the skeletal system chapter 6-9 individual bones: tissues bone cartilage epithelial tissue ...
TRANSCRIPT
Individual bones: Tissues
Bone Cartilage Epithelial tissue Fibrous connective tissue Blood Nervous tissue
Bone Structure Long bone
External structure Epiphysis, the portion of the
bone that interacts with other bones
Articular cartilage, protective layer of hyaline cartilage coating the epiphysis
Hyaline cartilage, most common type of cartilage, looks like “milky glass”
Diaphysis, long narrow portion between epiphyses, AKA: shaft
Periosteum, any part of the bone not covered by articular cartilage is protected by this tough fibrous membrane. It is a vascular tissue, functions in bone repair.
Spongy bone, branching bony plates that create irregular spaces, strong and durable because they allow for some compression.
Spongy bone makes up the bulk of the epiphysis especially in regions that are subject to compression, (weight bearing joints)
Description: the diaphysis is a semi-rigid hollow structure Medullary cavity,
hollow tube runs from end to end in the open space of the diaphysis
Lacunae, chambers arranged in concentric circles around…
Osteonic canal, pathway for arteries, veins, and nerves through the bone
Haversian System: (aka Osteon) the whole system of concentric circles and the canals associated with them
Volkmann’s canals, contain larger vessels and nerves allowing for communication of entire Haversian systems, the medullary canal, and the bone surface.
Intramembranous Bone• Broad, flat bones of the skull
• Formation–Osteoblasts become active and spongy bone is formed throughout existing membrane.
–Left over membrane becomes periosteum.
Endochondral Bone
• Most long bones
• Formation:–Masses of hyaline cartilage develop rapidly giving even the young fetus a “human” structure.
–Ossification is a gradual process•The center of the medullary cavity serves as the primary ossification center.
•Ossification occurs from the inside out.
•The secondary ossification center is formed later in the open space of the epiphysis.
•This ossification also occurs in an outward direction.
Gross Function
• Provide shape
• Support
• Protection
• Provide structure
• Serve as storage units
• Aid in body movement
• Blood cell formation
4 Parts of a Lever
1. Rod (bar)2. Fulcrum (pivot)3. Resistance ( weight being
moved.4. Force (energy supplying
movement)
Example
1. Rod: radius and ulna
2. Fulcrum: elbow joint
3. Resistance: hand and object
4. Force: biceps brachii
What is the reverse?
1. Rod: radius and ulna
2. Fulcrum: elbow joint
3. Resistance: hand and object
4. Force: triceps brachii
Once upon a time…
in the yolk sac hematopoiesis began for the embryo. Throughout life hematopoiesis continues in the …
Yellow Marrow
• Functions in fat storage.
• Inactive in hematopoiesis.
• Replaces much of the red marrow as a human ages.
Oh where oh where did the red marrow go?
While most of the red marrow is replaced by yellow marrow, red marrow for hematopoiesis does remain in the spongy bone of the…
Bone as a Storage Unit
• Bone is used to store inorganic salts. (No Carbon)
• Primarily stores Ca+
• [Ca+] control–If [Ca+] in blood is too low
osteoclasts are stimulated to breakdown bone tissue to release Ca+.
–If [Ca+] in blood is too high, osteoblasts are stimulated to form bone tissue, trapping the Ca+.
Organization
• 2 major portions–Axial: head, neck, and trunk
–Appendicular: limbs and anchoring parts
Appendicular
1. Pectoral girdle: clavicle and scapula, the attachment site of the arm.
2. Upper limb: humerus, radius, ulna, carpals, metacarpals, phalanges.
3. Pelvic girdle: 2 coxal bones forming protection for lower organs and attachment site for legs.
4. Lower limbs: femur, tibia, fibula, patella, tarsals, metatarsals, phalanges.