The synaptic vesicles contain… a.Acetylcholine b.Calcium ions c.Myoglobin d.actin
The process by which a motor neuron releases acetylcholine is a.Exocytosis b.Simple diffusion c.Active transport d.filtration
What structures meet at the neuromuscular junction? a.T-tubules and the sarcoplasmic reticulum b.The sarcolemma and the T- tubules c.The axon of the motor neuron and the sarcolemma d.The axon of the motor neuron and myosin
Creatine phosphate serves to a.Cause the decomposition of ATP b.Cause the decomposition of ADP c.Supply energy for the synthesis of ATP d.Supply energy for the change of ATP to ADP
The all-or-none response means… a.All the muscles in a region contract together b.All of the muscle fibers/cells within a muscle contract together c.When a muscle fiber contracts, it contracts completely
Rigor mortis occurs because of a.Excessive ATP, which prevents muscle relaxation b.Lack of ATP, which prevents muscle relaxation (no ATP to release crossbridge between actin & myosin) c.Excessive ATP which causes muscle contraction
The botulinus toxin that causes botulism acts by a.Preventing the release of acetylcholine b.Promoting the release of acetylcholine c.Causing acetylcholine to be decomposed d.Preventing the decomposition of acetylcholine
Smooth muscle is found a.Attached to bones b.Lining hollow organs and tubes c.In the wall of the heart
Muscle tissue that is striated and involuntary a.Skeletal b.Smooth c.Cardiac d.Both cardiac and smooth
A muscle cramp is likely due to a lack of a.Actin b.Myosin c.ATP d.ADP
Which of the following is the smallest a.Myofilament b.Myofibril c.Myofiber d.fascicle Myofibril is the organelle within the muscle cell/fiber and the myofilaments (actin & myosin) are the proteins within the myofibril.
Multiunit smooth muscle a.Is composed of sheets of muscle cells b.Tends to display rhythmicity c.Occurs in the walls of the stomach and intestines d.None of these a, b, & c are all characteristics of visceral smooth muscle.
Striations are seen in… a.Osseous tissue b.Smooth muscle c.Skeletal muscle cells d.Tendons and ligaments
Myoglobin… a.Stores oxygen in the muscle tissue b.Binds to actin to shorten the myofibrils c.Stores ATP d.Separates one sarcomere from another
Connective tissue that separates the fascicles in skeletal muscle is called the a.Epimysium b.Endomysium c.Perimysium
Connective components of muscle organ Fascicle Epimysium Perimysium Endomysium Muscle fiber
The sarcolemma is the a.Storage site for calcium b.Cell membrane of a myofiber c.Cytoplasm of myofiber
The function of the intercalated disks in cardiac muscle tissue is to a.Separate one sarcomere from another b.Store ATP c.Slow the rate at which calcium ions are returned to the sarcoplasmic reticulum d.Provide a mechanism by which all of the cells in a network can contract as a functional unit
The sliding filament theory states that when a muscle fiber shortens… a.Actin filaments become shorter when they combine with myosin b.Thin myofilaments are pulled toward the center of the sarcomere c.Myosin heads rotate when they attach to actin, causing them to fold.
The function of calcium ions in skeletal muscle cell contraction is to a.Bind to receptors on the sarcolemma b.Bind to oxygen; for cellular respiration c.Bind to the thin myofilament (actin) changing its shape so that the thick myofilament (myosin) can bind.
Skeletal muscles are stimulated to contract when… a.Calcium ions bind to the sarcolemma b.Acetylcholine binds to receptors on the sarcolemma, causing the stimulus to spread through out the muscle cell c.ATP is released from the sarcoplasmic reticulum d.Oxygen binds to the hemoglobin
Sarcomeres are separated from one another by a.I bands b.H zone c.A bands d.Z lines
The region of the sarcomere that contains thin myofilaments, but not thick myofilaments is the a.A band b.I band c.Z line d.T-tubule