In humans, the DMD gene is required for proper muscle function. Mutations in the DMD gene display X-linked recessive inheritance that leads to muscular dystrophy. The DMD gene has enhancers that are required for gene expression in specific muscles of the body. enh1 is required for expression in the heart; enh2 is required for expression in the arm muscles; enh3 is required for expression in the leg muscles. For an individual with the genotype listed below, what phenotype would you expect

Explanation:

As the inheritance is X-linked,recesson so for expression of muscular dystrophy in any given muscle,

enh1+ /enh1 + = Shows muscular dystrophy in heart (Homozygous for -)

enh2+/enh2+ = Shows no muscular dystrophy in arms (Homozygous for +)

enh3-/enh3+ = variabl or mosaic for muscular dystrophy in leg muscles (Hetrozygous for enh3)

the cell theory states that all living things including animals, as well as plants, are made of cells.

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.