Crossing over occurs when a.) sister chromatids are pulled apart at the centromere during anaphase ii. b.) homologous chromosomes join together to form tetrads during prophase i. c.) chromosomes are grouped together into new nuclei during telophase ii.                  d.) tetrads of homologous chromosomes randomly line up in metaphase i.

answer; /// i believe that the correct answer is ( monophasic ); ethinyl estradiol- ethynodiol diacetate is a monophasic oral contraceptive agent; ///

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.