During prophase I, each of the homologous pairs of chromosomes can be seen as bivalent or as a grouping of two chromosomes said to be sister chromatids. The site at which the crossing over occurs on the sister chromatids is known as the chiasma. Prophase I is the longest phase during the meiosis process and takes up to 90 percent of the total time of cell division.
Castor beans are pressed to extract castor oil which is used for medicinal purposes. Ricin (a toxic substance present in the plant) does not partition into the oil because it is water-soluble, therefore, castor oil does not contain ricin, provided that no cross-contamination occurred during its production.icin (a toxic substance present in the plant) does not partition into the oil because it is water-soluble, therefore, castor oil does not contain ricin, provided that no cross-contamination occurred during its production.
Best Answer: Yes. Castor oil comes from the castor bean. Food grade castor oil can be used in food additives, flavorings and as a mold inhibitor. However, it's more commonly recognized for its medicinal purposes (as a laxative, for example).eport Abuse. Yes, castor oil is inedible oil from a vegetable source (castor beans). It is a very heavy and thick oil. It is sometimes used in food but you shouldn't use it to cook with as you would vegetable oil.