meiosis: a one-way process.

meiosis is divided into two processes: meiosis 1 and meiosis 2. in meiosis 1, the processes interphase 1, prophase 1, metaphase 1, anaphase 1 and telophase 1 happens. while in meiosis 2, prophase 2, metaphase 2, anaphase 2, and telophase 2 takes place.

in meiosis 1, the first process to occur is the interphase 1. in interphase 1, the process starts with growth 1 where it is the very active stage in meiosis, synthesis of proteins take place, and cells are identical to somatic or body cells. then, the following stage is the synthesis in which the genetic material is duplicated, and the cell is diploid. and to complete the last interphase 1 is the growth 2 which is absent in mitosis. then, prophase 1 is next. prophase 1 is subdivided into five substages: leptotene, zygotene, pachytene, diplotene, and diakinesis. leptotene is the substage where two sister chromatids are thin and long strands, and also known as the bouquet stage. after leptotene, zygotene is the next and the chromosomes are paired and zipped together forming synaptotemal complex. next is the pachytene where thick threads and nonsister chromatids exchange segments and results in a recombination of information and synapsis is completed. after pachytene, diplotene occurs and the synaptotemal complex degrades, homologous pair separate, chromosome uncoils and chiasmata remains. to complete the prophase 1, diakinesis is accomplished where the nuclear membrane disintegrates, nucleoli disappear, chiasmata ends, and meiotic spindle forms. after prophase 1, metaphase 1 or the movement of chromosomes to the metaphase phase and the attachment of spindle fibers occur. then, anaphase 1 or continued attachment of the chromosomes to centromere and separation of chromosomes happens. and to complete the meiosis 1, telophase 1 must be finished where chromosomes are at the end poles and chromosomes have two sister chromatids.

in meiosis 2, same stages will be taken, but the difference is that the two sister cells are acting. meiosis 2 begins when the prophase 2 or the disappearing of nuclear membrane, and movement of spindle fibers oppositely. after the prophase 2 times, the metaphase 2 where chromosomes align at the center of the cell. afterwards, anaphase 2 comes next in which chromosomes split and the spindle fibers pull sister chromatids apart. after anaphase 2, telophase 2 will not be the last as the chromosomes go to the far end of the cell, the spindle disappears and the nuclei and cytoplasmic division reappears.

in this one-way process, you can think of it as clay that can be pulled from each other because you can see how they separate from each other, and you can do it twice. well. even if clay could be separated more than twice, but cells that undergo this process does it only twice. it’s God’s law. haha! :D