10/16/07 Bscc2093 Anatomy And Physiology Lecture Notes Bone Formation, Classification, Markings

Front 1

Flat Bone Formation

Intramembranous ossification

Back 1

Means within a membrane. Flat bones are formed this way. Once they are trapped in the bone they secreted, osteoblasts become osteocytes. Lots of spongy bone is filled out between the membranes.

Front 2

What is the membrane in the spinal column/skull called?

Back 2

meninges

Front 3

How long does it take the human skeleton to completely destroy/rebuild itself?

Back 3

5 years

Front 4

Long Bone Formation

Endochondrial Ossification

Back 4

Long bones are formed this way, "inside cartilage". Starts with cartilage bud, it grows from the middle out.

Front 5

Endochondrial Ossification

Primary center of chondrification

Back 5

Grows from the middle out, oldest cells in the center, at the primary center of chondrification. Old cells die, chondrocytes leave empty chambers.

Front 6

What takes over the empty chambers left by the chondrocytes?

Back 6

Osteoblasts take over the spots left by the dead chondrocytes.

Front 7

What is the primary center of ossification?

Back 7

Used to be the primary center of chondrification, now becoming ossified.

Front 8

Describe endochondrial ossification using a "cat and mouse" game metaphor.

Back 8

Cartilage is like the mouse, being chased by the bone (cat), which is always one step behind.

Front 9

Endochondrial Ossification

Secondary Centers of Ossification

Back 9

These are towards the end of the bones, radiating outward. Here, ossification continues until it meets the cartilage at the epiphyseal line at puberty.

Front 10

Classification of Bones

Long Bones

Back 10

Have diaphysis and epiphyses. Name speaks of the shape. They can be miniature, too, as in the case of phalanges.

Front 11

Classification of Bones

Short Bones

Back 11

Boxlike bones (i.e., carpals and tarsals)

Front 12

Classification of Bones

Flat Bones

Back 12

These bones are relatively flat and grown in membranes. (i.e. ribs and cranial roof, scapulae)

Front 13

Classification of Bones

Irregular Bones

Back 13

These bones come in complex shapes. (i.e. vertebrae).

Front 14

Classification of Bones

Sesamoid

Back 14

These bones are small, round, flat, inside tendons, inside membranes (i.e. patella and joints of feet)

Front 15

Classification of Bones

Sutural

Back 15

"Wormian" bones, sutures of the skull. They can be as small as grains of sand. (i.e. parietal suture, lambdoid suture, fontanalis)

Front 16

Bone Markings

Back 16

Distinctive features of bones, showing form and function. i.e., depressions grooves, tunnels for vessels, protrusions, etc.

Front 17

How are bones made thick in diameter (appositional growth)?

Back 17

Bone forms at the surface and produces ridges that parallel blood vessel. They enlarge into pockets, then meet and fuse. The grooves shrink into an osteon. This adds to the outside of bone, makes it thicker.

Front 18

What kinds of things usually attach to projections of bone?

Back 18

Ligaments and tendons

Front 19

What connects bone to bone?

Back 19

Ligaments

Front 20

What connects muscle to bone?

Back 20

Tendons.

Front 21

Bone Markings

Ramus

Back 21

Think "armlike projection, RAM = ARM backwards." (i.e. ramus of the mandible)

Front 22

Bone Markings

Trochanter

Back 22

Think "large knob (think tROCanter = ROCk)" (i.e. greater and lesser trochanters of the femur)

Front 23

Bone Markings

Tuberosity

Back 23

Think "Smaller than a trochanter, but it sticks out. (monstrOSITY = large, potato = tuber)" (i.e. ischial tuberosity = "sitz bone")

Front 24

Bone Markings

Tubercule

Back 24

Think "Smaller than a tubercule, but sticks out (cule = miniscule, potato = tuber)" (i.e. tubercule of iliac crest or rib or adductor tubercule at distal end of femur)

Front 25

Bone Markings

Condyle

Back 25

Think "rounded for something to pivot or roll, paired with a fossa or sulcus" (i.e. condyle of mandible at temporomandibular joint or the medial troclea and capitulum at distal end of humerus)

Front 26

Bone Markings

Trochlea

Back 26

Think "Pulley" or spool...tendons pass through these fibrous rings. (i.e. Medial Trochlea of distal end of humerus)

Front 27

Bone Markings

Sulcus

Back 27

Think "Sunken". A groove, crevice, furrow, trench. (i.e. intertubercular sulcus of the humerus)

Front 28

Bone Markings

Foramen

Back 28

Think "Walk-thru opening" or hole. (i.e. the foramen magnum of the skull)

Front 29

Bone Markings

Meatus

Back 29

Think "Hallway" (i.e. acoustic meatus or ear canal)

Front 30

Bone Markings

Sinus

Back 30

think "room". (i.e. ethmoid, maxillary, frontal, or sphenoid sinuses)

Front 31

Bone Markings

Fissure

Back 31

Think "Crack in a Wall" (i.e. orbital fissures behind the eye).

Front 32

How many bones are in the Axial skeleton?

Back 32

80 of the 206 bones in the body.