Divya Rao

Interesting Facts If an encounters a negative stimulus, it is capable of rotating up to 360 degrees to find an escape route. Paramecium can discriminate between different levels of darkness. The macronuclear DNA has a very high gene density which allows it to have 800 copies of each gene in the macronucleus. Paramecium shows galvanotropism which is the movement of paramecium as they do not turn around to go the other way but the cilia will bend and face toward the other side and swim backward.

Key Features Parameciums are heterotrophs. They commonly prey on bacteria. They capture their prey through phagocytosis. To catch food they eject trichocyts which are filled with proteins. To protect against the Didinium – its vicious enemy – it releases dart life objects from capsules that are scattered underneath their bodies. But unfortunately this method is completely ineffective to protect its self. It has a mutalistic symbiotic relationship with green algae called Zoochlorella. The algae live inside the paramecium in its cytoplasm and provides the Paramecium with food, while the Paramecium provides algae with movement.

Life Cycle Paramecium are capable of both asexual and sexual reproduction. Asexual is the most common. Binary Fission is the form of asexual reproduction where the paramecium splits itself down the middle, making two new paramecium. They perform sexual reproduction only under stressful conditions. Two paramecium bind forming a cytoplasmic bridge between them. Then the micronucleus of the paramecium undergoes meiosis. Four nuclei are formed, three disintegrate and the other duplicates by mitosis. The daughter nucleus moves across the bridge and fuses with the other daughter nucleus to for a diploid nucleus. Then the cells separate. The old macronucleus disintegrates and a new one is formed from the micronucleus.

Uses They are used in genetic engineering because they have the ability to reproduce quickly sometimes even three or four times a day. They help with the carbon cycle. As they eat bacteria which live on plants and these bacteria decompose the plant matter. The paramecium help speed up that process. Carbon cycle