Diatomaceous earth is a result of accumulation of cell wall deposits of diatoms over

1. Billions of years
2. Millions of years
3. Thousands of years
4. Hundreds of years

Which of the following feature is not associated with diatoms?

1. Chief producers of Earth
2. Form diatomaceous earth which has gritty soil
3. Gritty soil is used in filteration
4. Gritty soil is used in polishing

Red tides in the sea are because of

1. Red dinoflagellates
2. Geladium
3. Red Chrysophytes
4. Red algae

Dinoflagellates- do not possess which feature?

1. Marine and photosynthetic
2. Variety in colors
3. Cell wall with silica
4. Two flagella

Dinoflagellates can not appear

1. Black
2. White
3. More than one option is correct
4. Pink

Which of the following property belongs to Dinoflagellates?

1. Loose cellulose plates in cell wall
2. The outer surface has more loosening of cell wall than inner
3. Rapid multiplication
4. Not harmful for others

Which of the following is not associated with red tides

1. Harmful for marine organisms
2. Gonyaulax
3. Aquatic habitat
4. Color is due to pigment in the cell of Dinoflagellates

…….of them have …..flagella  …..lie in a furrow between wall plates

1. All, 2, both
2. Many, 3, trasverse falgella
3. Most, 2, both
4. All, 3, longitudinal flagella

Pellicle is found in

1. Euglenoids
2. Dinoflagellates
3. Diatoms
4. Eubacteria

Euglenoids are not

1. Mostly marine
2. Have pellicle
3. Lack cell wall
4. Flexible body