Skeletal Systems

Question 1

Axial Skeleton

Answer 1

Bones of the skull, vertebral column, ribs, and sternum

Question 2

Appendicular Skeleton

Answer 2

Bones of the upper and lower limbs

Question 3

Cartilage

Answer 3

Avascular form of connective tissue consisting of extracellular fibers embedded in a matrix that contains cells localized in small cavities. Nourished by diffusion (no blood vessels, lymphatics, or nerves)

Question 4

Functions of cartilage (3)

Answer 4

1. Support soft tissue
2. Provide smooth, gliding surface for bone articulations at joints
3. Enable the development and growth of long bones

Question 5

Hyaline Cartilage

Answer 5

Most common type of cartilage; Matrix contains a moderate amount of collagen fibers (i.e. articular surfaces of bones)

Question 6

Elastic Cartilage

Answer 6

Matrix contains collagen fibers along with a large number of elastic fibers, (i.e. external ear)

Question 7

Fibrocartilage

Answer 7

Matrix contains a limited number of cells and ground substance amidst a substantial amount of collagen fibers (i.e. intervertebral discs)

Question 8

Bone

Answer 8

Calcified, living, connective tissue that forms the majority of the skeleton. Consists of intercellular calcified matrix which also contains collagen fibers and several types of cells within the matrix. Vascular and innervated

Question 9

Bone functions (5)

Answer 9

1. Supportive structure for body
2. Protectors of vital organs
3. Reservoirs of calcium and phosphorus
4. Levers on which muscles act to produce movement
5. Containers for blood-producing cells

Question 10

Compact Bone

Answer 10

Dense bone that forms outer shell of all bones and surrounds spongy bone

Question 11

Spongy Bon

Answer 11

Consists of spicules of bone enclosing cavities containing blood-forming cells (marrow)

Question 12

Long bones

Answer 12

Tubular (humerus, femor)

Question 13

Short bones

Answer 13

Cuboidal (bones of wrist and ankle)

Question 14

Flat bones

Answer 14

Consist of two compact bone plates separated by spongy bone (skull)

Question 15

Irregular bones

Answer 15

Bones with various shapes (bones of face)

Question 16

Sesamoid bones

Answer 16

Round or oval bones that develop in tendons

Question 17

Periosteum

Answer 17

Fibrous connective tissue membrane that surrounds bones except in area of joint where articular cartilage is present. Required for bone to survive. Receives blood vessels whose branches supply outer layers of compact bone. Supplied with numerous sensory nerve fibers (unlike bone itself) and very sensitive to any type of injury.

Question 18

Bone comes from ____

Answer 18

From mesenchyme by either

1. Intramembranous ossification (mesenchymal models of bone undergo ossification)
2. Endochondral ossification (cartilaginous models of bones form from mesenchyme and undergo ossification)

Question 19

Red marrow

Answer 19

aka Myeloid Tissue
Most marrow is red at birth.
Give rise to red blood cells, platelets, and most white blood cells arise.
More red marrow is converted into yellow marrow within the medulla of the long and flat bones.

Question 20

Yellow marrow

Answer 20

Dominated by large fat globules

Makes a few white cells

Question 21

Hemopoietic stem cells

Answer 21

Stem cells of bone marrow that give rise to white blood cells, red blood cells, and platelets.

Question 22

Mesenchymal stem cells

Answer 22

Stem cells of bone marrow that differentiate into structures that form bone, cartilage, and muscle

Question 23

Bone fractures typically caused by

Answer 23

Abnormal load or stress, poor quality (osteoporosis)

Question 24

Avascular necrosis

Answer 24

Cellular death of bone resulting from a temporary or permanent loss of blood supply to the bone

Question 25

Osteoporosis

Answer 25

Bone mineral density is significantly reduced, common in postmenopausal women

Question 26

Factors leading to osteoporosis

Answer 26

Poor diet, steroid usage, smoking, premature ovarian failure

Question 27

Synovial joints

Answer 27

Connections between skeletal components where the elements involved are separated by a narrow articular cavity. Described based on shape and movement

Question 28

Hyaline cartilage

Answer 28

Covers articulating surfaces of skeletal elements in synovial joints

Question 29

Synovial membrane

Answer 29

Attaches to margins of the synovial joint surfaces at the interface between the cartilage and bone and encloses the articular cavity

Question 30

Fibrous membrane

Answer 30

Formed by dense connective tissue and surrounds and stabilizes the synovial joint, parts may thicken to form ligaments

Question 31

Joint capsule

Answer 31

Consists of an inner synovial membrane and an outer fibrous membrane

Question 32

Articular discs

Answer 32

Absorb compression forces, adjust to changes in the contours of joint surfaces during movements, and increase the range of movements that can occur at joints.

Question 33

Fat pads

Answer 33

Usually occur between the synovial membrane and the capsule and move into and out of regions as joint contours change during movement

Question 34

Plane joints

Answer 34

Allow sliding or gliding movements when one bone moves across the surface of another

Question 35

Hinge joints

Answer 35

Allow movement around one axis that passes transversely through the joint; permits flexion and extension

Question 36

Pivot joints

Answer 36

Allow movement around one axis that passes longitudinally along the shaft of the bone; permit rotation

Question 37

Bicondylar joints

Answer 37

Allow movement mostly in one axis with limited rotation around a second axis; formed by two convex condyles that articulate with concave or flat surfaces

Question 38

Condylar (ellipsoid) joints

Answer 38

Allow movement around two axes that are at right angles to each other; the articular surfaces are saddle shaped; permit flexion, extension, abdustion, adduction, and circumduction

Question 39

Ball and socket joints

Answer 39

Allow movement around multiple axes; permit flexion, extension, abduction, adduction, circumduction, and rotation

Question 40

Solid joint

Answer 40

Connections between skeletal elements where the adjacent surfaces are linked together either by fibrous connective tissue or by cartilage. More restricted movement

Question 41

Sutures

Answer 41

Fibrous joint, occurs only in skull where adjacent bones are linked by a thin layer of connective tissue termed a sutural ligament

Question 42

Gomphoses

Answer 42

Fibrous joint, occur only between the teeth nd adjacent bone

Question 43

Syndesmoses

Answer 43

Fibrous joint, two adjacent bones are linked by a ligament

Question 44

Synchondroses

Answer 44

Cartilaginous joint, occurs where two ossification centers in a developing bone remain separated by a layer of cartilage. Joints allow bone growth and eventually become completely ossified

Question 45

Symphyses

Answer 45

Cartilaginous joint, occurs where two separate bones are interconnected by cartilage

Question 46

Degenerative joint disease

Answer 46

Osteoarthritis or osteoarthrosis. Commonly caused by decreases in water and proteoglycan content within cartilage

Question 47

Arthroscopy

Answer 47

Technique of visualizing the inside of a joint using a small telescope placed through a tiny incision in the skin