Part 4

Question 1

Structure of Bone

Answer 1

the structure of bone gives it strength, the ability to grow and repair itself.

also has the ability to serve as a reservoir minerals and cells needed elsewhere in the body

the bone dynamic’s nature is possible because it is living tissue containing cells, collagen matrix, and minerals

Question 2

Histology of Bone

Answer 2

Osteocytes are star shaped cells that maintain bone and are able to sense physical stresses

Osteoblast make bone and osteoclast break it down

Question 3

Mineral resorption

Answer 3

Performed by osteoclast and it removes calcium from bone so it can enter the bloodstream

Neurons use calcium to communicate with each other and rely upon its presence in extracellular fluid for normal muscle contraction inhibition

Low levels of plasma calcium causes tetany (an involuntary and continuous contraction of skeletal muscle).

Blood clotting and other vital metabolic reactions require calcium as well.

Question 4

Osteoporosis

Answer 4

Osteoclasts liberate calcium from bone-bound reserves but when too much calcium is depleted from the bone osteoporosis results

causing bones porous of minerals and make them weak and brittle

Question 5

Osteoblast

Answer 5

Osteoblast secretions allow mineralization in bones, a process that is inhibited elsewhere in the body

This mineral deposition is in the form of hydroxyapatite a calcium phosphate salt

Osteoblast produce a highly organized collagen matrix to which extracellular hydroxyapatite binds

Question 6

Collagen

Answer 6

Collagen protein gives bone flexibility, while the minerals that encrust those fibers give them strength

brittle bone disease (osteogenesis imperfecta) results from the genetically based corruption of bone’s collagen matrix

Question 7

The structure of Bone

Answer 7

In compact bone, the mineral-laden collagen matrix is organized into long concentric layers called lamellae, layers of bones, tissues or cell walls

Between each lamella are microscopic pockets or lacunae where bone cells reside

Question 8

Canaliculi

Answer 8

Call communication between the lacunae occurs through microscopic tunnels (canaliculi) which transverse lamellae

Question 9

Osteon

Answer 9

a grouping of concentric lamellae is called an osteon and contains a central canal within its innermost ring called the central (haversian) canals and perforating (Volkmann’s) canals.

Question 10

Central (Haversian) Canals

Answer 10

are passageways for nerves and blood vessels

haversian canals and their contents, running parallel within the center of each osteon, connect by way of perpendicular and oblique perforating Volkmann’s canals.

Question 11

Compact (dense) bone

Answer 11

bone that makes up bone plates of the skull and the periphery of most other bones

Question 12

Spongy bone

Answer 12

has few osteons compared to compact (dense) bone

The spongy bone contained with compact bone allows bone to be lighter and serves as a location for bone marrow to reside

Question 13

Bone marrow

Answer 13

A soft material within spongey bone and medullary cavity of long bones.

Question 14

Red bone marrow

Answer 14

is a site of blood formation and plays a role in the immune system

Question 15

Yellow bone marrow

Answer 15

presents within the medullary cavity of adult long bones is primary composed of adipose tissue

The longest long bone of the adult body is the femur, so it contains the largest amount of yellow bone marrow

Question 16

Long Bones

Answer 16

Bones that have a pronounced longitudinal axis, provide the mechanical advantages of levers where they articulate with other bones.

Some of these points of articulation allow the associated bones to move in a hinge-like fashion relative to each other.

Question 17

Examples of bones hinge like fashion

Answer 17

Hinge joint found in each elbow and knee allows flexion and extension of the more distal bone along only one plane

The shoulders and hips are locations where long bones articulate with other bones in ball and socket joints.

Ball and socket joints allow for abduction, adduction, circumduction, and rotation of the associated long bone

Question 18

Short bones

Answer 18

ex. Bones of the wrist, ankles, and patella

short bones have a width similar to their hight and articulate as gliding joints

Question 19

Flat bones

Answer 19

Flat bones are thin bones that have a plat-like shape such as bones of the cranium, connect with each other at fused joints called sutures

Question 20

Irregular bones

Answer 20

Bones that dont fit flat, long, or short are irregular bones

Question 21

How is skeleton articulation possible?

Answer 21

Articulation of the skeleton is made possible through its association with soft tissue: cartilage, tendons, ligaments and the periosteum that covers bones

Question 22

Cartilage

Answer 22

the primary structural protein of connective tissue

Question 23

Tendons

Answer 23

Tough connective tissue that attaches muscle to bone

Question 24

Ligaments

Answer 24

a tough connective tissue that attaches bone to bone

Question 25

Periosteum

Answer 25

A thin layer that surrounds bone and its surface for attachment of tendons and ligaments

Question 26

Hyaline Cartilage

Answer 26

At the location in the skeleton where bones are involved in articulations, bone joint interfaces are protected by hyaline cartilage

as a result of trauma, cartilage can wear down to the point it offers insufficient protection.

Question 27

Osteoarthritis

Answer 27

Inflammation and pain of a joint when joint wears down

Question 28

Rheumatoid arthritis

Answer 28

causes joint inflammation and pain like osteoarthritis but is caused by an autoimmune reaction rather than wear and tear of the joint

Question 29

Epiphyseal plate

Answer 29

also called the growth plate

hyaline cartilage is also involved in bone elongation that happens in the epiphyseal plate

here, newly generated cartilage is turned into bone

an epiphyseal line develops when the plate area stops producing cartilage and indicates termination of growth in that long bone that is seen in X rays.

Anchondroplastic Dwarfism is the resulting short stature of individuals when epiphyseal plate stops growing at a premature age

Question 30

Human Skeleton’s two major division

Answer 30

Axial Skeleton and Appendicular skeleton

Question 31

Axial Skeleton

Answer 31

consists of a skull that shields the brain, a thoracic cage of ribs and sternum that shelters the heart and lugs, and a series of verterbrae in which the spinal cord resides

in addition to protective functions, the axial skeleton plays a major role in metabolism and movement

Question 32

Mastication

Answer 32

Chewing

in the skull, the mandible articulates with the temporal bone to allow for the motions of mastication

Question 33

sinuses

Answer 33

Sinuses inside the frontal, sphenoid, ethmoid, and maxillary bones are mucous membrane-lined cavities connecting with the nasal cavity

Question 34

Tiniest bones in the skull are?

Answer 34

The three auditory ossicles in the middle ears

Question 35

Hyoid bone

Answer 35

is a point of tongue and larynx attachment, and it is unique in being the only bone that is not connected to the rest of the skeleton

Question 36

Vertebral column

Answer 36

is made of three groups of similar shaped bones: the cervical, thoracic, and lumbar vertebrae

Question 37

Cervical

Answer 37

on the cranial end of the vertebral column is cervical vertebra number 1 (C1) also known as the atlas

the atlas is the rocker between C2 and the occipital bone of the skull that allows for the yes motion of head

The C2 is called the axis and it contains a vertical projection into the atlas, a pivot that allows for the no motion of the head

has 7 cervical vertebrae

Question 38

Sacrum

Answer 38

at the level of the hips, five vertebrae that fuse together by adulthood make up the sacrum, which is joined on either side by a left and right hip bone

Coccyx or tailbone is behind it

Question 39

Upper Region Appendicular Skeleton

Answer 39

Arms and legs

Upper region of the appendicular skeleton includes the pectoral girdle made of a right and left scapula and clavicles

Upper limbs consist of the humerus and more distally a pair of bones called the radius and ulna that articulate with the carpals of the wrist

The metacarpals of the palm articulate with the phalanges of the fingers

Question 40

Lower Region of the Appendicular Skeleton

Answer 40

Includes the left and right hip bones of the pelvic girdle

Lower limbs consist of the femur and more distally a pair of bones called the tibia and fibula that articulate with the tarsals of the food

Between the tarsals and the phalanges of the toes are metatarsals