Which of the following is a true statement regarding phytoplankton?

they are the only cause of green ocean water
they are responsible for 80% of all global warming
they are the primary photosynthetic plants in the ocean
they are most commonly found near deep-sea thermal vents

True statement regarding phytoplankton is :

They are the primary photosynthetic plants in the ocean

Explanation:

Phytoplankton : It is made of two words :

"Phyto" means plants

"plankton" means drift .

Hence Phytoplankton  are plants that live in water .They are also known as microalgae and are similar to terrestrial plants because they also contain chlorophyll .

Most phytoplanktons are found on the surface of water so that they can get enough sunlight to prepare their food .

There are two kinds of phytoplankton

a) dinoflagellates (they have tail or flagella)

b) diatoms (they are shell like)

They provide food to many organism living in water . example : jelly fish , shrimps etc

Hence they balance the ecosystem

In this way they are primary producers in water -food chain

b is the correct answer

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