3_Ch 8, chapter questions

Question 1

Name the proteins

Question 2

Describe these events at the neuromuscular junction:

Answer 2

1.

2.

3.

4.

Question 3

What functional joint class contains the least-mobile joints?

Answer 3

The synarthroses are the least mobile of the joint types.

Question 4

How are joint mobility and stability related?

Answer 4

In general, the more stable a joint, the less mobile it is.

Question 5

To what functional class do most fibrous joints belong?

Answer 5

Most fibrous joints are synarthroses (immobile).

Question 6

Babies are sometimes diagnoses with a condition called craniosynostosis. Using the definition you just learned, describe what you think this condition is and predict what problems it might cause.

Answer 6

Cranio- refers to the skull bones (p. 201), and synostosis refers to ossification of skull bone sutures. Craniosynostosis is a disorder in which the sutures in the skull close prematurely in babies. Premature closing of suture prevents the brain from browing normally.

Question 7

Evan is 25 years old. Would you expect to find synchonroses at the ends of his femur? Explain. (p. 187)

Answer 7

Evan would not have a synchondroses at the ends of his femur. By age 25, his epiphyseal plats have fused and become synostoses.

Question 8

How do bursae and tendon sheaths improve joint function?

Answer 8

Bursae and tendon sheaths help reduce friction during joint movement.

Question 9

Generally speaking, what factor is most important in stabilizing synovial joints?

Answer 9

The muscle tendons that cross the joint are typically the most important factor in stabilizing synovial joints.

Question 10

On the basis of movement allowed, which of the following joints are uniaxial? Hinge, condylar, saddle, pivot

Answer 10

The hinge and pivot joints are uniaxial joints.

Question 11

Name the category (according to its shape and movement allowed) of each of the synovial joints labeled a-d below (p. 264)

Answer 11

The synovial joint categories are a) ball-and-socket, b) hinge, c) pivot, and d) condylar.

Question 12

Nick bent over to pick up a dime. What movement was occurring at his hip joint, at his knees, and between his index finger and thumb?

Answer 12

Nick’s hip joint was flexed and his knees extended and his thumb was in opposition (to his index finger).

Question 13

Sketch the general structure of a synovial joint. Lavel the articular cartilages, the articular capsule, and joint cavity.

Answer 13

drawing

Question 14

Of the five joints studied in more detail – hip, shoulder, elbow, knee, and temporomandibular–which two have menisci? Which act mainly as a uniaxial hinge? Which depend mainly on muscles and their tendons for stability?

Answer 14

The knee and temporomandibular joints have menisci. The elbow and knee each act mainly as a uniaxial hinge. The shoulder depends largely on muscle tendons for stability.

Question 15

What does the term arthritis mean?

Answer 15

Arthritis means inflammation of the joint.

Question 16

What is the cause of Lyme disease?

Answer 16

Lyme disease is caused by spirochete bacteria and transmitted by a tick bite.

Question 17

From an arthritis patient’s history and physical examination, how would you determine if he or she might have OA or RA?

Answer 17

RA (rheumatoid arthritis) typically produces pain, swelling, joint deformations that tend to be bilateral and crippling. OA (osteoarthritis) patients tend to have pain, particularly on rising, which is relieved by gentle exercise, and enlarge bone ends (due to spurs) in affected joints. Affected joints may exhibit crepitus.

Question 18

Match the key terms to the appropriate descriptions:

Key: a) fibrous joints b) cartilaginous joints c) synovial joints

1) exhibit a joint cavity
2) types are sutures and syndesmoses
3) bones connected by collagen fibers
4) types include synchondroses and symphyses
5) all are diarthrotic
6) many are amphiarthrotic
7) bones connected by a disc of hyaline cartilage or fibrocartilage
8) nearly all are synarthrotic
9) shoulder, hip, jaw, and elbow joints

Answer 18

1) c
2) a
3) a
4) b
5) c
6) b
7) b
8) a
9) c

Question 19

Freely movable joints are a) synarthroses, b) diarthroses, c) amphiarthroses

Answer 19

b

Question 20

Anatomical characteristics shared by all synovial joints include all except a) articular cartilage, b) joint cavity, c) an articular capsule, d_ presence of fibrocartilage

Answer 20

d

Question 21

Factors that influence the stability of a synovial joint include a) shape of articular srufaces, b) presence of strong reinforcing ligaments, c) tone of surround muscles, d) all of these

Answer 21

d

Question 22

The description “articular surfaces deep and secure; capsule heavily reinforced by ligaments and muscle tendons; extremely stable joint” best describes a) the elbow joint, b) the hip joint, c) the knee joint, d) the shoulder joint

Answer 22

b

Question 23

Ankylosis means a) twisting of the ankle, b) tearing of ligaments, c) displacement of a bone, d) immobility of a joint due to fusion of its articular surfaces.

Answer 23

d

Answer 24

d

Question 25

Define joint

Answer 25

Joints are defined as sites where two or more bones meet.

Question 26

Joint movements may be nonaxial, uniaxial, or multiaxial. Define what heach of these terms means.

Answer 26

NONAXIAL movements are gliding or slipping movements only; UNIAXIAL movements are in one plane; BIAXIAL movements are in two planes; and MULTIAXIAL movements are in or around all three planes or axes.

Question 27

Name two types of uniaxial, biaxial, and multiaxial joints.

Answer 27

Unixial joints include hinge (elbow) and pivot (atlantoaxial and radioulnar) joints. Biaxial joints include condylar (knuckle) and saddle (thumb) joints. Multiaxial joints are ball-and-socket joints (hip and hsoulder).

Question 28

Why are sprains and cartilage injuries a particular problem?

Answer 28

Sprains and cartilage injuries are particularly problematic because cartilage and ligaments are poorly vascularized and tend to heal very slowly.