You assay cell surface oligosaccharides from a blood sample. after determining the composition of the oligosaccharides relative to a reference monosaccharide, fucose, you conclude the donor is blood type b. what brought you to this conclusion?

Here the fucose is linked to galactose by alpha1,2 glycosidic linkage.

Explanation:

Fucose is a deoxy sugar consist of 6 carbon atoms which means fucose is a hexose sugar.

   Fucose does not contain -OH group at C6 carbon that"s why it is termed as deoxy sugar.

     Fucose can link to both Nactylglucosame by alpha-1,6 glycosidic linkage and to galactose by alpha-1, glycosidic linkage  generates the H antigen.

   As donor is blood type B that means fucose is linked to galactoseof H antigen by alpha 1,2glycisidic linkage.

the answer is a or when it says crossing over

producers: apple trees, potatoes, carrots, grains, acorns, cabbage, grass, corn, lettuce

consumers: deer, mice, rabbits, chickens, squirrels, horses, worms, cows

predators: eagles, frogs, wolves, owls