Hemoglobin is a complex protein that contains four polypeptide chains. the normal hemoglobin found in adults, called adult hemoglobin, consists of two alpha and two beta polypeptide chains, which are encoded by different loci. sickle-cell hemoglobin, which causes sickle-coil anemia, arises from a single mutation in the beta chain of adult hemoglobin. adult hemoglobin and sickle-cell hemoglobin differ in a single amino add. the sixth amino acid from one end in adult hemoglobin is glutamic acid, whereas sickle-cell hemoglobin has valine at this position. after consulting a codon table, indicate the mutant codons that could give rise to sickle-cell anemia. guc gaa gug gua gag

Aresearcher designed an investigation to test what effect eating different types of food would have on blood insulin levels. she selected 10 male subjects who were all 25 years of age and in good health. the experiment took place over 3 days. at 8: 00 a.m. on each day, the subjects ate a meal consisting of only 1 type of food. they had their blood insulin levels measured after consuming the meal. on day 1 they ate a high fat diet, on day 2 they ate a high protein diet, and on day 3 they ate a high sugar diel what is the independent variable in this experiment? a the age of the subjects b the blood insulin level c the type of food consumed d the time of day the meal was consumed