chapter 10 skeletal muscle

Place the organizational level of muscle tissue in order, beginning with the entire muscle and ending with the smallest component.

1. Muscle 2. Fascicle 3. Muscle fiber 4. Myofibril 5. Myofilament

The area of the muscle fiber where the actin and myosin myofilaments overlap is the

A band.

Check all that are a function of skeletal muscle tissue.

Body movement Maintenance of posture Heat production Regulating elimination of materials Protection and support

Which connective tissue wrapping separates individual muscle fibers?

Endomysium

Match each structure with the connective tissue layer that surrounds it.

Epimysium = Muscle Perimysium = Fascicle Endomysium = Muscle cell

During contraction, the actin myofilaments slide toward the

H zone.

Myofilaments within myofibrils are arranged in repeating microscopic cylindrical units called ____________.

Sarcomeres

Match each sarcomere region with the filament(s) it contains.

Thick Filaments = H band, M line Thin Filaments = I band Both Thick and Thin Filaments = A band

Myofibrils are composed of protein filaments called actin and myosin.

True

Check all that are proteins of thin filaments.

actin, troponin, tropomyosin

The axon of a motor neuron travels through the epimysium and perimysium and enters the _________, where it delivers a nerve impulse to an individual ________.

endomysium; muscle fiber

A skeletal muscle fiber (cell) contains a single nucleus.

false

In a relaxed muscle, the ends of the actin filaments overlap.

false

In fully contracted muscles, the actin filaments lie side-by-side.

false

A bundle of muscle fibers is known as a

fascicle

An extensive network of blood vessels and nerve fibers extends through both the epimysium and the _____ of a muscle.

perimysium

The muscle cell membrane is called the

sarcolemma

The distance from one Z disk to the next Z disk is called a(n)

sarcomere.

At the ends of muscles, the connective tissues merge to form a __________, which attaches the muscle to other structures.

tendon

The component of a muscle fiber that quickly transports a muscle impulse from the sarcolemma throughout the entire muscle fiber is called the

transverse tubule (T-tubule).

Which is a characteristic of skeletal muscle from the selections below?

Multinucleated