HS1-1 Introduction to the Musculoskeletal System

Question 1

How many components of the axial skeleton are there, and what are they?

Answer 1

four components:
skull
vertebral column
ribs
sternum

Question 2

How many components of the appendicular skeleton are there, and what are they?

Answer 2

two components:
pectoral girdle
pelvic girdle

Question 3

What is the pectoral girdle?

Answer 3

incomplete girdle that provides support for upper limbs

Question 4

What are the two major components of the pectoral girdle?

Answer 4

scapula

clavicle

Question 5

What is the pelvic girdle?

Answer 5

girdle that transmits weight of trunk to lower limbs and supports lower limbs

Question 6

What are the four major components of the pelvic girdle?

Answer 6

hip bones (pubis, ischium, ilium) and sacrum

Question 7

How does cartilage receive its nutrition?

Answer 7

through diffusion, since it is avascular

Question 8

What are the four major functions of the cartilage?

Answer 8

replaces bone when increased flexibility is needed

provides protection of bone surfaces in joints

provides support of soft tissues

enables bone growth and elongation of long bones

Question 9

To which skeleton — axial or appendicular — does the sacrum belong?

Answer 9

the sacrum is part of the axial skeleton

Question 10

What are the three types of joints?

Answer 10

fibrous

cartilaginous

synovial

Question 11

Describe fibrous joints.

Answer 11

restricted movement

Question 12

What are the two types of cartilaginous joints?

Answer 12

primary cartilaginous joints

secondary cartilaginous joints

Question 13

Describe cartilaginous joints.

Answer 13

united by hyaline cartilage or fibrocartilage

Question 14

Describe primary cartilaginous joints.

Answer 14

temporary joints seen during development

Question 15

Describe secondary cartilaginous joints.

Answer 15

strong, slightly movable joints united by fibrocartilage.

Question 16

Describe synovial joints. (2)

Answer 16

fluid-containing joint cavity

most common joint in the body

Question 17

Describe the articular capsule.

Answer 17

bones are separated by cavity but united by an articular capsule reinforced by ligaments

Question 18

Describe the synovial membrane.

Answer 18

lines the inner surface of the articular capsule and secretes synovial fluid

Question 19

What is synovial fluid?

Answer 19

viscous substance that resembles the white of an egg

Question 20

Describe the articular cartilage.

Answer 20

covers the articulating surfaces of bones within the joint capsule

Question 21

Describe ligament.

Answer 21

dense fibrous connective tissue that is generally collagenous in substance

Question 22

Define osteokinematics.

Answer 22

motion of bones relative to the 3 principal planes of the body

Question 23

Define tendon.

Answer 23

the portion of the muscle that attaches to bone

Question 24

Define isometric contraction.

Answer 24

occurs when a muscle is producing active force while maintaining a constant length

Question 25

Define concentric contraction.

Answer 25

occurs as a muscle produces active forces as it shortens

Question 26

Define eccentric contraction.

Answer 26

occurs when a muscle produces active forces as it increases in length

Question 27

What is an agonist muscle?

Answer 27

muscle that has primary responsibility for initiating desired movement

Question 28

What are synergists?

Answer 28

group of muscles sharing the same function

Question 29

What are antagonists?

Answer 29

group of muscles that have opposite function to prime mover or synergistic muscles

Question 30

What are fixators?

Answer 30

when prime movers and antagonists contract together, they behave as fixators and stabilize a joint

Question 31

What is the structural unit of a muscle?

Answer 31

muscle fiber, each of which is innervated by one motor axon

Question 32

What is the functional unit of a muscle?

Answer 32

motor unit, which consists of the motoneuron and all the muscle fibers it innervates

Question 33

Which type of muscle contraction is most likely to cause injury?

Answer 33

eccentric

Question 34

What comprises a motor unit?

Answer 34

motor neuron + muscle fiber

Question 35

What is the function of a vertebral body?

Answer 35

support weight

Question 36

What is the function of vertebral arches?

Answer 36

protection

Question 37

What comprises the vertebral arch?

Answer 37

lamina + pedicles

Question 38

What is the function of vertebral processes?

Answer 38

muscle/tendon attachment