The aura can be in the form of prismatic colors, flashes of light, and sometimes stars. They usually last about 20 minutes and then go away. If these flashes or lines of light occur without a headache, it is called an ophthalmic migraine, or a migraine without a headache.
In gymnosperms and flowering plants, the megaspore is produced inside the nucellus of the ovule. During megasporogenesis, a diploid precursor cell, the megasporocyte or megaspore mother cell, undergoes meiosis to produce initially four haploid cells (the megaspores).
Only eukaryotic cells can undergo meiosis. When a cell undergoes meiosis, a form of cell division occurs that produces daughter cells with half of the species'â¦ usual number of chromosomes, or haploid cells. These resulting daughter cells are gametes and aid the organism in sexual reproduction.