Exam 2 Materials Flashcards
How many bones in adult?
206 (Axial 80, Appendicular 126)
Fibrocartilage
- Lots of collagen fibers
- Very strong/resilient
- Compressed all the time & can bounce back
- 80% water
- Located: Intervertebral discs
Elastic cartilage
- Large chondrocytes
- Located: External ear
Functions of Bones
- Support
- Storage (minerals, fat in yellow bone marrow)
- Protection
- Movement
- Hemopoiesis (blood cells made in bone barrow)
Endosteum
-Covers internal surface of bones
Endochondral ossification
- Begins with hyaline cartilage
- Produces majority of bone in body
- Cartilage dies in diaphysis, periosteum forms
- Primary ossification of diaphysis
- Second ossification of epiphyses
- Medullary cavity forms
- Bone replaces cartilage (except hyaline cartilage @ ends and epiphyseal plates)
What are the 4 types of paranasal sinuses / nasal cavities?
- Frontal
- Ethmoid
- Sphenoid
- Maxillary
How many cranial?
8
Articular Cartilages
Thin layer of hyaline cartilage on epiphyses –> reduce friction between bones
What is fibrous (structural) joint? Subdivisions?
- Bones held by collagen fibers, no joint cavity
- Gomphoses
- Suture
- Syndesmoses
How does bone fracture heal?
- Hematoma (blood clot) occurs
- Fibrocartilaginous (soft) callus forms
- Bone (hard) callus replaces soft callus
- Bone remodeled
- Osteoblasts and osteoclasts involved
Synarthroses joint
- Immobile joints (most stable)
Hyaline Cartilage
- Most common
- “Glassy” - can’t see fibers, matrix is clear
- Located: Articular ends of long bones
Haversian (Central) Canal
Carries blood vessels and nerves
Amphiarthroses
-Slightly mobile joints
How is bone remodeled?
- Zone 1: Resting cartilage next to epiphyses
- Zone 2: Proliferating cartilage (making more cartilage)
- Zone 3: Hypertrophic cartilage (cartilage too big)
- Zone 4: Cartilage cells calcified (dying)
- Zone 5: Osteoblasts formed, bone remodeled by calcium
Bursa
Sacs outside most synovial joints where ligaments, muscles, tendons, bones rub
Canaliculi
Between lacunaes, allowing metabolic interactions between osteocytes
Haversian System (Osteon)
- Basic structure/functional unit of mature compact bone
- Cylindrical
- Parallel to shaft of bone
What is cartilaginous joint? Subdivisions?
Bones held by cartilage, no joint cavity.
- Synchondroses
- Symphyses
Perforating Fibers
Collagen fibers that go straight into bone
How many bones in “arm”
- 30 total
Periosteum
- Covering of bone (but not articular cartilage)
- Anchor for blood vessels/nerves
- Anchored by perforating fibers
Perichondrium
Connective tissue membrane surround outside cartilage
Perforating (Volkman’s) Canals
Perpendicular connections to central canals w/blood vessels & nerves
Synchondroses joint
- Cartilaginous joint
- Bones joined by hyalina cartilage (immobile)
- Epiphyseal plate
Syndesmoses joint
- Fibrous joint
- Between parallel bones (radius and ulna), immobile
Tendon sheaths
Elongated bursas around tendons where they rub (wrist and ankles)
How many facial bones?
14
Symphyses joint
- Cartilaginous Joints
- Bones joined by pad of fibrocartilage (slightly mobile)
- Pubic symphyses
Functions of cartilage
- Support (Elastic cartilage)
- Articulations (Hyaline cartilage and Fibrocartilage)
- Precursor for bone growth (hyaline cartilage)
Concentric Lamella
Rings around central canal
Osteogenic
- Mesenchymal stem cells
- Undergoes mitosis to make more stem cells or osteoblasts
Intramembranous Ossification
- Develops from Mesenchyme
- Produces
- Flat bones
- Some facial bones
- Mandible
- Central portion of clavicle
Diarthroses
Freely mobile joints
Trabeculae
Thin columns and plates of bone that create a spongy structure
What makes a male pelvis different from females?
- Subpubic angle 90 degrees or less
- Hips are more narrow
- Pelvic is longer
- Coccyx is vertical (female post. tilt)
- Acetabulum larger
Functions of skeletal muscle tissue
- Movement
- Maintains posture
- Regulates temperature
- Storage (don’t worry too much)
- Support
Order of skeletal muscle structural organization
- Muscle
- Fascicles (bundles of fibers)
- Muscle fiber
- Myofibrils
- Myofilaments
- Actin and Myosin
Sarcolemma
Plasma membrane of muscle fibers
Sarcoplasm
Cytoplasm of muscle fibers
Sarcoplasmic Reticulum
- Smooth ER of muscle fibers
- Stores calcium ions for muscle contractions
T-tubules
- Deep T-pouches of the sarcolemma that extends into sarcoplasm
- Function: brings stimulus down to cisternae
Terminal cisternae
Blind sacs at end of sarcoplasmic reticulum
Site of calcium ion release for muscle contraction
Epimysium
Membrane surrounds the entire muscle
Perimysium
Membrane that covers the fascicles
Endomysium
Inside a fasicles and between each muscle fiber, they electrically insulate fibers
Fasicles
Bundles of muscle fibers
Myofibrils
- Cylindrical structures of a muscle fiber that extend the whole length of cell
- Myofibrils are made up of myofilaments
Myofilaments
- Short bundles that make up myofibrils
- Do not run entire length, organized into repetitive groups
- Actin (thin) and Myosin (thick)
Titin
- Filaments of an elastic protein
- Help return myofilaments to resting position after contraction
Sarcomere
- Functional contracile unit in a skeletal muscle fiber
- Defined by area between two adjacent Z discs
- Shortens during muscle fiber contractions
H Zone
- Light central region of A band
- No thin filaments
M Line
The middle (protein) line in the H Zone that keeps the thick filaments together
Z Discs
A protein, in middle of I band, attaching to thin filaments
A band
- Dark band in middle of sarcomere
- Thick filaments only
- Lateral ends has overlapping thin filaments
- Stays constant in contractions
I band
- Light bands
- Thin filaments and titin protein only
- Narrows during contractions
Neuromuscular Junctions
Where motor neuron comes into close proximity to muscle fibers
Circular Arrangement
Orbicularis Oris
Parallel Arrangement
Rectus Abdominus
Convergent
- Triangular in shape, fibers coverge to one point
- Pectoralis major
Unipennate
- All fibers go to one side
- Extensor Digitorum
Bipennate
- Fibers go to two sides
- Rectus Femoris (thigh)
Multipennate
- Fibers go to multiple sides
- Deltoid