What are the threadlike proteins that attach to platelets in blood clotting?

fibrin

Explanation:

Fibrin is a protein that acts as a first response whenever your body is injured in order to play an important role in the blood clotting process. When any type of injury that causes blood leakage occurs and coagulation begins, an alert is then sent to the body to start producing fibrin.

In the form of long strands, each fibrin molecule intertwines to form a thin mesh around the lesion. As a result, this mesh stops the blood by capturing red blood cells, leukocytes and platelets, generating a clot and forming a kind of tampon at the injured site.

In summary, we can say that fibrin is a yarn-like protein that binds to platelets in blood clotting.

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.