Question

multiple choice 6.15 points what substance exists in the test of diatoms and radiolarians? iron silica calcium carbonate chitin

Explanation:

Diatoms and radiolarians have tests (shell - like structures) made of silica. Iron is not a major component of their tests. Calcium carbonate is found in the shells of some other organisms like foraminifera. Chitin is a component of the exoskeletons of arthropods and cell walls of some fungi, not of diatom and radiolarian tests.

Answer:

B. Silica