The Dictyostelia social amoebas are found in a wide range of soil habitats. They can come together to form a fruiting structure, in which a proportion of cells are sacrificed to build the stalk and the remainder differentiate into resilient dormant spores. This multicellular life cycle is common to all Dictyostelids. It consists of an interconnected programme of cell movement and cell differentiation, and has been intensively studied in the model organism D. discoideum. Few mutants (Column A) and phenotypes (Column B) are listed in the table given below. Column A Column B A. Loss of function of cAMP-dependent protein kinase (PKA) i. cell develop normally but unable to germinate B. Loss of function of RegA ii. Loose aggregate form C. Loss of function of adenylate cyclase B iii. No aggregation D. Loss of function of gp80 iv. accumulation of cAMP and PKA activation Match the correct mutant with the observed phenotype. -triyambak.org