corals Flashcards
describe modern coral morphology
polyps consists of 2 layers, outer +inner endoderm, with stinging cells called nematoblasts
laval stage- free swimming, attach themselves to hard substrate, polyp secrete calcium carbonate skeleton
solitary or compound
describe the symbiotic relationship of coral
Algae live inside tissue. Algae photosynthesises + takes waste from coral to make oxygen, water, amino acids and sugars. coral uses waste from algae. Cannot live without each other.
what is the name of the Algae that lives inside modern corals?
Zooxanthellae
why do corals need to be at or just below sea level?
Light can reach coral for algae to photosynthesise
why do corals need clear water?
sunlight for algae to survive
why do corals need particle free water?
particles may clog polyp
why do corals need to be in areas of high energy or wave action?
incorporates more oxygen into the water and circulate the correct level of nutrients by upwelling
what salinity do corals need to survive?
30-40 parts per thousand
what temps to corals need and what happens if the temp is too high?
23-29 c
otherwise coral bleaching occurs
geological range of rugose corals
Ordovician- Permian (extinct)
geological range of tabulate corals
Cambrian to Permian (extinct)
geological range of scleractinian corals
Triassic to recent (extant)
how is undigested food removed?
though the mouth (no anus)
how do corals feed?
Polyp has tentacles it extends at night. Food particles in water are extracted. Sometimes paralyse prey using acid from nematoblasts or may become trapped in mucus secreted by polyp. Food passed to mouth + into primitive gut for digestion.
what is the phylum and class of modern coral?
phylum: Cnidaria
class: Anthozoa
