What would happen if you accidentally ingested a toxin that completely inhibited the function of the Ca2+ pumps in the sarcoplasmic reticulum membrane?

Please fill in the blanks: 21) the binding of ______________ to troponin removes troponin from ____________ on thin filaments to expose myosin binding sites 22) the energy released from the splitting of __________________ causes myosin cross bridges to pivot inward to pull the thin filaments inward toward the H zone

Choose the best description of how myosin and actin are arranged within the two types of protein filaments in myofibrils. a.) Actin makes up the think filaments, and myosin makes up the thin filaments. b.) Myosin makes up the think filaments, and actin makes up the thin filaments. c.) Myosin and actin are randomly interspersed in the think filaments but are absent from the thin filaments. d.) Myosin and actin overlap with each other to make up both the think and thin filaments.

Which of the following regions of a sarcomere at rest is characterized by the presence of myosin only? a) A band b) H zone c) I band d) Z line