People with sickle cell anemia have one incorrect amino acid in their beta chain. the first seven amino acids in the beta chain for hemoglobin a (normal) and hemoglobin s (sickle cell) are listed below. which amino acid is different in hemoglobin s?

Valine

Explanation:

hemoglobin A (normal) is HbA, while hemoglobin S (present in people with sickle cell anemia) is HbS

A sequence of 146 amino acids is present in the Hemoglobin.

The first 6 amino acids in HbA are: valine, histidine, leucine, threonine, proline, and glutamic acid.

The first six amino acids in HbS is:

valine, histidine, leucine, threonine, proline, and VALINE

In Hbs, the 6th amino acid (Glutamic acid) has already been mutated to Valine, a nonpolar, branched amino acid.

the answer to your question is b

lizards have adapted to life in the desert. some desert lizards have toes with spiny scales to them run across the sand without sinking. some use the sand to hide from predators, or to search for small animals that they prey upon.