The enzymes responsible for the Calvin-Benson pathway of photosynthesis are found a. within the thylakoid membranes. A checkpoint exists after DNA replication has occurred. Homologous chromosomes cross over. Chromatids separate prior to being moved by the spindle apparatus to different regions of the cell. The DNA of the nucleus replicates prior to the cell committing to divide.
Some organisms are capable of asexual or sexual reproduction.
Under favorable growth conditions, asexual reproduction generally occurs, but when life gets tough, the organism switches to sexual reproduction. Sexual reproduction is simpler and more rapid, allowing a larger number of offspring to be produced in a shorter period of time. Sexual reproduction produces individuals with new combinations of recombined chromosomes. Sexual reproduction allows pooling of nutrient resources from two organisms, thereby enhancing the amount of nutrients provided to the gamete. In Meiosis II, the chromatids of a given chromosome are virtually identical.