gas flattens to a disk and spins faster due to
gravity and solar nebula formed.
• Solar Nebula: describes formation of Earth 4.5 bya
• Nebula: gas cloud
origin of oceans - Answers - • volcanic explosion, H2O condensed and rained down for
thousands of years to create oceans
• icy comets hitting earth (responsible for 1/2 of earths ocean water)
origin of life - Answers - • 4.5 bya solar system formed
• about 4 billion years ago bacteria (in rocks)
• 2.5 bya photosynthetic organisms (algae) formed and put out O2 which lead to the
development of plants which put out O2 leading to development of animals
• 600 mya animals
earths internal layers - Answers - • lithosphere:
- outermost layer of earth
- first 100km of crust
- strong, rigid, brittle
- contains all the crust and outermost layer of the mantle
• asthenosphere:
- plastic, 600km
- upper mantle
- very hot
- allows plates to move over it
-ductile
- directly below lithosphere
• mesosphere:
- lower mantle
- outer core (liquid) + inner core (rigid)
,Energy - Answers - • kinetic: energy of motion
• heat: movement from hot to cold
- sources → sun, geothermal (heat from within the earth)
• kinetic + heat energy drive everything that happens on the surface of the earth
density - Answers - • the relationship between mass and volume
• colder water = more dense (molecules closer together)
- thermal contraction
- polar & sub polar regions
- lower energy
• warmer water = less dense (molecules are farther part)
- thermal expansion
- equatorial & sub equatorial regions
- high energy
• oceanic crust (basalt) denser than continental crust (granite)
convection - Answers - • movement of liquid, gas, & viscous solid
• hot, less dense air/water rises
, •cold, more dense air/water sinks
bioaccumulation - Answers - • the build up of a substance (usually a toxin) as it passes
through a food chain
• top of the food chain has most concentration of substance (mercury for example)
biodegradation - Answers - • the breaking down of dead organic matter by living
organisms such as bacteria
• biodegradable → nature can break it down
photo-degradation - Answers - a polymer that can be broken down by the sun (like
plastic)
diffusion - Answers - • movement of molecules from an area of higher concentration to
an area of lower concentration
• oxygen enters fishes gills at a high concentration from water to low concentration in
their blood
plate tectonic principles (evidence?) - Answers - 1. continental drift
• pangea (super continent during early years of Earth)
• break up of continent → asthenosphere melts & pushes land apart
2. echo sounding & sonar
• shallowest in the middle of oceans
3. seafloor spreading
• mid-ocean ridges
• rocks rise from center & creates plates
4. age of seafloor
• youngest → mid ocean ridges
• oldest → closer to continents
5. earths magnetic field
• rocks at ridges capture the energy of magnetic fields
6. distribution of earthquakes
• most at pacific rim
• generally happen at plate boundaries
7. distribution of volcanoes
• near pacific rim (pacific rim of fire)
