AP BIOLOGY

Detailed explanation-1: -The number of contractile vacuoles per cell varies, depending on the species. Amoeba have one, Dictyostelium discoideum, Paramecium aurelia and Chlamydomonas reinhardtii have two, and giant amoeba, such as Chaos carolinensis, have many.

Detailed explanation-2: -Paramecia have two kinds of nuclei: a large ellipsoidal nucleus called a macronucleus and at least one small nucleus called a micronucleus.

Detailed explanation-3: -Abstract. The contractile vacuole complex is a membrane-bound osmoregulatory organelle of fresh water protozoa such as Paramecium. In Paramecium it consists of a central vacuole (the contractile vacuole) and 5-10 arms that radially extend from the vacuole into the cytosol (the radial arms).

Detailed explanation-4: -The haploid nuclei of each conjugant then fuse together to form diploid micronuclei and cross-fertilization takes place. The conjugants separate to form exconjugants. They are identical, but different from the earlier cells. Each exconjugate undergoes further division and forms 4 daughter Paramecia.