During the labs in this class, the actions of the hamstrings and quadriceps muscle groups were often analyzed. Think about knee flexion in the following three scenarios:

Sitting on the edge of a table with knee in full extension, then flex your knee to approximately 90 degrees of flexion.
Lie prone on a table with your leg straight, then flex your knee to approximately 90 degrees.
Stand upright, then squat and flex your knee to approximately 90 degrees.
Which functional muscle group and what type of contraction is working/taking place in each of the above 3 situations. Explain, in detail, why there are differences in each scenario. This is a 10 point question, so be sure to discuss each scenario individually, as well as comparing their similarities and/or differences.