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.
Seasons are fundamental to how we understand the climate and the environment, but for hundreds of years academics have argued that their specialist field is the one which defines official start of autumn. In meteorological terms autumn begins on September 1, as each season is defined as a three-month period. Astronomers base the date of the seasons upon celestial events, in this case the autumnal equinox, when night and day are roughly equal length.