Which process must occur for a muscle to be able to relax? A.
The concentration of calcium in the myofibril must decrease.
B.
Myosin and actin must attach to each other.
C.
A nerve must initiate an action potential in the muscle fiber.
D.
The amount of ATP in the neuromuscular junction must increase.

Scientists are conducting a study on the effectiveness of a new drug on memory loss. they are giving some of the test subjects the new drug to find out if it improves their long-term memory. which are possible limitations of this study? check all that apply. a) test subjects may want to participate in additional experiments. b) test subjects may think they should be paid more. c) test subjects may get bored and want to quit early. d) test subjects may have to travel during the experiment. e) test subjects may have full-time jobs. this is multiple choice. you for the !