Chapter 09: Muscular System Herlihy: The Human Body in Health and Illness, 7th Edition

Which of the following functions do the muscles NOT perform?

c. They lower blood pressure.

Each muscle fiber is composed of long cylindrical structures called:

a. myofibrils.

Which of the following muscles is described as striated and involuntary?

d. Cardiac

Shivering occurs when skeletal muscle contracts in an attempt to restore normal body temperature. Inte

d. all are correct.

Actin is:

b. a contractile protein that is part of the thin filament.

Which of the following forms cross-bridges with actin?

c. Myosin

"Pumping iron" is most likely to cause:

c. hypertrophy.

Which of the following is not a facial muscle?

c. Sternocleidomastoid

Which muscle is located on the posterior area of the body?

a. Latissimus dorsi

Which group of muscles is located on the posterior thigh?

c. Hamstrings

The biceps femoris, semitendinosus, and semimembranosus:

c. are the hamstrings.

The rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius:

d. are the muscles of the quadriceps femoris.

The quadriceps femoris group and the hamstrings:

c. lie along the thigh.

Which flat muscle covers the forehead and raises the eyebrows (for a "surprised" look)?

a. Frontalis

Which muscle is located in the lower extremities?

a. Peroneus longus

Which group of muscles moves the arm at the shoulder?

c. Rotator cuff muscles

The brachialis and brachioradialis:

a. flex the forearm at the elbow.

Which large muscle or muscle group extends the thigh at the hip?

b. Hamstring

Which muscle attaches to the cranial aponeurosis and wrinkles the forehead?

a. Frontalis

"Make like a scarecrow" by contracting which muscle?

d. Deltoid

Which muscle lies along the anterior surface of the humerus and acts synergistically with the brachialis the forearm at the elbow?

c. Biceps brachii

Which structure is an extension of the sarcolemma or cell membrane, which penetrates the interior of the electrical signal to the deepest part of the muscle?

b. T tubule

The sarcoplasmic reticulum:

c. envelops the sarcomere-containing myofibrils.

What is the site of calcium storage in a relaxed skeletal muscle?

d. Sarcoplasmic reticulum

Acetylcholine is released from the neuron's membrane in response to the:

a. nerve impulse.

Which of the following is responsible for muscle relaxation?

c. . Calcium is pumped back into the sarcoplasmic reticulum.

Which of the following describes a muscle that remains in a contracted state?

b. Tetany

Which muscle separates the thoracic and abdominal cavities and is also the chief breathing muscle?

d. Diaphragm