Question

What is the meaning of coral bleaching?
(A) Paling of coral colour or decline in zooxanthellae due to climate change
(B) Impacts of excessive sea trade on fishing industry
(C) Both (A) and (B)
(D) None of the above

Answer 1

Hint : Coral bleaching is related to the loss of colours of corals and turning into white. Coral are one type of living organism that live in deep sea and they belong to the class anthozoa in the animal phylum cnidaria. Corals keep marine species alive by releasing oxygen just like trees.

Complete Step By Step Answer:
The correct answer to this question is option A, coral bleaching means paling of coral colour or decline in zooxanthellae due to climate change.
The coral are one kind of living organisms living in the deep sea providing oxygen to marine life. Coral polyps have algae inside their tissue, this algae provide most of the energy for corals to live and due to presence of this algae inside their tissue the corals show different and vibrant colours.
When the temperature of the sea rises, the algae residing inside the corals leave it and thus the colour of corals also gets washed off. Thus the corals become white and therefore the process is called coral bleaching.
The main reason for the rising temperature of the ocean is climate change. Due to the increase in temperature of the atmosphere, the temperature of oceans and seas also increase, and thus coral bleaching occurs.
A temperature rise of only one degree Celsius can cause coral bleaching. The algae that reside inside the tissues of corals is called zooxanthellae, thus declination of the algae makes the coral leave its colour.
Not only that, corals could effectively die if the algae leaves the corals for a long time as the algae provides the coral most of its energy.

Note :
Zooxanthellae is a microscopic algae and it has a symbiotic relationship with the corals. Coral bleaching does not only occur due to climate change, it can also occur because of extremely low tides, sea pollution or too much sunlight. Corals are extremely important to the world as once they die, they rarely come back. Most of the wildlife depends upon the coral reefs, and without marine life human beings cannot live.