Practice question

Foraminifera, amoeboid members of Rhizaria supergroup, construct elaborate tests or shells primarily composed of calcium carbonate secreted as calcite or aragonite, sometimes agglutinating foreign particles with organic cement, ranging from single chamber to multichambered spiral morphology. Reticulopodia extend through apertures for prey capture and locomotion. Tests accumulate as pelagic oozes forming chalk deposits, significant in marine carbon sequestration. Fossil assemblages enable paleoceanographic reconstruction and biostratigraphic dating due to abundance. Chemistry differs from siliceous skeletons of radiolaria and diatoms, reflecting distinct biomineralization pathways using calcium ATPases and carbonic anhydrase.