The correct answer is:
Option 1: The walls of diatoms are easily destructible
Option 1: The walls of diatoms are easily destructible: This is incorrect. Diatoms have silica-based cell walls that are quite strong and durable. These cell walls are known as frustules, and they are highly resistant to decay and damage. Their rigid and intricate structures are not easily destructible.
Option 2: 'Diatomaceous earth' is formed by the cell walls of diatoms: This is correct. Diatomaceous earth is formed from the fossilized remains of diatoms. When diatoms die, their silica-rich cell walls accumulate on the ocean floor, and over time, they form a sedimentary rock called diatomaceous earth.
Option 3: Diatoms are chief producers in the oceans: This is correct. Diatoms are photosynthetic organisms and play a key role in the marine ecosystem. They are one of the most important groups of primary producers in the ocean, contributing significantly to the marine food chain.
Option 4: Diatoms are microscopic and float passively in water: This is correct. Diatoms are microscopic algae that float passively in the water, primarily in the photic zone of the ocean. Their unique silica cell walls help them maintain buoyancy.
The wrong statement is Option 1 because diatom walls are not easily destructible; they are strong and resistant due to their silica content.
AB is a part of an electrical circuit (see figure). The potential difference \(V_A - V_B\), at the instant when current \(i = 2\) A and is increasing at a rate of 1 amp/second is:
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.
Read More: Biological Classification
They are divided into Chrysophytes, Dinoflagellates, Euglenoids, Slime molds, and Protozoans.
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.
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.
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.
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.
All protozoans are parasite-eating predators. Amoeboid protozoans, Flagellated protozoans, Ciliated protozoans, and Sporozoans are the four types of protozoans.