Our Chemotaxis lab asks: Why do Tetrahymena engage in sexual reproduction only when starved?
Good question!
The tetrahymena do an alternation between asexual and sexual stages. In nutrient rich media during vegetative growth cells reproduce asexually by binary fission, it means when there is favourable conditions, the organisim will try increase in maximum number. Asexual reproduction by fission is faster, less energy is required so it will perform asexual reproduction.
But when conditions are unfavorable like Lack of nutrients, space and environmental conditions then it will shift to sexual reproduction so that it can led to variations and may help in survival of Tetrahymena. So, during the starvation conditions cells perform sexual conjugation, i.e pairing and fusing with a cell of opposite mating type.
I hope it helps :)
Our Chemotaxis lab asks: Why do Tetrahymena engage in sexual reproduction only when starved?