Ivy Tech APHY 101 Muscle System Practice Test 2026 – Comprehensive All-in-One Guide for Exam Success!

Unlock all questions

This demo includes only 20 questions. Upgrade to access hundreds of questions, flashcards, exam simulations, and disable ads.

Full question bankExam simulationsFlashcards
From $9.99Unlock all
Session length

1 / 20

During the cross‑bridge cycle, what describes the power stroke?

The myosin head pivots, pulling the actin toward the center of the sarcomere

The power stroke is the lever-arm motion of the myosin head as it pivots while bound to actin, pulling the actin filament toward the center of the sarcomere. This rotation converts the chemical energy stored in the cocked myosin head (from ATP hydrolysis) into mechanical work, shortening the sarcomere. It happens after the myosin head forms a cross-bridge with actin and releases Pi, setting the stage for sliding the thin filament. ATP binding later causes the myosin head to detach and reset for another cycle.

The myosin head detaches from actin

Calcium binds to troponin

ATP is hydrolyzed to cock the head

Next Question
Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy