Final answer:
Ciliates have two types of nuclei - macronuclei and micronuclei, with the latter playing a role in reproduction and the former in cellular metabolism.
Step-by-step explanation:
Ciliates have two different nuclei - macronuclei and micronuclei. The macronucleus directs cellular metabolism and is essential for asexual binary fission and other biological functions. In contrast, the micronucleus plays a critical role in sexual reproduction but does not get transcribed during typical cellular activities such as metabolism. An example of a ciliate that has both a macronucleus and a micronucleus is Paramecium. During the process of conjugation, ciliates exchange genetic material through a complex sequence involving the micronuclei, which helps maintain genetic diversity within the species.