Unit 1 Lecture 2: Osteology Flashcards
6 Functions of Bones
Support:
framework that supports the body
Protection:
skull and ribcage
Movement:
Muscles have to act against the bones. Muscles use the bones as leverage
Mineral Storage:
Calcium and Phosphate
Blood Cell Formation: – called hematopoiesis, occurs in red bone marrow
Triglyceride Storage:
Fat and energy storage. Adipose tissue is what yellow bone marrow is composed of.
How Many Named Bones are There?
206 named bones
Two Principal Divisions of Skeleton:
Axial:
Bones that lie around the longitudinal axis of the human body.
Include the skull, ribcage, spine, etc.
Appendicular
Bones within the upper & lower limbs, as well as the bones that connect the limbs to the axial skeleton (i.e. the girdles)
Includes the scapula, clavicle, coxal bone, etc.
5 Classification of Bones:
Long Short Flat Irregular Sesamoid
Long Bones
Are longer than they are wide.
Have a shaft portion and 2 end parts.
Found in the limbs.
Include phalanges
Short Bones
Cube-ish in shape.
Include the Ankles.
Flat Bones
Includes the sternum, the ribs, and the bones of the skull
Irregular Bones
Includes the vertebrae
Sesamoid
a type of short bones.
They are found in tendons.
Tendons connect muscles to bones.
Sesamoid Bones help alter the direction of the pull of a tendon.
Includes the patella and others that don’t have names and can differ from person to person.
Texture of Bones:
Compact Bone
Spongy Bone
Compact Bone
Dense.
Vascularization
Spongy Bone
Found on the inside of the Compact Bone exterior.
Trabeculae: Bone spicules laid along stress lines.
In between the Trabeculae, there is is red and yellow bone marrow
Spongy Bone remodels over time.
We replace about 10% of it every year.
Long Bone Structure
Diaphysis
(containing medullary cavity or marrow cavity containing red or yellow bone marrow)
Epiphyses
Epiphyseal Plate (Hyaline Cartilage) OR Epiphyseal Line (Bone)
Membranes
(Periosteum & Endosteum)
Articular Cartilage
(Type of Hyaline Cartilage)
The Periosteum and the Endosteum
The Periosteum: much thicker, fibrous than the endosteum. Tendons attach to Periosteum
Along the internal passageways: endosteum. Not thick. Made of Osteoglass bones which build bone, and Osteoclass cells (break down bones). Bone remodeling cells.
Sharpies fibers anchor the Periosteum to the bone
diaphysis
The Shaft of a Long Bone
Marrow Cavity
holds red or yellow marrow
As you age, red marrow changes to mostly yellow marrow.
As adults, there’s only a couple places with it: The Heads of the Humorous, Femur, and Hip Bones
If a person is ill, the yellow will sometimes change back to red marrow
Epiphyses sometimes also have marrow
Epiphyseal plate:
Made of connective tissue, hyalin cartilage.
Important for the lengthening of the bone.
Present in children.
As an individual matures, the plate is replaced with a line of bone.
Important for forensics for aging a human specimen.
Articular Cartilage
Articular cartilage:
hyaline cartilage that absorbs stress
“Articulation” refers to joint
Similarities of Short, Flat, Irregular, and Sesamoid
Bone Structure
Simpler layout than the long bone.
No medullary cavities or shafts
Membranes are still present though: periosteum and endosteum
Also includes marrow throughout the bone in the bone spicules of the dipole of the spongy bone
What is the name of thecentral cavity in thediaphysis of a long bone where red/yellow marrow is found?
Medullary cavity
Perferating (Sharpey’s) fibers are collagen filbers that connect the_______.
periosteum to theunderlying bone
An important function of the skeletal system is _________.
protection of the brain andvisceral organs
What bone is CORRECTLY matched with the proper skeleton?
A)Scapula - appendicular skeleton
B)Carpal bones - axial skeleton
C)Sternum - appendicular skeleton
D)Clavicle - axial skeleton
E)Femur - axial skeleton
Scapula - appendicular skeleton
What is found covering the ends of long bones?
Articular cartilage
All the bones are classified correctly EXCEPT for:
A)Vertebrae - irregular bone
B)Humerus - long bone
C)Sternum - flat bone
D)Ribs - flat bone
E)Carpal bones - long bone
Carpal bones - long bone
An x-ray determined that Jonathan fractured the shaft of his humerus. This means that the break is in the _______ of the bone.
diaphysis
Which structure is composed of hyaline cartilage and allows for the lengthwise growth of long bones?
Epiphyseal plate
The bones in the long or longitudinal axis of the body make up the _______.
axial skeleton
The term diploë refers to the ________.
internal layer of spongy bone in flat bones
The bone spiculesassociated with spongy bone are called_______.
trabeculae
