Question

The beautiful diatoms and desmids are placed under
(a) Chrysophytes
(b) Dinoflagellates
(c) Euglenoids
(d) Slime moulds.

Answer 1

These are a group of algae that are commonly found in lakes. They are sometimes referred to as golden-brown algae due to their colouration from specific photosynthetic pigments and belong to the Kingdom Protista.

Complete step by step answer:
The beautiful diatoms and desmids are placed under chrysophytes of the Kingdom Protista. Chrysophytes belong to the kingdom Protista. The group contains about 5500 species. They occur all together in aquatic and moist terrestrial habitats. The body is roofed by a transparent siliceous shell (silica deposited in the cell wall) referred to as frustule. The frustule is formed from two valves, epitheca, and hypotheca. the 2 valves fit together like that of a soapbox. Diatoms are vital photosynthesizers. they're excellent pollution indicators.
So, the correct answer is, ‘Chrysophytes.’

Additional Information: Difference between Diatoms and Desmids;
- Diatoms are stramenopila algae whereas Desmids are chlorophyte.
- The cell membrane of diatoms consists of silica whereas that of desmids consists of cellulose and pectins (like plants) .
- The chloroplasts of diatoms are yellowish- brown in colour whereas that of desmids are green.

Note: Important characteristics of Chrysophytes are :
- Two unequal flagella.
- Golden yellow colour due to accessory pigment.
- Cell walls made of cellulose and silica.
- They are Free swimming types of algae.
- They are Unicellular,
- Present in water bodies with low calcium levels.
- Diatoms are stramenopile algae, their cell wall is composed of silica and their chloroplasts are yellowish- brown. Desmids are a group of green algae in which their cell wall is composed of cellulose and pectins (like that of plants) , and their chloroplasts are green.