Algae simple plants that mostly live in water examples include microscopic single cells and seaweed.

Biodiversity all the living species of animals, plants, bacteria and other organisms, their total genetic diversity and the diversity of all the ecosystems.

Carbon dioxide a gas consisting of a chemical made from carbon and oxygen atoms. One of its properties is it can retain heat longer than oxygen and nitrogen.

Climate is the average weather over a number of years and shows what the average trend in weather is over all the seasons.

Greenhouse gas any gas liberated into the atmosphere that holds onto heat longer than oxygen and nitrogen.

Limestone a hard rocklike white chemical made by coral polyps. Its chemical name is calcium carbonate.

Methane is a gas made from carbon and hydrogen. It is also known as natural gas and is used as a fuel. When it escapes into the atmosphere it takes at least 100 years for it to break down. One of its properties is it can retain heat longer than oxygen and nitrogen.

Ozone a gas that filters ultraviolet radiation in the upper atmosphere. Ozone in the lower atmosphere is a pollutant that can affect the health of living organisms.

Phytoplankton microscopic plants (algae) that float or swim in water. The sunlight can only penetrate into the first 60 metres of clean water for most of these plants to grow.

Polyp small simple creature with a mouth, gut and tentacles. It has no brain, eyes heart or blood vessels.

Radula rasping teeth in the mouth of seashells.

Symbiotic relationship describes two unrelated organisms that live with each other and both obtain benefits from their relationship.

Ultraviolet radiation (UV) very short wavelengths of light (radiation) that can damage living organisms.

Weather describes the changes in rain, sun, cloud, wind, temperature etc. form hour to hour, day to day and month to month.

Zooplankton simple microscopic animals that feed on phytoplankton (microscopic algae) or even smaller zooplankton. These tiny animals are the essential link to feed the animals further up the food chain.

Zooxanthellae a particular group of microscopic algae that can live and swim freely in the sea and also live in the cells of coral polyps and clams.