Coral Reef Development Flashcards
What are the two main coral groups?
Alcyonacea ‘soft corals’ and Scleractinia ‘hard corals
What are the two morphological groups within Scleractinia?
reef-forming/hermatypic and non-reef forming/ahermatypic
do you know how to use and make a dichotomous key?
Totally
NEEDS TO ADD PIC FOR LABELLING CORAL PARTS
How is a limestone skeleton of a coral formed?
when calcium ions [Ca2+] combine with carbonate ions [CO32–]
What is the process of coral feeding?
During the day the zooxanthallae within the coral photosynthesise producing the majority of food and night the nematocysts within the coral polyps sting, immobilise or kill zooplankton which is then consumed through the polyp’s mouth. Some may also absorb of capture organic matter.
What is the relationship between coral and zooxanthallae?
Mutualism as coral provides zooxanthallae with shelter and the zooxanthallae provides coral with 95% of their energy through photosynthesis.
What are the lifestages of a asexual and sexual reproduction typical reef-forming hard coral?
Sexual- gametes, zygotes, planulae, polyp/asexual budding
asexual- fragmentation, polyp detachment
What is the requirement in terms of accretion and erosion for coral reef growth?
A coral reef requires the rate of accretion to be greater than the rate of erosion.
What is accretion?
The growth of coral substrate due to calcification rate.
What is chemical erosion?
The CaCO3 is dissolved with acidic chemicals
explain the process of larval dispersal, site selection, settlement and recruitment
Larval dispersal- planktonic coral larvae is distributed throughout the reef
Site selection- Coral planula investigates and choses a site for settlement
Settlement- The coral planula attaches to the chosen substrate and develops into a polyp
Recruitment- Coral polyp establishes itself as a member of the reef community
