Final answer:
The macronucleus controls everyday cellular functions and asexual reproduction, while the micronucleus is involved in sexual reproduction in ciliated protozoa like Paramecium.
Step-by-step explanation:
The primary function of the macronucleus in ciliated protozoa like Paramecium is to direct a sexual binary fission and all other biological functions, while the micronucleus is crucial for sexual reproduction. The macronucleus is considered a multiploid nucleus that is constructed from the micronucleus during sexual reproduction process known as conjugation.
The micronucleus houses genetic information that is essential for sexual reproduction, undergoing meiosis and then restructuring to form a new macronucleus, which manages everyday cellular operations. The micronucleus and macronucleus work in tandem during the conjugation cycle to ensure both survival through asexual reproduction and genetic diversity through sexual reproduction.