Best Answer: Your genotype determines your blood type before your born. There are three alleles or versions of the blood type gene: A, B, and O. Since everybody has two copies of these genes, there are six possible combinations; AA, BB, OO, AB, AO, and BO.h is not passed down from parents. With your parents having AB and O, you can only have type A or type B blood because O is recessive. You could have type O if your mother was AO or BO, but she isn't. Since you have type A, your blood is AO (A from your mother and O from your father... but A is dominant).
Rating Newest Oldest. Best Answer: Officially, the third week of September when Fall starts all over the U.S at the autumnal equinox - this year it is September 22nd. And you can find this answer easily through many other methods, like simply googling when does fall start.. You'd be surprised how google search can answer questions.
Report Abuse. 1  Mr Weather's quite thorough but only half correct - only for the northern hemisphere. 2  This Site Might Help You. 3  When Does Summer End.  Spring Starts-March 1  21st. What Day Does Fall Start.  winter begins officially dec. 21 and then go 3 months after for each of the rest of the seasons...march 21, etc. iprfm Â· 9 years ago.