EOSC 326 Final: EOSC 326 Video Notes for Final Exam.docx
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EOSC 326 Final Exam: Video Notes
Lesson 11: “Caribbean Coral Reef Biology and Ecology” (more in PDF)
A1. What forms the massive structure that is the base of this Caribbean modern coral reef?
•Calcium carbonate skeleton produced by corals
A2. What are the conditions under which corals in the reef grow best?
•Shallow tropical waters, where temperatures are warm, nutrients are scarce, and
sedimentation rates are low
A3. Why do coral morphologies differ on a reef?
•Wave strength, sedimentation, and the amount of sunlight
A4. Where in the reef are flat corals found?
•Deeper parts, where their flat morphology is ideal for capturing sunlight and food in the
A5. Where are massive and branching corals found?
•Back reef and fore reef, where light is abundant and the sedimentation rates are high
B1. What is the benefit of a coral having a massive or branching shape?
•Allows sediments to be easily removed (as wave energy kicks up sand and sediment,
corals can easily be smothered if they weren't in the right shape)
B2. Where are encrusting corals found? Why can they survive there?
•Reef crest (with breaking waves crashing upon the encrusting corals), where the
encrusting corals cement themselves tightly to the reef
Lesson 12: “Stromatolites of Hamelin Pool” (more in PDF)
1. How fast do stromatolites grow?
•5 cm in 100 years
2. How are stromatolites formed?
•Formed by microbes (cyanobacteria) that trap and bind particles together to form a net,
which then traps calcium carbonate, then the bacteria must migrate up to get the
3. Why are stromatolites able to grow around Hamelin Pool?
•Sand is blocking the pool --> high level of salinity, low level of nutrients in the pool -->
limited number of potential predators and competitors
4. What marked the first indication of increasing salinity in Hamelin Pool?
•Explosion of bivalves that formed ridges around Hamelin Pool
5. When did stromatolites first begin to form in Hamelin Pool?
•2000 years ago
6. Why are stromatolites limited to 4 metres depth in Hamelin Pool?
•Calcification cannot occur beneath 4m
7. Why are some stromatolites in Hamelin Pool now stranded in the intertidal zone?
•Fall in sea level
8. What roles do the stromatolites play for the other organisms in Hamelin Pool?
•Stromatolites provide shelter for small organisms, substrate for marine plants, and
source of food for fish and crustaceans
Lesson 12: “BBC Wildlife: The Wonderful World of the Sea Sponges”
1. Where are the sponges situated in the "Cayman Wall"?
•Sponges in the "Cayman Wall" are found at 3000 feet and below
2. Why can the sponges live so deep in the water column?
•Sponges can live so deep in the water column, because they are not dependent on
sunlight the same way that corals are and they have no competition and can
flourish/develop into wonderful shapes in order to stick themselves into the current to
grab their food
3. What do sponges eat?
•Marine snow (organic detritus)
4. How much water can a sponge filter in one day?
•1 cm3 of sponge can filter effectively over 20 L of water per day
5. How big is the "elephant ear sponge"?
•The "elephant ear sponge" is 9 feet tall