The Skeletal system part 1 Flashcards
Process
Projection extending beyond the main body of
the structure
Functions of the skeletal system
Hematopoiesis
Protection
Fat storage
Support
Movement through the locomotor system
Condyle
a rounded projection at an articular
extremity
Coracoid or coronoid process
beaklike process
Crest
ridge-like projection
Epicondyle
Projection above condyle
Head
expanded portion of a long bone
Malleolus
: club-shaped process
Trochanter
large rounded process located at a
junction of the neck and shaft of the femur
Groove
shallow linear depression
Bone
is a hard, dense connective tissue that forms most of the adult skeleton,
Cartilage
a semi-rigid
form of connective tissue, provides flexibility and smooth surfaces for movement
classification of Bones
a. Long bones
b. Short bones
c. Flat bones
d. Irregular bones
e. Sesamoid bones
long bones
Comprise of a
cylindrical shaft and two heads at both ends examples; Bones of the limbs - Femur, radius
and ulna, humerus, tibia, fibula, metatarsal,
phalanges
short bones
They are cube-shaped and
don’t have shaft and heads
function of short bones
*Responsible for transmitting forces of
movement
* Provide stability
*Examples include: carpals and tarsal bones
function of long bones
for locomotion
Flat bones
Have flat wide surfaces
Functions of flat bones
*for muscle
attachment and protection of inner organs
* Examples: cranial bones, sternum, ribs, scapulae
Irregular bones
is one that does not have any easily characterized shape and therefore does not fit any other
classification
functions of irregular bones
Protect internal organs
example facial bones and vertebrae
List down the 4 bone cells
- Osteocytes
- Osteoblasts
- Osteoclasts
- Osteogenic stem
Osteoblasts
- responsible for forming new bone matrix
location of the osteoblasts
*is found in the growing portions of bone, including the
periosteum and endosteum
* at the site of fracture
Osteocyte formation
formed when osteoblast is trapped in the calcified matrix.
Osteocyte location
Lacunae
Osteocyte function
- Maintain the mineral concentration of
the bone matrix via the secretion of enzymes
Osteogenic Cells
undergo mitotic activity to form osteoclasts.
Osteoclasts function
- Maintain the shape of bones during growth
- Remove extra callus formed during healing of fractures
- responsible for bone resorption, or breakdown
location of osteoclasts
Bone surfaces and at sites of old, injured, or unneeded
bone
Types of Bone tissues
- Spongy Bone
- Compact bone
Compact Bone
- dense
- strong
- found under the periosteum in the diaphysis region of long bones
Functions of compact bones
- It provides support and protection.
Harvesian system
The microscopic structural unit of compact bone
other name of the harvesian system
- Osteon
List the components of the harvesian system
- Harvesian canal/ central canal
- Lacunae
- Lamellae
- Canaliculi
- Volkmann’s canals
Harvesian canal
A tiny channel that runs lengthwise through the center of the osteon.
Lacunae
- space or tiny cavities between lamellae that houses osteocytes
Lamellae
- Rings of hard calcified matrix that surrounds the harvesian canal.
Canaliculi
Microscopic canals radiating from lacunae connecting osteocytes.
Volkmann’s canal
- Horizontal channels connecting harvesian canals
The spongy Bone
- It has a sponge appearance
- Consists of strands of bone called trabeculae.
- Has larger haversian canal than compact bone.
- Has fewer lamellae
Other name of spongy bone
cancellous bone
trabeculae
rod-strand like stucture that forms a network of the spongy bone.
Trabeculae location
found at the ends of long bones in the spongy bone.
Parts of the bone
- epiphysis
- diaphysis
- articular cartilage
- periosteum
- endosteum
- metaphysis
- epiphyseal cartilage *
epiphysis
The ends of a developing long bones
Define osteogenesis/ ossification
is the process of the development of bones.
epiphyseal cartilage
a structure thar separates the epiphysis and the diaphysis
Endosteum
*Lines the inner surface of bones, surrounding the medullary cavity (the hollow center of most bones) where bone marrow is produced
periosteum
Covers the outer surface of bones,
function of endosteum
*Bone growth and repair: Osteoblasts on the endosteum surface lay down new bone tissue.
* Hematopoiesis: The endosteum provides a supportive environment for hematopoietic stem cells,
*Regulation of bone remodeling: Endosteum plays a part in regulating the ongoing process of bone resorption by osteoclasts and bone formation by osteoblasts.
what is a cartilage
a vascular tissue
functions of periosteum
- Muscle attachment
- Protects the underlying bone
- pain perception due to the dense nerves
- Protects muscles from injury
- Protects tendons
development centers of a bone
- primary ossification center
- secondary ossification center
how are bones used to determine the age of a person.
- The duration in which the ossification centers appear is constant therefore easy to deduce the age
secondary ossification center
- Development centres that appear after the POC
primary ossification center
- The first development centre to appear in a bone
What is the role of the periosteum in intramembranous ossification?
- The outer layer composed of dense connective tissue, provides a physical extracellular matrix that stabilizes and supports the developing bone during intramembranous ossification.
- Nutrient and Blood Supply: contains blood vessels that supply nutrients and oxygen to the developing bone tissue.
Which bones in the body are primarily formed through intramembranous ossification?
- Clavicles
- Cranial bones
- facial bones
How do osteoblasts contribute to the formation of bone during the intramembranous process?
- mesenchymal cells in the developing embryo differentiate into osteoblasts responsible for bone formation.
- Osteoblasts secrets nutrient minerals like collagen type 1 which provides structural framework for the bone.
- modified to osteocytes which maintain the mineral concentration of the bone matrix
What is the primary tissue type involved in intramembranous ossification?
mesenchyme
What artery supplies blood to the diaphysis
Nutrient artery
Artery supplying the epiphysis
Epiphyseal arteries
stages in the process of fracture healing
- Hematoma formation
- Formation of granulation tissue
- Callus formation
- Remodeling of bone
Formation of granulation tissue
- New blood cells grow into the clot
- Soft callus and fibro cartilage forms at the fracture site
Haematoma formation
- Blood vessels are broken at the site of fracture
- blood clotting
Appendicular skeleton
- shoulder girdle
- upper limb
- pelvic girdle
- Lower limb
Divisions of the skeleton
- Axial skeleton
- Appendicular skeleton
Remodeling
- Osteoclasts dissolve small bone fragments.
- Osteoblasts connect the gap between the broken ends.
Callus formation
- Minerals are deposited which harden the soft callus
- soft callus converted to hard callus of spongy bone. 4-6 weeks
Shoulder girdle
- 1 clavicle (right and left)
- 1 scapula
Pelvic girdle
- 2 innominate bones
- sacrum
Upper limb
- 1 humerus
- 1 radius
- 1 ulna
- 8 carpal bones
- 5 metacarpal bones
- 14 phalanges
Borders of the humerus
- Medial border; from medial supracondylar ridge to medial tip of bicipital groove
- Lateral border; From lateral supracondylar ridge and fades out as it goes upwards
- Anterior border; starts at the upper end of the shaft downwards
Lower limb( each side)
- 1 femur
- 1 tibia
- 1 fibula
- 1patella
- 7 tarsal bones
- 5 metartasal bones
- 14 phalanges
Surfaces of the humerus
i. Posterior surface
- Lies between the lateral and medial borders
ii. Anterolateral surface
- Lies between the anterior and lateral borders and has the
deltoid tuberosity in its upper half
iii. Anteromedial surface
- Lies between the anterior and medial borders
Surfaces of the radius
Medial surface
Anterior surface
Lateral surface
Inferior surface
Borders of the radius
1.The medial/ interosseous border
2. The posterior border
3. The anterior border
Borders of the ulnar
1.The lateral/ interosseous border
2. The anterior border
3. The posterior border
Surfaces of the ulnar
1.Anterior surface
2.medial surface
3. Posterior surface
Rows of carpal bones
- Proximal row
- Distal row
Development of bones and their sources
- flat bones develop from membranes
- Sesamoid bones develop from tendon models
- Short e
Irregular and long bones develop in the fetus from cartilage models
