The mutation resulting in sickle cell disease changes one base pair of dna so that a codon now codes for a different amino acid

Missense mutation

Explanation:

In sickle cell the glutamic acid in the 6th position of the beta chain of HbA (normal haemoglobin) is change to valine in HbS (sickle cell haemoglobin). This occur when there's a single nucleotide mutation. The (A) nucleotide in the condon (GAG) of glutamic acid is substituted for a (T) nucleotide. This single nucleotide substitution converts a glutamic acid codon (GAG) to a valine codon (GTG), which leads to polymerization of haemoglobin molecules in red blood cells. This cause a distortion of cell to a sickle shape.

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

answer:   option a) glucagon was secreted by his pancreas before he ate the cookies because blood glucose was low. insulin was secreted after he ate the cookies because his blood glucose was high.

explanation: