Motor Physiology

Question 0

Stabilizes sarcolemme & prevents contraction-induced rupture

Answer 0

Dystrophin

Question 1

Tethers myosin to Z lines (scaffholding), binds Z lines to M line

Answer 1

Titin

Question 2

Binds actin to Z lines

Answer 2

Actinin, Cap2 protein

Question 3

Binds Z lines to sarcolemma

Answer 3

Desmin

Question 4

Act as a molecular ruler that sets the length of actin during assembly

Answer 4

Nebulin

Question 5

What is the distance achieved in each cross-bridge cycle?

Answer 5

10 nanometers

Question 6

Small motor units are recruited first before big motor units

Answer 6

Size principle

Question 7

Multiple fiber summation

Answer 7

Spatial summation

Question 8

Frequency summation

Answer 8

Temporal summation

Question 9

Each contraction occurs after complete relaxation producing stronger contraction each time

Answer 9

Staircase (Treppe) effect

Question 10

Basis for treppe effect

Answer 10

Ca2 accumulation, pH changes, increased temperature

Question 11

Complete fusion of individual muscle contraction when Ca is all used up

Answer 11

Tetany