Human blood may contain either or both of two antigens, a and b. blood that contains only the a antigen is called type a, blood that contains only the b antigen is called type b, blood that contains both antigens is called type ab, and blood that contains neither antigen is called type o. at a certain blood bank, 28% of the blood donors have type a blood, 15% have type b, and 10% have type ab. round the answers to two decimal places.

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

Which u.s. state lists the horned toad as its state reptile?

The diagram below shows the layers of a rock having a trilobite: a rock column labeled rock is shown. the column has three layers. the bottommost layer of the rock has one shaded rhomboid shape, the middle layer has a rhombus with a diagonal along with two identical organisms marked as, trilobite, in the key, the top layer has two semicircles. a key is shown on the right side of the diagram. the shaded rhombus is marked as a, the rhombus with the diagonal is marked as b, the semicircle is marked as c which statement about the rock fossils is true?