You Are Holding a Small Textbook in Your Hand, and You

Multiple Choice

You are holding a small textbook in your hand, and you begin to flex your elbow to raise the book. You stop with your elbow flexed at about 90 degrees, and the book held out in front of you. What is occurring in your biceps muscle at this time?

A) your biceps is in a state of unfused tetanus
B) your biceps is latched
C) Ca²⁺ is elevated in biceps muscle fibers
D) both your biceps is in a state of unfused tetanus AND Ca²⁺ is elevated in biceps muscle fibers
E) both your biceps is latched AND Ca²⁺ is elevated in biceps muscle fibers