The cross bridge cycle starts when a Ca2 from the sarcoplasm

The cross bridge cycle starts when------.

a. Ca2+ from the sarcoplasmic reticulum binds to tropomyosin

b. Ca2+ is actively transported into the sarcoplasmic reticulum

c acetylcholine diffuses away from the synaptic cleft

d. ATP binds to troponin and is hydrolyzed to ADP and P

e. Ca2+ from the sarcoplasmic reticulum binds to troponin

Solution

Answer:

d. ATP binds to troponin and is hydrolyzed to ADP and P

Explanation:

The cocking of the myosin head - ATP is spilt by hydrolysis into ADP an Pi which releases engery. High engery myosin - if calcium is present the cycle will start over