Lecture 2 - Bone Remodeling Flashcards
_____ canals are the central canals that form in the center of osteon units. ____ essentially wrap around these vascular pores, forming the cortical bone around it.
Haversion
Lamellae
Trabeculae in heads of long bones, like the femur, take on an _____ formation that distributes the load the bone bears,
Arcade
At 26 days development, upper _____ buds appear, which are important for patterning of the musculoskeletal system.
Upper Limb Buds
At about 32 days development, first ______ contractions are observed, and are important for developing the proper function of joints.
Muscle
The cranium and shoulder girdle are formed from embryonic ____, the post cranial skeleton (the rest of the bones) is formed from embryonic _____.
Ectoderm
Mesoderm
Collagen synthesis begins with the generation of procollagen ____ chains with _____ ends, which are what allow the coiling of the collagen molecule into triple helicies. Once the collagen molecules are secreted out of the cell, the _____ ends are cleaved to allow for proper arrangement of the molecules into fibrillar structures which are reinforced by covalent cross-linking facilitated by the enzyme ____ oxidase.
Alpha chains
Propeptide
Propeptide
Lysyl oxidase
_____ are the cells primarily responsible for creation of cartilage. They are derived from _____ stromal cells. As it matures, it moves into the _____ (newly formed boned), and then differentiates into ______ as it moves into the mineralized bone.
Osteoblasts
Mesenchymal stromal cells
Osteoid
Osteocytes
Type ___ collagen is comprised of two alpha I strands and one alpha II strand. The 300nm periodicity of collagen “striping” is very important to the structure and function of the collagen fibers, allowing them to bend and kink. The overlapping region accounts for about ___% of the tropocollagen length. Together with the Lacunar region, this accounts for exactly ___nm.
Type I collagen
10%
67nm
Cartilage is comprised of Type ___ collagen.
Type II
The energy that it takes to cause bone to fail is termed _____.
Toughness
______ refers to cells’ ability to sense and respond to mechanical events. It has three main components:
- ______ –> cells’ detection of mechanical stimulus outside of cells and relay message inside.
- ______ –> biochemical and cytoskeletal relaying of the message within the cells.
- ______ –> signal reaches its target, the target is activated, causing alterations in cell behavior.
Mechanotransduction
- Mechanoreception
- Signal Transmission
- Target Activation
_____ are dynamic structures that grown and shrink. They are found in ____ and ____ and are often associated with molecular motors that transport intra-cellular vesicles.
Microtubules
Cilia and Flagella
_____ (actin filaments), are comprised of ____ and ____. They are more mechanical in structure, and are found adjacent to the cell _____.
Microfilaments
F-actin
G-actin
cell Membrane
_____ junctions connect cells in epithelial tissue, and are important in mechanical signal transduction between cells.
Adherens
_____, the “all purpose glue,” connects the cytoskeleton/nucleus to the ECM, allowing for mechanical signal transduction.
Fibronectin