Final answer:
Sarcodina reproduce mainly asexually through mitosis, some like Dictyostelium also form multicellular structures that reproduce asexually. Rarely, sexual reproduction can occur with the fusion of two amoeboid cells. Other related protists might follow complex processes like conjugation, exemplified by Paramecium.
Step-by-step explanation:
Sarcodina, such as amoebas, reproduce asexually through mitosis. In their life cycle, individual amoeboid cells divide by mitosis to reproduce. However, in species like Dictyostelium, multicellular aggregates also reproduce asexually through a sequence beginning with a slug that forms a fruiting body, which in turn releases more amoeba that can form additional slugs. On rare occasions, Dictyostelium may engage in sexual reproduction when two amoeboid cells fuse together forming a diploid cell, which can lead to the formation of spores.
Other protists, such as ciliates, have a more complex method of sexual reproduction. In organisms like Paramecium, two cells join via a cytoplasmic bridge and exchange genetic material through a process called conjugation. This involves meiosis of the diploid micronucleus, the disintegration of the macronucleus, and multiple rounds of cell division to create genetically diverse offspring.
As with many microorganisms, reproduction in Sarcodina is versatile and can include a combination of asexual and, less commonly, sexual reproductive strategies.