a cell is the smallest structural and functional unit of an organism
The answer is letter D. The macronucleus is not exchanged during conjugation. <span>It normally contains the working duplicates/copies of genes necessary to support an enormous cell. Macronucleus is formed by a direct division of the polyploid nucleus right after conjugation then followed by series of internal gene replication that is not oftenly occurring in micronucleuse.</span>
