What is responsible for the formation and stabilization of actin bundles and networks?

Which cellular function may be disrupted because of a malformation of the intermediate filaments?

Which of the following regions of a sarcomere at rest is characterized by the presence of myosin only? a) A band b) H zone c) I band d) Z line

Describe the interkinetic nuclear movement

What prevents the filaments from sliding back to their original position each time a myosin cross bridge detaches from actin?

13) Draw a graph representing the changes in membrane potential across the axonal membrane before, during, and after an action potential. On your graph, use a highlighter to clearly indicate for which portions of your graph the letter corresponding to each cellular event listed below belongs. List of cellular events: A) All K* channels open B) All Na* channels close C) The Na*/K* ATPase cotransporter transports Na* and K* across the membrane. D) All Na* channels open E) The threshold value of membrane potential is attained. F) All K* channels close G) Some Na* channels open Your graph:

Why is myosin II the only myosin capable of producing contractile force?

Cofilin preferentially binds to older actin filamentsand promotes their disassembly. How does cofilin distin-guish old filaments from new ones?

Describe the structure of actin and myosin, including any accessory proteins.

What is membrane potential?