NURS 301 Lecture 2: Week 2 - 4.2
Skeletal System and
Articulations
Functions of Skeletal System
Support, protection
-
Movement with muscles
-
Blood cell production
-
Storage of minerals for other functions
-
Helps with pH balance
-
Absorbs contaminants from blood
-
What does the Skeletal System consist of?
Bones
-
Cartilage
-
Ligaments: connects bone to bone
-
Tendon: bone to muscle
-
Tissues
Connective tissue: bone (osseous), blood, fibrous, adipose
○
Nervous
○
-
Osseous (Bone) Tissue and Bonep
Bone Tissue Composition
Connective tissue with hard matric
-
Collagen fibers ---> flexibility and strength
-
Mineral salts including Ca3PO4 and CaCO3 deposit on
fibers ---> hardness and resists compression
Calcium
○
Phosphate
○
Carbonate
○
Organic compound: collagen
○
-
Bone Cells
Osteocyte: mature bone cell that maintains bone matric
-
Osteoblast: immature bone cell that secretes organic
components of matric
-
Osteoprogenitor cell: Stem cell whose divisions produce
osteoblasts
-
Osteoclasts: multinucleate cell that secretes acids and
enzymatic dissolve bone matric
Breaking down bones
○
Needed to renew bones
○
-
Bone Cells and their Development
Osteogenic cell -> osteoblast -> osteocyte
-
Stem cells -> osteoclast
-
Anatomy of Whole Bone
Largest bone: femur
-
Dried bone
Epiphysis
○
Long part of bone: shaft, diaphysis
○
Growth of bone in length: metaphysis
○
-
Living bone
Cartilage
○
Periosteum: made up of two layers, outer fibrous layer,
inside layer of cells
○
Endosteum: incomplete cellular layer
○
-
Two Type of Bone
Compact
Osteon: tree-trunk, lamellae
○
Spaces like little spiders: osteocytes
Darker spots
§
○
-
Spongy: inside of flat bones (e.g. skull, scapula, clavicle, ribs)
Only ends of bone
○
-
Bone Formation
Ossification
-
Types: intramembranous and endochondral
-
Both begin in mesenchyme tissue of embryo
-
Basic process
Membrane of cartilage model
○
Mineralization of tissue
○
Ossification by osteoblasts - spongy the compact replaces
spongy at surface
○
-
Endochondrial Ossification
Start with cartilage model of bone; perichondrium
-
End with bone; periosteum
-
Growth in Width: (appositional)
Growth in Length at zones of Metaphysis
Epiphyseal Line, bones replace cartilage after puberty
Factors Affecting Bone Growth
Exercise
-
Nutrition
Vitamin D: normal absorption of calcium in intestines;
Rickets
Made in skin
§
○
Vitamin C: necessary for collagen synthesis; Scurvy
○
Vitamin A: necessary for synthesis of components of
bone matrix
○
-
Hormones
Human Growth Hormone from anterior pituitary gland in
brain; stimulates growth in length and width; stimulates
prechondrocytes to differentiate into chondrocytes in the
epiphyseal growth plate and cells in perichondrium
Giantism: excess prior to puberty
Cartilage continues to grow
□
§
Dwarfism: deficiency prior to puberty
§
Acromegaly: excess after puberty
§
○
Estrogen and Testosterone
Stimulates HGH production
§
Stimulates ossification of epiphyseal plate
§
○
Calcium
Levels are closely regulated
§
Homeostasis is maintained by hormones that affect
Bone storage
□
Digestion tract absorption
□
Kidney excretion
□
§
○
-
Osteopenia leads to Osteoporosis
Estrogen helps stimulate human growth hormone, after
menopause, estrogen levels decrease
More susceptible to fractures
○
-
Fractures
Breaks in bone
-
Named for severity, shape, position of break or physician who
first described them
-
Stages in Healing of a Bone Fracture
Hematoma formation (blood clot)1.
Soft callus formation2.
Hard callus formation3.
Bone remodeling4.
-
Week 2 - 4/2
Monday, April 2, 2018
3:30 PM
Skeletal System and
Articulations
Functions of Skeletal System
Support, protection
-
Movement with muscles
-
Blood cell production
-
Storage of minerals for other functions
-
Helps with pH balance
-
Absorbs contaminants from blood
-
What does the Skeletal System consist of?
Bones
-
Cartilage
-
Ligaments: connects bone to bone
-
Tendon: bone to muscle
-
Tissues
Connective tissue: bone (osseous), blood, fibrous, adipose
○
Nervous
○
-
Osseous (Bone) Tissue and Bonep
Bone Tissue Composition
Connective tissue with hard matric
-
Collagen fibers ---> flexibility and strength
-
Mineral salts including Ca3PO4 and CaCO3 deposit on
fibers ---> hardness and resists compression
Calcium
○
Phosphate
○
Carbonate
○
Organic compound: collagen
○
-
Bone Cells
Osteocyte: mature bone cell that maintains bone matric
-
Osteoblast: immature bone cell that secretes organic
components of matric
-
Osteoprogenitor cell: Stem cell whose divisions produce
osteoblasts
-
Osteoclasts: multinucleate cell that secretes acids and
enzymatic dissolve bone matric
Breaking down bones
○
Needed to renew bones
○
-
Bone Cells and their Development
Osteogenic cell -> osteoblast -> osteocyte
-
Stem cells -> osteoclast
-
Anatomy of Whole Bone
Largest bone: femur
-
Dried bone
Epiphysis
○
Long part of bone: shaft, diaphysis
○
Growth of bone in length: metaphysis
○
-
Living bone
Cartilage
○
Periosteum: made up of two layers, outer fibrous layer,
inside layer of cells
○
Endosteum: incomplete cellular layer
○
-
Two Type of Bone
Compact
Osteon: tree-trunk, lamellae
○
Spaces like little spiders: osteocytes
Darker spots
§
○
-
Spongy: inside of flat bones (e.g. skull, scapula, clavicle, ribs)
Only ends of bone
○
-
Bone Formation
Ossification
-
Types: intramembranous and endochondral
-
Both begin in mesenchyme tissue of embryo
-
Basic process
Membrane of cartilage model
○
Mineralization of tissue
○
Ossification by osteoblasts - spongy the compact replaces
spongy at surface
○
-
Endochondrial Ossification
Start with cartilage model of bone; perichondrium
-
End with bone; periosteum
-
Growth in Width: (appositional)
Growth in Length at zones of Metaphysis
Epiphyseal Line, bones replace cartilage after puberty
Factors Affecting Bone Growth
Exercise
-
Nutrition
Vitamin D: normal absorption of calcium in intestines;
Rickets
Made in skin
§
○
Vitamin C: necessary for collagen synthesis; Scurvy
○
Vitamin A: necessary for synthesis of components of
bone matrix
○
-
Hormones
Human Growth Hormone from anterior pituitary gland in
brain; stimulates growth in length and width; stimulates
prechondrocytes to differentiate into chondrocytes in the
epiphyseal growth plate and cells in perichondrium
Giantism: excess prior to puberty
Cartilage continues to grow
□
§
Dwarfism: deficiency prior to puberty
§
Acromegaly: excess after puberty
§
○
Estrogen and Testosterone
Stimulates HGH production
§
Stimulates ossification of epiphyseal plate
§
○
Calcium
Levels are closely regulated
§
Homeostasis is maintained by hormones that affect
Bone storage
□
Digestion tract absorption
□
Kidney excretion
□
§
○
-
Osteopenia leads to Osteoporosis
Estrogen helps stimulate human growth hormone, after
menopause, estrogen levels decrease
More susceptible to fractures
○
-
Fractures
Breaks in bone
-
Named for severity, shape, position of break or physician who
first described them
-
Stages in Healing of a Bone Fracture
Hematoma formation (blood clot)1.
Soft callus formation2.
Hard callus formation3.
Bone remodeling4.
-
Week 2 - 4/2
Monday, April 2, 2018 3:30 PM
Document Summary
Mineral salts including ca3po4 and caco3 deposit on fibers ---> hardness and resists compression fibers ---> hardness and resists compression. Osteocyte: mature bone cell that maintains bone matric. Osteoblast: immature bone cell that secretes organic components of matric. Osteoprogenitor cell: stem cell whose divisions produce osteoblasts. Osteoclasts: multinucleate cell that secretes acids and enzymatic dissolve bone matric. Periosteum: made up of two layers, outer fibrous layer, inside layer of cells. Spongy: inside of flat bones (e. g. skull, scapula, clavicle, ribs) Ossification by osteoblasts - spongy the compact replaces spongy at surface. Vitamin d: normal absorption of calcium in intestines; Vitamin a: necessary for synthesis of components of bone matrix. Human growth hormone from anterior pituitary gland in brain; stimulates growth in length and width; stimulates prechondrocytes to differentiate into chondrocytes in the epiphyseal growth plate and cells in perichondrium. Estrogen helps stimulate human growth hormone, after menopause, estrogen levels decrease.
