What is the nature of cell-walls in diatoms?
Solution and Explanation
The cell walls of diatoms are made of silica. Their cell wall construction is known as frustule. It consists of two thin overlapping shells that fit into each other such as a soap box. When the diatoms die, the silica in their cell walls gets deposited in the form of diatomaceous earth. This diatomaceous earth is very soft and quite inert. It is used in filtration of oils, sugars, and for other industrial purposes.
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Concepts Used:
Kingdom Protista
Biological Classification: Kingdom Protista
Protista is the kingdom that includes single-celled eukaryotes. They are typically found in the water. In the aquatic ecosystem, algae, for example, are the primary producers. They are eukaryotic creatures with only one cell. They have a true core that is separated from the rest of the cell by the nuclear membrane. They can move by cilia and flagella; they can breathe both aerobically and anaerobically, and they can reproduce both sexually and asexually.
Characteristics of Kingdom Protista:
- They are eukaryotic, which means they have a nucleus.
- Most have mitochondria.
- They can be parasites.
- They all prefer aquatic or moist environments.
Read More: Biological Classification
Classification of Protista
They are divided into Chrysophytes, Dinoflagellates, Euglenoids, Slime molds, and Protozoans.
Chrysophytes
This category includes diatoms and golden algae. They are found in both freshwater and marine settings. In nature, they are photosynthetic. Their cell walls are made of silica. They are the most important producers in the oceans. Most of them are unicellular flagellates. They are amoeboids.
Dinoflagellates
They are photosynthetic organisms that live in the sea. They can be yellow, green, brown, blue, or red, depending on the cell pigment. The outside surface of their cell walls is covered in cellulose plates, making them rigid.
Euglenoids
They are frequently found in stagnant water and are freshwater creatures. They make use of their photosynthetic nature when exposed to sunshine. They eat smaller organisms when they are deprived of sunshine.
Slime Moulds
They feed on rotting twigs, leaves, and organic waste and are saprophytic. Even in the face of adversity, they can live for a long time.
Protozoans
All protozoans are parasite-eating predators. Amoeboid protozoans, Flagellated protozoans, Ciliated protozoans, and Sporozoans are the four types of protozoans.