The Ultimate Coral Reef Quiz

By: Staff

4 Min Quiz

Image: refer to hsw

About This Quiz

For an underwater tourist, whether in a wetsuit or in front of a TV, a major attraction is a coral reef, an amazing ecosystem inhabited by myriad colorful marine creatures. Unfortunately, coral reefs are in danger of disappearing unless immediate steps are taken to preserve this natural wonder. Take this quiz to learn more about what needs to be done.

What is a coral reef?

Coral reefs are made mainly from stony corals and are supported by the limestone skeletons they discharge.


How long will it be until an estimated 70 percent of coral reefs disappear?

It is estimated that this will happen within 40 years.


Does a coral reef contribute to the environment?

The reef buffets coastal regions from powerful waves and storms.


How big is a single coral?

It is only 3 millimeters long.


What is a polyp?

A polyp is an individual coral


Is the coral a plant?

The coral, although it is fixed to one spot, is a living creature.


What does sessile mean?

The term comes from the Latin for "sitting" and means without a stalk, attached at the base; in other words fixed in place. It usually refers to plants but also to corals, barnacles and mussels.


Why did scientists originally think corals were plants?

When branching corals spread out their tentacles, they resemble trees with branches.


What is common to the jellyfish, sea anemone and the coral?

They are all related and are carnivorous.


Since it cannot move from place to place, how does the coral hunt for prey?

It is a passive hunter, capturing small fish and other marine life that happens to encounter its tentacles waving gently in the current.


Why could you consider a coral a half-plant?

There are algae living in the cell walls supplying it with byproducts of photosynthesis, which the coral turns into proteins, fats and carbohydrates.


What do algae gain from coral?

The coral offers shelter and provides the algae with carbon, nitrates and phosphates they need.


What is this useful arrangement known as?

This mutually beneficent arrangement is known as symbiosis.


What is the substance the polyps secrete?

They secrete calcium carbonate or limestone.


To what use is this substance put?

The limestone creates a protective skeleton and a hollow chamber into which the polyps retreat in time of danger.


How many polyps can be found in a single branching coral?

A single branching coral can have thousands of individual polyps.


When polyps join together into a colony what happens to them?

The whole colony operates as a single organism.


Do polyps reproduce?

Polyps reproduce both by dividing thereby producing identical clones (asexually) or by sending out eggs or sperm (sexually).


How is a new colony formed?

New coral polyps sink downwards until they reach a hard substrate to which they can become attached. They can join an existing colony or reef or begin a new project.


What do coral reefs need to survive and flourish?

They require sunlight, and warm water of a certain salinity.


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