Which of the following accurately describes the way in which a muscle moves? a. no atp is needed is the contraction of a muscle. b. during contraction, cross-bridges pull the myosin to the center of the sarcomere. c. interaction and attachment between myosin and actin cause a muscle fiber to relax. d. when actin filaments are pulled toward the center of the sacomere, the fiber shortens.

a researcher conducts an experiment on the secretion of a particular hormone in mice. scientists inject mice with a substance that stimulates the production of the hormone. the scientists then test the levels of hormones produced by the mice. the tool used to measure the hormones consistently detects the levels at 10 points lower than the actual hormone levels in the mice. this tool makes measurements, but the measurements aren't .

explanation:

no u