Q 01/05

What primary mineral compound forms the rigid structure of most coral reefs?

A) Silicon dioxide

B) Calcium phosphate

C) Calcium carbonate

D) Magnesium sulfate

Answer · why

C) Calcium carbonate

Calcium carbonate: polyps draw dissolved calcium from seawater and lay it down as rock beneath them, so a reef is mostly old skeleton under a thin liv...

Q 02/05

To which phylum of animals do corals belong?

A) Cnidaria

B) Arthropoda

C) Mollusca

D) Echinodermata

Answer · why

A) Cnidaria

Cnidaria: corals share the phylum with jellyfish and sea anemones, and like them fire stinging cells from their tentacles to catch passing prey, mostl...

Q 03/05

What is the name of the microscopic algae that live symbiotically within coral tissues?

A) Zooxanthellae

B) Chlorophyta

C) Diatoms

D) Cyanobacteria

Answer · why

A) Zooxanthellae

Zooxanthellae live inside the coral's own cells and hand over sugars made by photosynthesis, supplying up to 90% of the energy the coral needs.

Q 04/05

Which animated film's young hero is taken from the Great Barrier Reef to a fish tank in a Sydney dentist's office?

A) Shark Tale

B) Finding Nemo

C) The Little Mermaid

D) Moana

Answer · why

B) Finding Nemo

Finding Nemo sends his father Marlin south to Sydney on the East Australian Current, a real flow of warm water that sweeps down the coast from the ree...

Q 05/05

What term describes heat-stressed corals expelling the symbiotic algae that live in their tissues?

A) Coral spawning

B) Coral budding

C) Coral bleaching

D) Coral fragmentation

Answer · why

C) Coral bleaching

Coral bleaching is the loss of symbiotic algae and their pigments; the coral turns white and, if conditions do not improve, often starves.