A&P Exam 3 Study Guide Ch 10

As Mario listened to Brent's account of how he flirted with his neighbor, he raised his eyebrows and then winked at Sarah. What facial muscles was he using?

Mario was using the frontal belly of his epicranius to raise his eyebrows and the orbicularis oculi muscles to wink at Sarah.

Making Connections Table 10.14 shows that many muscles cross the knee. In addition to providing movement, these muscles perform another important function (as described in Chapter 8. What is that function?

The muscles that cross the knee also reinforce the joint by providing increased stability.

Which of the thenar muscles does not have an insertion on bones of the thumb?

The opponens pollicis does not have an insertion on the bones of the thumb.

Match the muscle names in column B to the facial muscles described in column A. Column A Column B (1) squints the eyes (2) raises the eyebrows (3) smiling muscle (4) puckers the lips (5) pulls the scalp posteriorly (a) corrugator supercilii (b) depressor anguli oris (c) frontal belly of epicranius (d) occipital belly of epicranius (e) orbicularis oculi (f) orbicularis oris (g) zygomaticus

1;C, 2;C, 3;,G, 4;F, 5;D

The prime mover of hip extension against resistance is the (a) gluteus maximus, (b) gluteus medius, (c) biceps femoris, (d) semimembranosus.

A

The prime mover of inspiration is the (a) diaphragm, (b) internal intercostals, (c) external intercostals, (d) abdominal wall muscles.

A

Which of the following is a large, deep muscle that protracts the scapula during punching? (a) serratus anterior, (b) rhomboids, (c) levator scapulae, (d) subscapularis.

A

What benefit is provided by a lever that operates at a mechanical advantage?

A lever that operates at a mechanical advantage allows the muscle to exert less force than the load being moved.

Which criterion (or criteria) is/are used in naming the gluteus medius? (a) relative size, (b) muscle location, (c) muscle shape, (d) action, (e) number of origins.

A;B

A prime mover of hip flexion is the (a) rectus femoris, (b) iliopsoas, (c) vastus muscles, (d) gluteus maximus.

B

Several muscles act to move and/or stabilize the scapula. Which of the following are small rectangular muscles that square the shoulders as they act together to retract the scapula? (a) levator scapulae, (b) rhomboids, (c) serratus anterior, (d) trapezius.

B

A muscle that assists an agonist by causing a like movement or by stabilizing a joint over which an agonist acts is a(n) (a) antagonist, (b) prime mover, (c) synergist, (d) agonist.

C

Intrinsic muscles of the back that promote extension of the spine (or head) include all but (a) splenius muscles, (b) semispinalis muscles, (c) scalene muscles, (d) erector spinae.

C

Muscles that cause plantar flexion include all but the (a) gastrocnemius, (b) soleus, (c) tibialis anterior, (d) tibialis posterior, (e) fibularis muscles.

C

Muscles that depress the hyoid bone and larynx include all but the (a) sternohyoid, (b) omohyoid, (c) geniohyoid, (d) sternothyroid.

C

The arm muscle that both flexes the elbow and supinates the forearm is the (a) brachialis, (b) brachioradialis, (c) biceps brachii, (d) triceps brachii.

C

The arrangement of muscle fibers in which the fibers are arranged at an angle to a central longitudinal tendon is (a) circular, (b) longitudinal, (c) pennate, (d) parallel.

C

In walking, which two lower limb muscles keep the forward-swinging foot from dragging on the ground? (a) pronator teres and popliteus, (b) flexor digitorum longus and popliteus, (c) adductor longus and abductor digiti minimi in foot, (d) gluteus medius and tibialis anterior.

D

The chewing muscles that protract the mandible and produce side-to-side grinding movements are the (a) buccinators, (b) masseters, (c) temporalis, (d) pterygoids.

D

The quadriceps include all but (a) vastus lateralis, (b) vastus intermedius, (c) vastus medialis, (d) biceps femoris, (e) rectus femoris.

D

Of the muscles illustrated in Figure 10.1, which could shorten most? Which two would likely be most powerful? Why?

Of the muscles illustrated in Figure 10.1, the one with the parallel arrangement (sartorius) could shorten to the greatest degree. The stocky bipennate (rectus femoris) and multipennate (deltoid) muscles would be most powerful because they pack in the most fibers.

How can the deltoid muscles both extend and flex the arm? Aren't these antagonistic movements?

The deltoid has a broad origin. When only its anterior fibers contract, it flexes and medially rotates the arm. When only its posterior fibers contract, it extends and laterally rotates the arm.

What criteria are used in naming each of the following muscles? Iliacus, adductor brevis, quadriceps femoris.

The iliacus overlies the iliac bone; the adductor brevis is a small (size) muscle that adducts (movement caused) the thigh; and the quadriceps (4 heads) femoris muscle follows the course of the femur.

The term "prime mover" is used in the business world to indicate people that get things done—the movers and shakers. What is its physiological meaning?

The term "prime mover" refers to the muscle that bears the most responsibility for causing a particular movement.

Which of the three lever systems involved in muscle mechanics would be the fastest lever—first-, second-, or third-class?

Third-class levers are the fastest levers.

What muscles would you contract to make a "sad clown's face"?

To make a sad clown's face you would contract your platysma, depressor anguli oris, and depressor labii inferioris muscles.