Best Answer: Crossing-over is another name for recombination or physical exchange of equal pieces of adjacent non-sister chromatids. When crossing-over occurs chromatids break and may be reattached to a different homologous chromosome. This occurs during Meiosis 1 / Prophase 1. Synapsis occurs when homologous chromosomes form tetrads and crossing-over or recombination takes place.
The best time to apply castor oil is at night, preferably couple of hours before bed time. While it is perfectly fine to use them during day time, there is a big advantage in applying them at night as this allows more time to saturate and start the process which aids in growing eyelashes.
Castor oil is good to treat styes (oil gland infections found on the eyelid), apply a small drop with a fingertip 2-3 times a day. Castor oil is a natural emollient and stimulates production of collagen and elastin, which hydrates the skin making it appear smoother and softer. Great when used for wrinkles and age spots. The high vitamin E content in castor oil is excellent for brittle nails and ragged cuticles.