Thursday, February 21, 2008


Corals reefs in Papua New Guinea.

I was more than pleased with the speeches I heard mainly because of the effort made , ideas stated and the way you backed up your points of view and reasoned the questions that arose. Then we started to deal with some specific vocabulary related to travelling. It is obviously more to study, so I removed quite a good number of items from the glossary: those related to the workbook (not the listening exercise) and those of the exercise called Where´s my Car?. As we carry on with the unit, we´ll go through the glossary again. A listening activity in your workbooks ,page 43, about a trip that went wrong .You had to order the sequence of events, note down time expressions and spot differences. With the first group we had time for a speaking activity, anecdote, in your book ,page 70, A Holiday you Went on when you were a child.Group C will do it later next week.

For homework, please, start doing unit 7 exercises in your workbook.

Coral reefs are structures produced by living organisms, found in shallow, tropical marine waters In most reefs, the predominant organisms are stony corals, colonial cnidarians that secrete an exoskeleton of limestone. The accumulation of this material, broken and piled up by waves, produces a huge calcareous formation that supports the living corals and a great variety of other animal and plants. corals are found both in temperate and tropical waters.

Waves, coral eating fish such as parrot fish,sea urchins, and other organisms break down the coral skeletons into fragments that settle in the reef . Algae (i.e zooxanthelate) are important contributors to the structure of the reef . These algae contribute to reef-building by depositing limestone over the surface of the reef and contributing also to the structure of the reef.

Corals have symbiotic relationships with algae called zooxantellae; these algae placed in the coral polyps carry out photosynthesis and produce organic nutrients that are then used by the coral polyps. Because of this relationship, coral reefs grow much faster in clear water with more sunlight.