Lesson 2: Types of Bones

Question 1

➢ is a rigid connective tissue
➢ the hardest tissue in the body

Answer 1

Bone

Question 2

Bone Tissue is also called as …

Answer 2

Osseous Tissue

Question 3

hardness of bones depends on…

Answer 3

▪ crystallized inorganic mineral salts
▪ organic collagen fibers

Question 4

➢ initiated by osteoblasts (bone building cells)
➢ simply occurred when enough mineral salts were present to form crystals
➢ occurs only in the presence of collagen

Answer 4

Calcification

Question 5

Types of Bone According to Distribution of Spaces

Answer 5

Compact Bone
Spongy Bone

Question 6

➢ Dense, strong, with closely spaced lamellae (concentric layer of mineral deposits)
➢ Forms the external layer of all bones of the body and bulk of the diaphysis of long
bones
➢ Provides protection and support
➢ Helps the long bones resist the stress of weight placed on them
➢ Has many osteons/ Haversian system

Answer 6

Compact Bone

Question 7

the basic functional unit of the compact bone

Answer 7

Osteons or Haversian System

Question 8

➢ Porous, light and weaker
➢ With widely spaced lamellae
➢ Does not contain true osteons (incomplete Haversian system)
➢ Consists of lamellae arranged in an irregular lattice work of thin plates of bone

Answer 8

Cancellous/Spongy Bone

Question 9

lamellae arranged in an irregular lattice work of thin plates of bone

Answer 9

Trabeculae

Question 10

Types of Bone According to Shape

Answer 10

Long Bones
Short Bones
Flat Bones
Irregular Bones
Sesamoid Bones
Accessory Bones

Question 11

➢ Classified as such when its length is greater than its width
➢ Located in the extremities
➢ E.g. femur (longest bone), humerus, radius
➢ Acts as levers that are pulled out by contracting muscles

Answer 11

Long Bones

Question 12

➢ Have equal length, width and thickness but irregular in shape
➢ E.g. carpal, tarsal

Answer 12

Short Bones

Question 13

➢ thin and flat
➢ has two thin layers of compact bone with spongy bone tissue between them
➢ RBC are manufactured
➢ protection of body organs
➢ translucent and thin
➢ e.g. ribs, scapulae, cranial bones, sternum

Answer 13

Flat Bones

Question 14

➢ bones that do not fit in any category
➢ comes in different shapes
➢ e.g. facial bones, hip bone, mandible, vertebra

Answer 14

Irregular Bones

Question 15

➢ resemble sesame seeds -small and round
➢ found adjacent to joints
➢ e.g. patella (knee cap)
➢ eliminates friction
➢ provides slight support and protection

Answer 15

Sesamoid Bones

Question 16

➢ most commonly found in the feet
➢ usually occur when developing bones do not fuse completely
➢ may look like extra bores/broken bones in X-rays
➢ add some slight support and protection to the area of the skeleton where they are
found

Answer 16

Accessory Bones or Supernumerary Bones

Question 17

Gross Anatomy of Long Bones

Answer 17

Diaphysis
Epiphyses
Metaphysis
Articular Cartilage
Endosteum
Periosteum
Medullary Cavity/ Marrow Cavity

Question 18

➢ shaft or long main portion of the bone
➢ hollow cylinder which contains medullary yellow bone marrow in adult
➢ primarily a storage area for adipose tissue

Answer 18

Diaphysis

Question 19

➢ distal and proximal extremities or ends of the bone
➢ composed of spongy bone covered by thin layer of compact zone
➢ contains red marrow (where some RBC’s are manufactured during childhood and
adolescence)
➢ erythropoietic activity in the adult mainly occurs in the flat bones and vertebrae
- wider than the shaft

Answer 19

Epiphyses (Proximal & Distal)

Question 20

➢ region in a mature bone where the diaphysis joins the epiphysis
➢ made up of epiphyseal plate and the adjacent bony trabeculae

Answer 20

Metaphysis

Question 21

➢ thin layer of hyaline cartilage covering the epiphysis; where the bone forms an
articulation with another bone
➢ provides a smooth, slippery surface that decreases friction at joint movement,
absorbs shock at freely movable joints

Answer 21

Articular Cartilage

Question 22

➢ membrane that lines the internal cavities of bones
➢ covers the trabeculae of spongy bone tissue
➢ contains osteoprogenitor cells and osteoclasts

Answer 22

Endosteum

Question 23

➢ strong fibrous membrane that covers and protects the diaphysis
➢ has the potential to form bone during growth periods and in fracture healing
➢ contains nerves, lymphatic vessels, blood vessels and bone cells necessary for
growth, repair and nutrition
➢ gives the distinctive pink color of living bone

Answer 23

Periosteum

Question 24

layer of periosteum
composed of dense, irregular connective tissue containing blood vessels lymphatic vessels and nerves that pass into the bone

Answer 24

Outer Fibrous Layer

Question 25

layer of periosteum contains elastic fiber, blood vessels, and bone cells

Answer 25

Inner Osteogenic Layer

Question 26

central part of the structure space within the diaphysis that contains the fatty yellow bone marrow in adults

Answer 26

Medullary Cavity or Marrow Cavity

Question 27

Two Kinds of Bone Marrow

Answer 27

Red Marrow & Yellow Marrow

Question 28

➢ found at the epiphyses of long bones and at the center of other bones ➢ found in all cancellous bones of children ➢ forms RBCs, platelets and WBCs ➢ in adults, located in the cancellous bone of me vertebrae, hips, sternum, ribs, cranial bones, and proximal ends of the femur and humerus

Answer 28

Red Marrow

Question 29

➢ found chiefly in the medullary cavity of a long bone ➢ composed of adipose tissue ➢ fat storage

Answer 29

Yellow Marrow

Question 30

Microscopic Anatomy of Bones

Answer 30

Osteon Central/Haversian Canals Lamellae Lacunae Canaliculi Volkmann's Canals/ Perforating Canals

Question 31

➢ Haversian system ➢ basic functional unit of compact bone ➢ cylinders of calcified bone ➢ only seen in adult compact tissue

Answer 31

Osteon

Question 32

➢ found in the center of the osteon ➢ enclosed by concentric lamellae ➢ usually run longitudinally thru the bone ➢ contains nerves, lymphatic vessels and blood vessels supplying the bone

Answer 32

Central Canal or Haversian Canal

Question 33

➢ ring of hard, calcified matrix ➢ concentric cylindrical layer of calcified bone ➢ makes up cylinders of Osteons

Answer 33

Lamellae

Question 34

➢ "little lakes" ➢ small spaces between the lamellae ➢ tiny cavities arranged in concentric circles where osteocytes are found

Answer 34

Lacunae

Question 35

➢ tiny canals radiating from the lacunae to all directions ➢ filled with ECF and slender, fingerlike processes of osteocytes ➢ connect lacunae with one another and eventually with the central canals ➢ provides many routes for nutrients and 02 to each the osteocytes and wastes to diffuse away

Answer 35

Canaliculi

Question 36

➢ serves as communication pathway from the outside of the bone to is inferior ➢ where blood vessels, lymphatic vessels, and nerves from the periosteum penetrate the compact bone

Answer 36

Volkmann's Canals or Perforating Canals

Question 37

Types of Bone Cells

Answer 37

Osteogenic/Osteoprogenitor Cells Osteoblasts Osteocytes Osteoclasts Bone Lining Cells

Question 38

➢ unspecialized cells derived from mesenchyme (tissue from which all connective tissues are derived) ➢ can undergo mitosis and develop into osteoblasts during time: of stress and healing ➢ found in the inner portion of periosteum, in the endosteum and in the canals of the bone that contain blood vessels

Answer 38

Osteogenic/

Question 38

➢ unspecialized cells derived from mesenchyme (tissue from which all connective tissues are derived) ➢ can undergo mitosis and develop into osteoblasts during time: of stress and healing ➢ found in the inner portion of periosteum, in the endosteum and in the canals of the bone that contain blood vessels

Answer 38

Osteogenic/Osteoprogenitor Cells

Question 39

➢ “blast” – “sprouts/buds” ➢ Immature bone cells ➢ Bone forming, repairing, bone building cells ➢ Secretes matrix ➢ Cells responsible in bone formation

Answer 39

Osteoblasts

Question 40

➢ “cytes” – maintain the tissue ➢ Mature bone cells derived from osteoblasts that had become entrapped in matrix ➢ Principal cells of fully developed bone tissue ➢ Have no mitotic potential ➢ No longer secrete matrix material found on the surfaces of bone but as they surround themselves with matrix materials they become trapped on their own secretion and become osteocytes Function: maintain daily cellular activities of bone tissue, such as the exchange of nutrients and wastes with the blood

Answer 40

Osteocytes

Question 41

➢ “clasts” – to break ➢ Engulf necrotic cells ➢ Settle on the surfaces of bone ➢ Bone destroying cells- phagocytic function ➢ Prevents bone from breaking too thick

Answer 41

Osteoclasts

Question 42

➢ Derived from the osteoblasts that cease their physiologic activity and flatten out on the bone surface ➢ Found on the surface of most bones in the adult skeleton

Answer 42

Bone Lining Cells

Question 43

Two Major Types of Surface Markings

Answer 43

Depression and Openings Processes

Question 44

➢ indentations in the grooves of bone ➢ allow the passage of soft tissues ➢ form joints

Answer 44

Depression and Openings / Cavities

Question 45

➢ any prominent projections or outgrowths that form joints ➢ serve as attachments for ligaments and tendons

Answer 45

Processes

Question 46

Six Types of Depression and Openings

Answer 46

Fissure Foramen Meatus Paranasal Sinuses Grooves / Sulcus Fossa

Question 47

➢ an opening thru which blood vessels, nerves or ligaments pass

Answer 47

Foramen ➢ e.g. Foramen Magnum, Obturator foramen

Question 48

➢ a narrow cleft-like opening between adjacent parts of bones through which blood vessels and nerves pass

Answer 48

Fissure ➢ e.g. Superior Orbital Fissure

Question 49

➢ a tube like passageway running within a bone

Answer 49

Meatus ➢ e.g. External auditory meatus (ear canal)

Question 50

➢ an air-filled cavity within a bone connected to the nasal cavity ➢ purpose: give resonance to the voice

Answer 50

Paranasal Sinuses ➢ e.g. Frontal sinus

Question 51

➢ Furrow/depression that accommodates a soft structure such as blood vessels, nerve or tendon

Answer 51

Grooves / Sulcus ➢ e.g. depression on the anterior surface of the humerus

Question 52

➢ a depression in or on a bone

Answer 52

Fossa ➢ e.g. olecranon fossa; acetabulum

Question 53

Three Types of Processes

Answer 53

Condyle Head Facet

Question 54

Seven Types of Processes to which Tendons, Ligaments, and other Connective Tissue Attached

Answer 54

Tubercle Tuberosity Trochanter Crest Line Spinous Process Epicondyle

Question 55

➢ small rounded process/ projection

Answer 55

Tubercle ➢ e.g. Upper end of the humerus, articular tubercle

Question 56

➢ a large, usually rounded projection

Answer 56

Tuberosity ➢ e.g. tibial and radial tuberosity, sacral tuberosity

Question 57

➢ a large, blunt projection found only on the femur

Answer 57

Trochanter ➢ e.g. greater and lesser trochanter of the femur

Question 58

➢ a prominent border or ridge

Answer 58

Crest ➢ e.g. iliac crest

Question 59

➢ a less prominent ridge than a crest

Answer 59

Line ➢ e.g. linea aspera -posterior femur

Question 60

➢ sharp, slender process

Answer 60

Spinous Process ➢ e.g. spines of the vertebrae

Question 61

➢ a prominence above a condyle

Answer 61

Epicondyle ➢ e.g. lateral and medial Epicondyle of humerus and femur

Question 62

- a smooth, large rounded, articular projection

Answer 62

Condyle

Question 63

- a smooth, large rounded, articular projection

Answer 63

Condyle

Question 64

- a rounded articular projection supported on the constricted portion (neck) of a bone

Answer 64

Head

Question 65

- a smooth, flat surface

Answer 65

Facet