Musculoskeletal System (Pearson MyLab & Mastering A&P)

Question 1

Which of the following is NOT a distinguishing feature of a synovial joint?

• a capsule that creates a space in the joint
• ligaments connecting the two bones of the joint
• hyaline cartilage connecting the two bones of the joint
• synovial fluid

Answer 1

hyaline cartilage connecting the two bones of the joint

Rationale: Hyaline cartilage makes up the articular cartilage in a synovial joint, but this does not connect the two sides together.

Question 2

The quadriceps femoris is composed of three “vastus” muscles and the _______.

• semitendinosus
• biceps femoris
• rectus femoris
• semimembranosus

Answer 2

rectus femoris

Question 3

Which of the following is a hamstring muscle?

• vasts lateralis
• vasts medialis
• rectus femoris
• biceps femoris

Answer 3

biceps femoris

Rationale: The hamstrings are fleshy muscles of the posterior thigh (biceps femoris, semitendinosus, and semimembranosus). They cross both the hip and knee joints and are prime movers of thigh extension and knee flexion.

Question 4

The pelvic girdle does NOT include the ________.

• pubis
• ilium
• ischium
• femur

Answer 4

femur

Question 5

Which joints are correctly matched?

• elbow; pivot
• interphalangeal; plane
• wrist; saddle
• ankle; hinge

Answer 5

ankle; hinge

Question 6

The arrows in B and C point to structures that can both be described as ________.

• ligaments
• tendons
• muscles
• bones

Answer 6

ligaments

Rationale: The band of fibrous tissue that connects two bones is generally referred to as a ligament. In the case of the gomphosis shown in C, the fibrous connection is specifically termed the periodontal ligament.

Question 7

Which of the following represents a structural classification for joints that are separated by a joint cavity?

• fibrous
• diarthrosis
• synovial
• cartilaginous

Answer 7

synovial

Rationale: Synovial is a structural classification for joints. Structural classification focuses on the material binding the bones together and whether a joint cavity is present.

Question 8

Which of the following terms describes the range of movement of the illustrated joint?

• diarthrotic
• synarthrotic
• synovial
• amphiarthrotic

Answer 8

diarthrotic

Rationale: Synovial joints are considered to be freely movable and are therefore described as diarthrotic.

Question 9

The contractile units of skeletal muscles are _______.

• microtubules
• T tubules
• myofibrils
• mitochondria

Answer 9

myofibrils

Question 10

On the basis of structural classification, which is a fibrous joint?

• symphysis
• syndesmosis
• pivot
• synchondrosis

Answer 10

syndesmosis

Question 11

Saddle joints have concave and convex surfaces. Identify a saddle joint of the skeleton.

• interphalangeal joint of the finger
• metacarpophalangeal joint of the finger
• carpometacarpal joint of the phalanges
• carpometacarpal joint of the thumb

Answer 11

carpometacarpal joint of the thumb

Question 11

Saddle joints have concave and convex surfaces. Identify a saddle joint of the skeleton.

• interphalangeal joint of the finger
• metacarpophalangeal joint of the finger
• carpometacarpal joint of the phalanges
• carpometacarpal joint of the thumb

Answer 11

carpometacarpal joint of the thumb

Question 12

Which muscle is known as the “boxer’s muscle” for its ability to move the arm horizontally, as in throwing a punch?

• A
• B
• C
• D

Answer 12

• D

Rationale: The serratus anterior can be used to violently pull the scapula laterally and thus pull the shoulder forward, adding strength to a horizontal punch.

Question 13

Which of the following is NOT a member of the hamstrings?

• gracilis
• biceps femoris
• semitendinosus
• semimembranosus

Answer 13

gracilis

Question 14

Which muscle(s) is (are) contracted to exhale forcibly?

• internal intercostals and rectus abdominus
• rectus abdominis and diaphragm
• external intercostals and diaphragm
• diaphragm alone

Answer 14

external intercostals and diaphragm

Question 15

What is the structural unit of compact bone?

• canaliculus
• osteoid
• osteon
• Haversian canal

Answer 15

osteon

Rationale: The structural unit of compact bone is the osteon, an elongated cylinder oriented parallel to the long axis of the bone.

Question 16

Paralysis of which of the following muscles would make an individual unable to flex the knee?

• brachioradialis
• gluteal muscles
• hamstring muscles
• soleus

Answer 16

hamstring muscles

Question 17

The smallest contractile unit within skeletal muscle would correspond to the distance between which two points in the figure?

• 1 and 3
• 2 and 6
• 3 and 5
• 1 and 7

Answer 17

1 and 7

Rationale: The distance between points 1 and 7 spans a sarcomere, the smallest contractile unit of a muscle fiber.

Question 18

Which of the following statements is correct?

• If a joint can exhibit adduction and abduction, then it is biaxial.
• A joint that exhibits adduction and extension is uniaxial.
• If a joint can exhibit extension, abduction, and rotation, then it is triaxial.
• If a joint can exhibit flexion, extension, and abduction, then it is triaxial.

Answer 18

If a joint can exhibit extension, abduction, and rotation, then it is triaxial.

Rationale: A joint that moves in these three directions is triaxial. The three directions in this example are extension/flexion, abduction/adduction, and rotation.

Question 19

The cell responsible for secreting the matrix of bone is the ________.

• osteoclast
• chondrocyte
• osteoblast
• osteocyte

Answer 19

osteoblast

Question 20

Based upon structural classification, what type of joint is a suture?

• synarthrotic joint
• fibrous joint
• amphiarthrotic joint
• cartilaginous joint

Answer 20

fibrous joint

Rationale: Sutures are classified structurally as fibrous joints. They would be classified functionally as synarthrotic joints based upon their degree of movement.