315,744 views
12 votes
12 votes
Which of the following statements about dinoflagellates is true? Select one: A. All known varieties are autotrophic. B. Their walls are usually composed of silica plates. C. Many types lack mitochondria. D. Some produce toxic agents in the water E. Their dead cells accumulate on the seafloor, and are mined to serve as a filtering material.

User Eugeny Pavlenko
by
2.4k points

2 Answers

20 votes
20 votes

Final answer:

The true statement about dinoflagellates is that some of them produce toxic agents in the water. They are diverse unicellular protists that can have different forms of nutrition and movement and can release neurotoxins causing ecological damage.

Step-by-step explanation:

The correct answer to the question 'Which of the following statements about dinoflagellates is true?' is D. Some produce toxic agents in the water. Dinoflagellates are a group of unicellular protists that exhibit a high degree of diversity in form and function. They can be autotrophic, heterotrophic, or mixotrophic. While many dinoflagellates are encased in cellulose armor and utilize two flagella for movement, creating a spinning motion, it is also well-known that some dinoflagellates produce neurotoxins that can be harmful to fish, invertebrates, and even humans. These toxins can be released into marine or freshwater environments and can cause serious ecological disruptions, as seen in harmful algal blooms.

User Kushagra Sharma
by
3.5k points
24 votes
24 votes

Answer: The correct option is D(Some produce toxic agents in the water).

Step-by-step explanation:

Dinoflagellates are found in the phylum Dinoflagellata which are single celled organisms. They are mostly found in the ocean while few of them can live in streams, freshwater ponds and rivers. The following characteristics can be used to identify a Dinoflagellates, these include:

--> they are golden brown

--> they possess assimilative cell with indented waist.

--> they possess large nucleus with visible chromosomes.

It has been reported that many dinoflagellate species can produce various natural toxins. These toxins can be extremely toxic and many of them are effective at far lower dosages than conventional chemical agents. Therefore the option, Some produce toxic agents in the water, is a correct statement.

User Beowulfenator
by
2.3k points