Exam Three Questions

Question 1

What are the four steps of muscle contraction?

Answer 1

1. ATP binds to myosin head, causing dissociation from actin.
2. Tightly bound ATP is hydrolyzed, and conformational changes occur. ADP and Pi remain associated with myosin head.
3. Myosin head attaches to actin filament, causing release of Pi.
4. Pi release triggers a “power stroke”, a conformation change in the myosin head that moves actin and myosin filaments relative to one another. ADP is released in the process.

Question 2

How do you figure out kD value from a graph?

Answer 2

kD value = [Ligand] at 0.5 theta, which is the 0.5 on the y-axis, compared to location of Ligand, which is on x-axis.

Question 3

What is the nonreducing end of a starch?

Answer 3

The nonreducing end of a starch is what gets enzymatically cleaved to release glucose monomeric units.

Question 4

What are the proteins inside and outside of the membrane?

Answer 4

Inside- Integral protein
Outside- Peripheral protein