The Musculoskeletal System

Question 1

What makes up the skeletal system?

Answer 1

Entirety of the bones and their cartilage

Question 2

Bone is an organ compared of what different tissues?

Answer 2

Bone (osseous) tissue
Epithelium
Adipose tissue
Nervous tissue
Dense connective tissue

Question 3

Functions of the Skeletal System

Answer 3

Support by providing a structural framework for the body

Protection of many internal organs from injury

Assistance in movement by providing skeletal muscle attachments

Mineral homeostasis, bone tissue stores several minerals, especially calcium and phosphorus

Blood cell production within certain bones and connective tissues called red bone marrow produces red blood cells, white blood cells, and platelets

Triglyceride storage yellow bone marrow consists mainly of adipose cells, which store triglycerides

Question 4

Types of Bones

Answer 4

Long, short, flat, irregular

Question 5

Long bones

Answer 5

greater length than width and consist of a shaft and a variable number of ends

Femur, Tibia and Fibula, Humorous

Question 6

Short Bones

Answer 6

somewhat cube-shaped and nearly equal in length and width

Most wrist and ankle bones, Trapezoid

Question 7

Flat Bones

Answer 7

generally thin, afford considerable protection, and provide extensive surfaces for muscle attachment

Sternum, Scapulae

Question 8

Irregular Bone

Answer 8

complex shapes and cannot be grouped into any of the previous categories

Vertebrae, some facial bones

Question 9

Structure of Bone

Answer 9

Diaphysis: bone’s shaft or body

Epiphysis: distal and proximal ends of the bone

Metaphysis: regions where the diaphysis joins the epiphyses

Articular Cartilage: thin layer of hyaline cartilage covering the regions of the epiphyses where the bone articulates with other bones

Periosteum: sheath of dense irregular connective tissue and blood vessels that surround the parts of the bone outside of the articular cartilage

Medullary cavity: hollow space within the diaphysis that contain fatty yellow bone marrow

Endosteum: thin membrane that lines the medullary cavity

Question 10

What is Bone tissue made up of

Answer 10

abundant extracellular matrix (25% water, 25% collagen fibres, and 50% crystallised mineral salts)

4 types of cells:
Osteoprogenitor cells: stem cells that develop into osteoblasts

Osteoblasts: synthesise and secrete the extracellular matrix that calcifies into “bone”

Osteocytes: most numerous cells in bone tissue and they maintain bone tissues

Osteoclasts: break down extracellular matrix to release nutrients, help bones grow, and heal

Question 11

What is another word for Bone formation

Answer 11

Ossification

Question 12

Ossification occurs in what 4 principal situations?

Answer 12

1. Initial formation of bones in an embryo and fetus

2.Growth of bones during infancy, childhood, and adolescence until their adult sizes are reached

3. The remodelling of bone (replacement of old bone tissue by new bone tissue throughout life)
4. The repair of fractures (breaks in bones) throughout life

Question 13

What is Bone remodelling?

Answer 13

a continuous process as old bone tissue is replaced with new tissue

Question 14

What is bone resorption and bone deposition?

Answer 14

Bone resorption is the removal of minerals and collagen by osteoclasts

Bone deposition is the addition of minerals and collagen by osteoblasts

Question 15

What is the definition on fracture?

Answer 15

A fracture is any break in a bone

Question 16

What are the 4 different types of fractures?

Answer 16

Partial: an incomplete break across the bone, such as a crack

Complete: a complete break across the bone; that is, the bone is broken into two or more pieces

Closed (simple): the fractured bone does not break through the skin

Open (compound): the broken ends of the bone protrude through the skin

Question 17

Repair of a fracture involves several steps:

Answer 17

1. Phagocytes begin to remove any dead bone tissue
2. Chondroblasts form fibrocartilage at the fracture site that bridges the broken ends of the bone
3. fibrocartilage is converted to spongy bone tissue by osteoblasts
4. Bone remodelling occurs, in which dead portions of bone are absorbed by osteoclasts and spongy bone is converted to compact bone

Question 18

Bone growth, repair and remodelling all require multiple factors to be successful

Answer 18

Adequate minerals for bone matrix (calcium, phosphorus and magnesium)

Vitamins A, C, and D

Hormones such as hGH and insulin like growth factors (IGF)

Weight-bearing exercise that places stress on bones

Question 19

The adult human skeleton consists of how many bones, and which are grouped in what two principal divisions?

Answer 19

206 bones

Axial skeleton: Consists of the 80 bones that lie around the midline of the human body: the bones of the skull, auditory ossicles (ear bones), hyoid bone, ribs, sternum and vertebrae

Appendicular skeleton: contains 126 bones of the upper and lower limbs or appendages plus the bone groups called girdles that connect the limbs to the axial skeleton

Question 20

What is a joint?

Answer 20

A joint (articulation) is a point of contact between cartilage, or between teeth and bone

Question 21

Structural classification of joints is based on 2 criteria:

Answer 21

Presence or absence of a synovial cavity, a space between the articulating bones

Type of connective tissue that holds the bones together

Question 22

Functional classification of joints relates to the degree of movement they permit

Answer 22

Synarthrosis- immovable joint

Amphiarthrosis- slightly movable joint

Diarthrosis- freely moveable joint

Question 23

What are the 3 types of joints?

Answer 23

Fibrous
Cartilaginous
Synovial

Question 24

Fibrous Joints (Functional classification & 3 types of fibrous joints)

Answer 24

Permit little or no movement.

3 types of fibrous joints:
Syndesmosis- joint permits limited movement
Suture- fibrous joint that may be a slightly moveable or immovable
Interosseous Membranes- permits slight movement

Question 25

Cartilaginous Joints (Functional classification & 3 types of fibrous joints)

Answer 25

Allows little or no movement.

3 types of cartilaginous joints are:
Synchondrosis- immovable joint
Symphysis- slightly movable joint
Epiphyseal Cartilages- growth centre during endochondral bone formation

Question 26

Synovial Joints (Functional classification)

Answer 26

Unique characteristic of a synovial joint is the presence of a space called a synovial (joint) cavity between the articulating bones

Allows a joint to be freely moveable

Question 27

What are the 6 types of synovial joints?

Answer 27

Plane, Condyloid, Hinge, Saddle, ball-and-socket, Pivot

Question 28

3 types of muscle tissue? (what is it? straited or not? voluntary or involuntary)

Answer 28

Skeletal muscle tissue: mostly attached to bones. Striated and voluntary.

Cardiac muscle tissue: forms most of the wall of the heart. Striated and involuntary.

Smooth muscle tissue: located in viscera. Nonstriated and involuntary.

Question 29

Muscular tissue has 5 key functions:

Answer 29

Producing body movement
Stabilising body positions
Regulating organ volume
Moving substances within the body
Producing heat