Chapter 10 Homework

Calcium ions are released from the sarcoplasmic reticulum into the cytosol

at the beginning of a contraction.

Skeletal muscle contraction will continue to occur as long as the following chemicals are available in the cytosol of the muscle fiber.

calcium ions and ATP

Release of calcium from these structures triggers skeletal muscle contraction.

terminal cisterns of sarcoplasmic reticulum

What energizes the myosin head?

ATP hydrolysis reaction

What type of tendon is formed when the connective tissue elements of a skeletal muscle extend as a broad flat layer?

Aponeurosis

Which of the following correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction?

Axon of neuron, sarcolemma, T tubules

Which of the following regions of a sarcomere contain thin filaments?

Both I band and A band.

This is the outermost layer of connective tissue surrounding a skeletal muscle.

Epimysium

Which property of muscle gives it the ability to stretch without damage?

Extensibility

In an isometric contraction the muscle develops tension but does not

Lengthen

During muscle contraction by the sliding filament mechanism, thin filaments are pulled towards the

M Line

Which of the following consists of a somatic motor neuron and all the skeletal muscle fibers it stimulates?

Motor Unit

The contractile organelles of a skeletal muscle fiber are thread-like structures called

Myofibrils

Which of the following is NOT a major function of muscle tissue?

Production of vitamins.

What regulatory proteins can be found in the thin filaments of skeletal muscle fibers?

Tropomyosin and troponin

Myofibrils contain

contractile proteins. regulatory proteins. structural proteins.

Which of the following is a common effect of aging on skeletal muscle?

loss of muscle mass decrease in maximal strength a slowing of muscle reflexes loss of flexibility

The different types of muscle tissue differ from each other by

microscopic anatomy. location. type of Control. both microscopic anatomy and location

Cross bridges are formed during muscle contraction when _____ on the thick filaments binds to _____ on the thin filaments.

myosin; actin

This is the least powerful type of skeletal muscle fiber.

slow oxidative fiber