Skeletal system/tissues, joints and skeletal muscle
Skeletal system/tissues
Joints
Skeletal Muscle
Major functions of the skeletal system
major structural components: Bone is comprised of 35% organic material (cells and ECM), 65% inorganic material (Calcium and phosphate). Tendons and ligaments comprised of dense regular connective tissue. Elastic, hyaline and fibrocartilage.
Compact bone and spongy bone characteristics/features
components of a long bone
red and yellow bone marrow
Types of bone cells
fibrous joints
cartilaginous joints
synovial joint components
structural types of synovial joints
functions-produce movement, open and close passageways, maintain posture and stabilize joints, generate heat.
properties-contractility, excitability,extensibility, elasticity.
connective tissue layers
components of a skeletal fiber
Osteocyte-matured osteoblasts that maintain hard bone.
Osteoblast-derived from stem cells. Function to produce extracellular matrix.
Osteoclast-created from leukocytes that form one big multinucleated cell. Their function is to destroy bone.
Compact bone-located on the outside of bones. More mineral storage here which is makes it very hard.
Spongy bone-located on the inside of bones. Comprised of trabeculae.
Movement
Support
Mineral Storage
Nutrient Storage
Blood cell formation
Diaphysis
Epiphysis-proximal and distal
periosteum
endosteum
spongy bone
compact bone
epiphyseal line/plate
Red bone marrow is a gelatinous material found inside all bones until the age of about 7 when it transition to yellow bone marrow which is primarily nutrient storage (fat). Red bone marrow remains in vertebrae, coxal, sternum, ribs and bones of the skull and its main function is to produce red blood cells. Side note-yellow will transition back to red in a starvation state.
gomphosis-articulation between tooth and alveoli. Held together by periodontal ligament.
synchondrosis-articulation joined by articular (hyaline) cartilage. Example: epiphyseal plate. Imovable joint.
syndesmosis-joints connect with dense regular connective tissue. Little movement. Example: carpals, tarsals, and distal tibiofibular joint.
symphysis-located at the pubic symphysis and intervertebral joints. Ends of bones have a layer of articular cartilage and at point of articulation there is a layer of fibrocartilage. Slightly moveable
sutures-bones joined by very short interconnecting fibers. Imovable joint. Example: sutures on the cranium
Intraarticular space. Joint cavity is surrounded by a joint capsule made up of 2 layers. Outer layer is dense irregular connective tissue which attaches to the periosteum. Inner (deep) layer is synovial membrane composed of areolar connective tissue which secretes synovial fluid. This functions for lubrication, shock absorption and nourishes articular cartilage.
1) Plane joint-nonaxial movement. Flat articular surface. Gliding motion.Example: intercarpal joints, joints between vertebral articular surfaces.
2) Hinge joint-uniaxial movement. Flexion and extension. Medial/lateral axis. Example: elbow, interphalangeal joints, knee, hip.
3) Pivot joint-uniaxial movement. Rotation, supination, pronation. Sleeve (bone and ligament) and axle (rounded bone). Example: proximal radioulnar joints, atlantoaxial joint.
4) Condylar joint-biaxial movement. oval articular surfaces. medial/lateral axis; anterior/posterior axis. Flexion and attention. Adduction and abduction. Example: knuckles, wrist joints.
5) Saddle joint-biaxial movement. Articular surfaces are both concave and convex. Medial/lateral axis; anterior/posterior axis. Flexion and extension; adduction and abduction. Example: thumb joint.
6) Ball and socket joint-multiaxial movement. Throwing a ball. Cup (pocket) and spherical head (ball). Flexion and extension. Adduction and abduction. Rotation.
epimysium-dense irregular connective tissue binds fascicles together.
perimysium-dense irregular connective tissue that covers each individual fascicle; blood vessels with in.
Endomysium-with in individual muscle fibers. Composed of mostly reticular fibers. Creates space and allows for very small blood vessels to run next to muscle fibers.
Deep fascia-bundles groups of whole muscles together with dense irregular connective tissue.
sarcolemma-membrane around individual muscle cell/
myofibril-make up muscle fibers
transverse (T) tubules-sarcolemma inside the muscle cell.
sarcoplasmic reticulum-smooth endoplasmic reticulum.
Terminal cisternal reticulum-storage of calcium for muscle contraction.
protection
perforating canals
articular cartilage
medullary cavity
Osteogenic cells-stem cells located in the periosteum and endosteum.