Functions of Bones

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Shara M. Marshall, M.S.
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ANATOMICAL REGIONS, POSITIONS AND TERMINOLOGY
Overview
• Anatomy:
• Physiology:
Principle of Complementarity
• Anatomy and physiology are inseparable.
•
•
Levels of Structural Organization
• Chemical:
• Cellular:
• Tissue:
• Organ:
• Organ system:
• Organismal:
Overview of Organ Systems
• The integumentary system functions to:
• The skeletal system functions to:
• The muscular system functions to:
• The nervous system functions to:
• The endocrine system functions to:
• The cardiovascular system functions to:
• The lymphatic system functions to:
• The respiratory system functions to:
• The digestive system functions to:
• The urinary system functions to:
• The reproductive system functions to:
2
Survival Needs
1.Nutrients
•
•
2.Oxygen
•
3.Water
•
•
4.Normal body temperature
•
5.Appropriate atmospheric pressure
•
Homeostasis
• Definition:
•
Components of a Homeostatic Control Mechanism
•
•
Components of a Control Mechanism (contain at least the following three components)
1.Receptor (sensor)
•
•
2.Control center
•
•
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3.Effector
•
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Negative Feedback
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• Example: Regulation of body temperature
Positive Feedback
•
•
• Example:
• Enhancement of labor contractions by oxytocin
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Anatomical Position
• Standard anatomical body position:
•
•
•
Regional Terms
• Regional terms:
Directional Terms
 Superior (cranial)  Inferior (caudal)  Ventral (anterior)  Dorsal (posterior) Medial Lateral Intermediate Proximal –
 Distal  Superficial DeepBody Planes and Sections
• Sagittal plane
•
•
• Midsagittal (median) plane
•
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• Parasagittal plane
•
• Frontal (coronal) plane
•
• Transverse (horizontal) plane
•
Body Cavities
Two Large Cavities:
• Dorsal cavity
• Two subdivisions:
• Cranial cavity
• Encases:
•
Vertebral cavity
• Encases:
• Ventral cavity
• Houses:
• Two subdivisions (separated by diaphragm):
•
•
• Thoracic cavity subdivisions:
• Two pleural cavities
• Each one houses:
•
Mediastinum
• Contains:
• Also contains:
•
Pericardial cavity
• Encloses:
• Abdominopelvic cavity subdivisions:
• Abdominal cavity
• Contains:
•
Pelvic cavity
•
Contains:
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Abdominopelvic Regions
• Nine divisions used primarily by anatomists
Matter
• Definition:
• States of matter:
1. Solid2. Liquid3. Gas-
Energy
• Definition:
• Types of energy:
• Kinetic—
• Potential• Electrical—
• Energy may be converted from one form to another, but conversion is inefficient.
Composition of Matter
• Elements • AtomsAtomic Structure
• Neutrons
•
• Mass =
• Protons
•
• Mass =
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• Electrons
•
•
Mass =
•
Identifying Elements
• Atoms of different elements contain different numbers of subatomic particles
• Compare hydrogen, helium and lithium
• Atomic number =
• Mass number =
•
• Isotopes =
Molecules and Compounds
•
Most atoms combine chemically with other atoms to form molecules and compounds
•
•
Molecule—
(e.g., H2 or C6H12O6)
Compound—
(e.g., C6H12O6)
Chemical Bonds
•
• Octet rule:
Chemically Inert Elements
•
•
Chemically Reactive Elements
•
•
Types of Chemical Bonds (Ionic, Covalent, Hydrogen)
Ionic Bonds
• Ions are formed by transfer of valence shell electrons between atoms
• Anions (– charge):
• Cations (+ charge):
• Attraction of opposite charges results in:
Covalent Bonds
• Formed by sharing of two or more valence shell electrons
•
• Sharing of electrons may be equal or unequal
• Equal sharing produces:
• CO2
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• Unequal sharing by atoms with different electron-attracting abilities produces:
• H 2O
• Atoms with six or seven valence shell electrons are electronegative, e.g., oxygen
Hydrogen Bonds
• Attractive force between electropositive hydrogen of one molecule and an electronegative atom of another molecule
Chemical Reactions
Synthesis Reactions
• A + B  AB
•
•
•
Decomposition Reactions
• AB  A + B
•
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•
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Classes of Compounds
• Inorganic compounds
• Do not contain:
• Organic compounds
•Contain:
(ex’s. water, salts, and many acids and bases)
(ex’s. carbohydrates, fats, proteins, nucleic acids)
Water
•
•
Salts
• Ionic compounds that dissociate in water
•
Acids and Bases
•
Both are electrolytes
•
Acids -
• HCl  H+ + Cl–
• Bases• NaOH  Na+ + OH–
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Acid-Base Concentration
• Acid solutions contain [H+]
• As [H+] increases:
• Basic solutions contain bases (e.g., OH–)
• As [H+] decreases (or as [OH–] increases):
pH:
• Neutral solutions:
•
•
pH =
• Acidic solutions
• pH =
•
•
• Basic solutions
• pH=
•
For all of the following organic compounds, they are formed by a process called dehydration synthesis and broken down by a
process called hydrolysis and the atoms of these organic macromolecules are chemically bound by covalent bonds.
**Carbohydrates
•
• Three classes
• Monosaccharides•
Disaccharides-
•
Polysaccharides-
• Functions
• Primary role:
•
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**Lipids
•
• Main types:
• Triglycerides
• Phospholipids
• Steroids
*Triglycerides
• Defined as:
• Composed of:
• Main functions
•
•
•
*Phospholipids
• Modified triglycerides:
•
• “Head” and “tail” regions:
•
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*Steroids
• Steroids—
• Ex’s. -Cholesterol, vitamin D, steroid hormones, and bile salts
**Proteins
• Composed of:
• After amino acids are linked together:
• This folding process results in four different levels of protein structure:
• The quaternary structure:
• Proteins like enzymes and hemoglobin are considered functional because:
Protein Denaturation
• Definition:
• A denatured protein is:
Enzymes
• Biological catalysts
• Function:
**Nucleic Acids
• DNA and RNA
•
• Building block =
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Deoxyribonucleic Acid (DNA)
• Four bases:
• adenine (A), guanine (G), cytosine (C), and thymine (T)
•
•
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Ribonucleic Acid (RNA)
• Four bases:
• adenine (A), guanine (G), cytosine (C), and uracil (U)
•
• Three varieties of RNA carry out the DNA orders for protein synthesis
•
Adenosine Triphosphate (ATP)
•
• Function:
• Phosphorylation:
•
Generalized Cell
•
•
All cells have some common structures and functions
Human cells have three basic parts:
•
•
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Plasma membrane—
Cytoplasm—
Nucleus—
The Plasma Membrane is a bimolecular layer of phospholipids and proteins and plays a dynamic role in cellular activity:
•The plasma membrane separates:
•The plasma membrane is semi-permeable which means that:
Types of Membrane Transport
• Passive Transport
•
•
Substance moves:
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• Active Transport
•
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Substances are moved/”pumped”:
Passive Transport
• What determines whether or not a substance can passively permeate (cross) a membrane?
1.
2.
Passive Transport
• Simple diffusion
• Facilitated diffusion
• Osmosis
Passive Transport: Simple Diffusion
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Passive Transport: Facilitated Diffusion
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•
Passive Transport: Osmosis
•
• Water diffuses through plasma membranes:
•
•
Through the lipid bilayer
Through water channels called aquaporins (AQPs)
Passive Transport: Osmosis
•Osmolarity:
•When solutions of different osmolarity are separated by a membrane:
Importance of Osmosis
•When osmosis occurs:
•A change in cell volume:
Tonicity
•Defined as:
•Isotonic:
•Hypertonic:
•Hypotonic:
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Active Transport
 The Sodium-potassium pump (Na+-K+ ATPase) is a specific example of active transport
o
o
Vesicular Transport
 Transports:


Two main types:
o Exocytosis –
o
Endocytosis -
Other organelles:


Membranous structures
o Nucleus with chromatino
Mitochondria –
o
Endoplasmic Reticulum (ER) (rough and smooth) –
o
Golgi Apparatus-
o
Lysosomes-
Non-membranous structures
o Centrioles –
o

Cytoskeleton
 Elaborate series of protein containing rod-like filaments throughout the cytoplasm; made up of:

Extensions of the plasma membrane
o Cilia are –
o
Flagella are –
o
Microvilli are -
The Cell Cycle
• Includes:
• Interphase
•
•Three Subphases:
•Gap 1 (G1)•Synthesis Phase (S phase)•Gap 1 (G2)•Cell Division (mitotic phase or mitosis)
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DNA Replication
• Helicase:
• Each nucleotide strand:
•DNA polymerase:
• End result:
•This process is called:
Cell Division
•
•
•Does not occur in most mature cells of nervous tissue, skeletal and cardiac muscle
•Includes two distinct events
1. Mitosis—four stages of nuclear division:
• Prophase -
• Metaphase • Anaphase • Telophase •
Cytokinesis -
Protein Synthesis
• DNA is:
• Gene:
• Each triplet specifies:
Roles of the Three Main Types of RNA
• Messenger RNA (mRNA)
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• Ribosomal RNA (rRNA)
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• Transfer RNAs (tRNAs)
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Transcription
•
• Transcription factor
•
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•RNA polymerase
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Translation
• Converts:
• Involves:
Genetic Code
• Each three-base sequence on DNA is represented by a codon
• Codon—
Steps of Translation
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
 There are four tissue types in the body
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Epithelial tissue
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Connective tissue
•
Muscle tissue
•
Nerve tissue
Characteristics of Epithelial Tissue
1.Cells have polarity—
•
•
2.Are composed of closely packed cells
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3.Avascular

4.High rate of regeneration

Classification of Epithelia
• Ask two questions:
1. How many layers?
1=
>1 =
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•
What type of cell?
•
(If stratified, name according to apical layer of cells)
• Squamous
• Cuboidal
• Columnar
Overview of Epithelial Tissues
Epithelia: Simple Squamous
* Description:
* Function:
* Location:
Epithelia: Simple Cuboidal
* Description:
* Function:
* Location:
Epithelia: Simple Columnar
* Description:
* Function:
* Location:
Epithelia: Pseudostratified Columnar Epithelium
* Description:
* Function:
* Location:
Epithelia: Stratified Squamous
* Description:
* Function:
* Location:
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Epithelia: Stratified Cuboidal and Columnar Epithelium
* Description:
* Function:
* Location:
Epithelia: Transitional Epithelium
* Description:
* Function:
* Location:
Glandular Epithelia
 Gland:

Two major types:
o Endocrine glandso
o Exocrine glands-
Connective Tissue
• Most abundant and widely distributed tissue type
• Four classes
*
*
*
*
Connective tissue proper
Cartilage
Bone tissue
Blood
Characteristics of Connective Tissue
• Connective tissues have:
*
* Cells separated by nonliving extracellular matrix (ground substance and fibers)
Extracellular Matrix
• Ground substance
• Components
•
•
Fibers (three types)
• Collagen
•
• Elastic
•
• Reticular
•
•Cells of Connective Tissue
•“blasts” = Mitotically active and secretory cells
•“cytes” = Mature cells
•Fibroblasts in connective tissue proper
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•Chondroblasts and chondrocytes in cartilage
•Osteoblasts and osteocytes in bone
•Hematopoietic stem cells in bone marrow
Overview of Connective Tissues
• Connective Tissues: Osseous
* Description:
* Function:
* Location:
• Connective Tissues: Cartilage
* Description:
* Function:
* Location:
• Connective Tissues: Dense Connective Tissue
* Description:
* Function:
* Location:
• Connective Tissues: Areolar Connective Tissue
* Description:
* Function:
* Location:
• Connective Tissues: Adipose Connective Tissue
* Description:
* Function:
* Location:
• Connective Tissues: Reticular Connective Tissue
* Description:
* Function:
* Location:
• Connective Tissues: Blood
* Description:
* Function:
* Location:
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Muscle Tissue (Three Types)
• Skeletal Muscle
* Description:
* Function:
* Location:
• Cardiac Muscle
* Description:
* Function:
* Location:
• Smooth muscle
* Description:
* Function:
* Location:
Nervous Tissue
* Description:
* Function:
* Location:
Steps in Wound Repair
•
Inflammation
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Organization and restored blood supply
•
Regeneration and fibrosis
Epithelial Membranes
• Cutaneous membrane (skin)
• Mucous membranes
• Mucosae
•
• Serous Membranes
• Serosae—membranes lining the closed ventral body cavity
• Parietal serosae • Visceral serosae –
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(e.g., digestive and respiratory tracts)
•
Serosa are named based on their location:
•Pleural membranes surround:
•Pericardial membranes surround:
•Peritoneal membranes surround:
Skin (Integument)
•
Consists of three major regions
1.
2.
3.
Epidermis—
Dermis—
Hypodermis (superficial fascia)—
•
Epidermis
•
•
Cells of epidermis
• Keratinocytes—
• Melanocytes
•
Layers of the Epidermis: Stratum Basale (Basal Layer)
•
• Also called stratum germinativum:
• Cells travel from basal layer to surface
• Takes 25–45 days
Layers of the Epidermis: Stratum Spinosum (Prickly Layer)
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Layers of the Epidermis: Stratum Granulosum (Granular Layer)
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Layers of the Epidermis: Stratum Lucidum (Clear Layer)
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Layers of the Epidermis: Stratum Corneum (Horny Layer)
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• Functions
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Dermis
•
• Two layers:
• Papillary
• Reticular
Layers of the Dermis: Papillary Layer
• Papillary layer
•
• Contains dermal papillae with:
•
•
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Layers of the Dermis: Reticular Layer
• Reticular layer
•
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Skin Color
• Three pigments contribute to skin color:
1. Melanin
•
•
2. Carotene
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3. Hemoglobin
•
Appendages of the Skin
• Derived from the epidermis
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Sweat Glands
• Two main types of sweat (sudoriferous) glands
1. Eccrine sweat glands— abundant on palms, soles, and forehead
• Sweat:
•
•
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2. Apocrine sweat glands—confined to:
• Sebum:
•
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Sebaceous (Oil) Glands
•
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• Sebum
•
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Hair
• Functions
•
•
• Consists of:
•
• Three layers from interior to exterior:
• Hair pigments:
Hair Follicle
• Two-layered wall:
• Hair bulb:
• Hair follicle receptor (root hair plexus):
•
• Arrector pili
•
•
Structure of a Nail
•
•Structures of the nail:
•
Functions of the Integumentary System
1.Protection—
• Chemical
•
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•
Physical/mechanical barriers
•
Biological barriers
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2.Body temperature regulation
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3.Cutaneous sensations
•
4.Metabolic functions
•
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5.Blood reservoir—
6.Excretion—
Skin Cancer
• Three major types:
• Basal cell carcinoma
• Squamous cell carcinoma
• Melanoma
Basal Cell Carcinoma
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Squamous Cell Carcinoma
•
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Melanoma
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Melanoma
• Characteristics (ABCDE rule)
A: AsymmetryB: BorderC: Color-
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D: DiameterE: EvolutionPartial-Thickness Burns
• First degree
•
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• Second degree
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Full-Thickness Burns
• Third degree
•
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Severity of Burns
• Critical if:
•
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•
Bones: An Overview
Functions of Bones
• Support
•
• Protection
•
• Movement
•
• Storage
•
• Blood cell formation (hematopoiesis) in:
•
Classification of Bones by Shape
• Long bones
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•
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• Short bones
•
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• Flat bones
•
• Examples:
• Irregular bones
•
• Examples:
Bone Markings (Refer to Table 5.1)
• Bulges, depressions, and holes serve as
•
•
•
Bone Markings: Projections
•
Sites of muscle and ligament attachment
• Tuberosity—rounded projection
• Crest—narrow, prominent ridge
• Trochanter—large, blunt, irregular surface
• Line—narrow ridge of bone
• Tubercle—small rounded projection
• Epicondyle—raised area above a condyle
• Spine—sharp, slender projection
Process—any bony prominence
•
Projections that help to form joints
•
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Head - bony expansion carried on a narrow neck
Facet - smooth, nearly flat articular surface
Condyle - rounded articular projection
Ramus -armlike bar
Bone Markings: Depressions and Openings
• Meatus -canal-like passageway
• Sinus - cavity within a bone
• Fossa -shallow, basinlike depression
• Groove- furrow
• Fissure -farrow, slitlike opening
• Foramen -round or oval opening through a bone
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Bone Textures
• Compact bone
•
•
•
Spongy bone
•
Membranes of Bones
 Periosteum (fibrous connective tissue)

o
Surrounds:
o
Contains:
o
Secured to compact bone by:
Endosteum (areolar CT)
o
Structure of a Long Bone
• Diaphysis (shaft)
•
• Epiphyses
•
•
•
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Structure of Short, Irregular, and Flat Bones
•
“think of a stiffened spongy bone sandwich”
Microscopic Anatomy of Bone: Compact Bone
• Haversian system, or osteon—structural unit
• Lamellae
•
•
• Central (Haversian) canal
•
• Perforating (Volkmann’s) canals
•
•
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• Lacunae—
• Canaliculi—
Microscopic Anatomy of Bone: Spongy Bone
•
•
•
Chemical Composition of Bone: Organic
• Bone cells: osteoblasts, osteocytes, osteoclasts
• Osteoid—organic bone matrix secreted by osteoblasts
•
•
Chemical Composition of Bone: Inorganic
• Hydroxyapatites (mineral salts)
•
•
•
Bone Formation, Growth and Remodeling
• Ossification—
• Stages
• Bone formation—
• Postnatal bone growth—
• Bone remodeling and repair—
Growth in Length of Long Bones
• Interstitial growth:
•
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Growth in Width of All Bones
• Appositional growth:
•
Control of Remodeling
• What controls continual remodeling of bone?
•
•
Hormonal Control of Blood Ca2+
•
Primarily controlled by parathyroid hormone (PTH)
 Blood Ca2+ levels

__________________________

PTH stimulates osteoclasts to degrade bone matrix and release Ca 2+

____________________________________
Response to Mechanical Stress
•
•
•
Curved bones are thickest where they are most likely to buckle
Trabeculae form along lines of stress
Large, bony projections occur where heavy, active muscles attach
Stages in the Healing of a Bone Fracture
1.Hematoma forms
•
•
2. The break is splinted by a fibrocartilage callus
•
•
•
•
3.Bony callus formation
•
•
4.Bone remodeling
•
•
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The Axial Skeleton
• Three major regions
• Skull and associated bones
• Vertebral column
• Thoracic cage
The Skull
• Two sets of bones
1. Cranial bones
• Enclose the brain in the cranial cavity
• Cranium consists of:
• Cranial base:
2. Facial bones
• Cavities for:
• All skull bones are joined by:
• Facial bones provide sties of attachment for:
Cranial Bones
• Frontal bone
• Parietal bones (2)
• Occipital bone
• Temporal bones (2)
• Sphenoid bone
• Ethmoid bone
Frontal Bone
•
•
Parietal Bones and Major Associated Sutures
•
•
Four sutures mark the articulations of parietal bones with frontal, occipital, and temporal bones:
1. Coronal suture—
2. Sagittal suture—
3. Lambdoid suture—
4. Squamous (squamosal) sutures—
Occipital Bone
•
•
• Contains:
Temporal Bones
• Inferior to parietal bones
• External acoustic canal:
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• Zygomatic process:
• Mastoid process:
• Styloid process:
• Mandibular fossa:
Sphenoid Bone
•
• Three pairs of processes:
• Contains the:
Ethmoid Bone
• Superior part of :
• Contains:
Facial Bones
• Mandible
• Maxillary bones (maxillae) (2)
• Zygomatic bones (2)
• Nasal bones (2)
• Lacrimal bones (2)
• Palatine bones (2)
• Vomer
• Inferior nasal conchae (2)
Mandible
•
•
• Temporomandibular joint:
• Mandibular condyle articulates w:
Maxillary Bones
•
•
Zygomatic Bones
•
•
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Nasal Bones and Lacrimal Bones
• Nasal bones
• Form:
• Lacrimal bones
•
• Lacrimal fossa houses:
Palatine Bones and Vomer
• Palatine bones
•
•
Vomer
•
Inferior Nasal Conchae
• Form part of lateral walls of nasal cavity
Orbits
• Encase:
• Sites of attachment for:
• Formed by:
•
Hyoid Bone
•
•
• Site of attachment for:
Vertebral Column
•
•
•
Flexible curved structure containing 26 irregular bones (vertebrae)
•
•
•
•
•
Cervical vertebrae (7)—vertebrae of:
Thoracic vertebrae (12)—vertebrae of:
Lumbar vertebrae (5)—vertebra of:
Sacrum—bone inferior to:
Coccyx—terminus of vertebral column
Vertebral Column: Curvatures
• Increase the resilience and flexibility of the spine
•
Primary curvatures
•
•
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•
•
Secondary curvatures
•
•
Abnormal spine curvatures
•
•
•
Scoliosis (abnormal lateral curve)
Kyphosis (hunchback)
Lordosis (swayback)
General Structure of Vertebrae
• Body or centrum
•
•
•
Vertebral arch
•
Formed from:
Vertebral foramen
•
• Seven processes per vertebra:
• Spinous process—
• Transverse processes (2)—
• Superior articular processes (2)—
• Inferior articular processes (2)—
Cervical Vertebrae
• C1 to C7:
• C3 to C7 share the following features
•
•
• Transverse foramen in:
• C1 (atlas) and C2 (axis) have unique features
• Atlas (C1)
•
• Consists of:
• Superior articular facets articulate with:
• Axis (C2)
•
•
Thoracic Vertebrae
• T1 to T12
•
•
•
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Lumbar Vertebrae
• L1 to L5
•
•
•
Sacrum and Coccyx
• Sacrum
•
•
•
•
5 fused vertebrae (S1–S5)
Forms:
Articulates with:
Coccyx
•
•
•
Tailbone
3–5 fused vertebrae
Articulates superiorly with:
Thoracic Cage
• Composed of
•
•
•
Thoracic vertebrae
Sternum
Ribs and their costal cartilages
Sternum (Breastbone)
• Three fused bones
•
Manubrium
•
Body
•
Xiphoid process
•
•
•
•
Ribs and Their Attachments
• 12 pairs
•
• Pairs 1 through 7
• True ribs
•
Attach directly to the sternum by individual costal cartilages
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• Pairs 8 through 10
• False ribs
•
• Pairs 11-12
• Floating ribs
•
Appendicular Skeleton
• Bones of the limbs and their girdles
• Pectoral girdle attaches the upper limbs to the body trunk
• Pelvic girdle secures the lower limbs
Pectoral Girdle (Shoulder Girdle)
• Clavicles and the scapulae
• Attach:
• Provide:
Clavicles (Collarbones)
•
•
•
Scapulae (Shoulder Blades)
•
•
•
The Upper Limb
• 30 bones form the skeletal framework of each upper limb
•
Arm
•
Forearm
•
Hand
•
•
• 8 carpal bones in the wrist
• 5 metacarpal bones in the palm
• 14 phalanges in the fingers
Humerus
•
• Head of Humerus Articulates with:
• Contains:
• Articulates inferiorly with the radius and ulna via the:
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Bones of the Forearm
• Ulna
•
•
•
•
•
Forms:
Contains:
Contains:
Radius
•
•
•
•
Head articulates with:
Contains:
Interosseous membrane connects:
Hand: Carpus
• Eight bones in two rows
• Proximal row
•
• Distal row
•
• Only scaphoid and lunate articulate with radius to form wrist joint
Hand: Metacarpus and Phalanges
• Metacarpus
•
• Phalanges
• Each finger (digit), except the thumb, has:
•
•
Pelvic (Hip) Girdle
• Two hip bones (each also called coxal bone or os coxae)
•
•
•
•
•
Attach:
Support: pelvic organs
Hip Bone Each hip bone consists of three fused bones: ilium, ischium, and pubis
Three regions
1. Ilium
•
•
2. Ischium
•
3. Pubis
•
•
36
Comparison of Male and Female Pelves
• Female pelvis
• Adapted for:
• True pelvis:
• Cavity of the true pelvis is broad, shallow, and has greater capacity
• Male pelvis
•
•
•
The Lower Limb
•
•
• Three segments of the lower limb
• Thigh:
• Leg:
• Foot: 7 tarsal bones in the ankle, 5 metatarsal bones in the metatarsus, and 14 phalanges in the toes
Femur
•
• Articulates:
• Contains:
Bones of the Leg
• Tibia
•
•
•
Fibula
•
•
•
•
Connected to tibia by:
Articulates:
Foot: Tarsals
•
•
• Tarsal bones: calcaneus, talus, cuboid, navicular, and the medial, intermediate, and lateral cuneiforms
Foot: Metatarsals and Phalanges
• Metatarsals:
•
•
•
Phalanges
•
•
•
Each digit (except the hallux) has three phalanges
37
Joints (Articulations)
• Articulation—
• Functions of joints:
•
•
Functional Classification of Joints
•
• Three functional classifications:
• Synarthroses—
• Amphiarthroses—
• Diarthroses—
Structural Classification of Joints
•
• Three structural classifications:
• Fibrous (As a general rule, these are immovable)
• Cartilaginous (Both movable and immovable, most are amphiarthroses)
• Synovial (All are freely movable)
Fibrous Joints
•
•
• Three types:
• Sutures
• Syndesmoses
Fibrous Joints: Sutures
•
•
•
Fibrous Joints: Syndesmoses
•
•
• Examples:
• distal tibiofibular joint
Cartilaginous Joints
•
•
Examples, Symphyses (pubic symphysis, intervertebral discs)
38
Synovial Joints
•
•
Four Distinguishing features:
1.Articular Cartilage2.Articular Capsule3. Joint cavity-
•
Encloses synovial fluid
4. Reinforcing Ligaments
•
Synovial Joints: Friction-Reducing Structures
• Bursae:
•
• Contain:
• Commonly act as “ball bearings” where ligaments, muscles, skin, tendons, or bones rub together
• Tendon sheath:
•
Classification of Synovial Joints
• Six types, based on shape of articular surfaces:
• Plane
• Hinge
• Pivot
• Condyloid
• Saddle
• Ball and socket
Plane Joints
•
•
•
Hinge Joints
•
•
•
Pivot Joints
•
•
39
Condyloid Joints
•
•
•
Saddle Joints
•
•
•
Ball-and-Socket Joints
•
•
Chapter 6-The Muscular System
Three Types of Muscle Tissue
1.Skeletal muscle tissue:
•
•
•
•
2.Cardiac muscle tissue:
•
•
•
3.Smooth muscle tissue:
•
•
•
Muscle Functions
1.
2.
3.
4.
Skeletal Muscle
• Each muscle is served by one artery, one nerve, and one or more veins
•
Connective tissue sheaths of skeletal muscle:
• Epimysium:
• Perimysium:
• Endomysium:
40
Skeletal Muscle: Attachments
• Muscles attach:
• Directly—
•
Indirectly—
Microscopic Anatomy of a Skeletal Muscle Fiber
•
•
•
Myofibrils
•
•
• Exhibit striations:
Sarcomere
•
•
•
Features of a Sarcomere
• Thick filaments:
• Thin filaments:
• Z disc:
• H zone:
• M line:
Ultrastructure of Thick Filament
• Composed of the protein myosin
• Myosin tails
• Myosin heads:
•
•
Ultrastructure of Thin Filament
• Twisted double strand of actin (protein)
•
Sarcoplasmic Reticulum (SR)
 Network of:

Stores:
T (transverse) Tubules:
 Continuous with:

Penetrate cells interior at each:
o T tubules:
41
Sliding Filament Theory
• In the relaxed state:
• During contraction:
• As H zones shorten and disappear:
The Neuromuscular Junction
• Axons of motor neurons:
• Each axon:
• Each axon ending forms:
• Axon terminal and muscle fiber are:
• Synaptic vesicles of axon terminal contain:
• Junctional folds of the sarcolemma contain:
• A nerve impulse:
• Ach is:
Events at the Neuromuscular Junction
1. A nerve impulse:
2. Ca2+:
3. Ca2+ entry causes:
4. Ach diffuses:
5. Ach binding:
6. Na+:
7. Once threshold is reached:
The Action Potential
•The AP is:
•Repolarization:
42
Destruction of Acetylcholine
• ACh effects are quickly terminated by:
• Prevents:
Role of Calcium (Ca2+) in Contraction
• At low intracellular Ca2+ concentration:
•
•
•
• At higher intracellular Ca2+ concentrations:
•
•
•
•
Cross Bridge Cycle
•
Continues as long as:
•
Cross bridge formation:
•
Power stroke:
•
Cross bridge detachment:
•
“Cocking” of the myosin head:
43
Motor Unit: The Nerve-Muscle Functional Unit
• Motor unit =
Graded Muscle Responses
 Defined:
1. Changing:
2. Changing:
Response to Change in Stimulus Frequency
• A single stimulus results in a single contractile response called a:
• Increase frequency of stimulus
• Ca2+ release stimulates further contraction 
• Further increase in stimulus frequency 
• If stimuli are given quickly enough, 
Muscle Metabolism: Energy for Contraction
•
•
• ATP is regenerated by:
• Direct phosphorylation of ADP by creatine phosphate (CP)
• Anaerobic pathway
• Aerobic respiration
•Direct phosphorylation of ADP by creatine phosphate (CP)
•
•
•
•
CP is:
When ATP stores are depleted:
Products are:
Provides energy for:
•Anaerobic Pathway
• Under intense muscle activity or when oxygen delivery is impaired:
• Begins just like aerobic pathway (glycolysis) but pyruvic acid is:
• Products are:
• Provides energy for:
44
•Aerobic Pathway
• Produces:
• Fuels:
• Products are:
• Provides energy for:
Muscle Fatigue
• Defined:
• Results from:
•
•
•
Skeletal Muscles: Functional Groups
 Antagonists
o
 Synergists
o
Naming Skeletal Muscles
 Location—bone or body region associated with the muscle
 Shape—e.g., deltoid muscle (deltoid = triangle)
 Relative size—e.g., maximus (largest), minimus (smallest), longus (long)
 Direction of fibers or fascicles—e.g., rectus (fibers run straight), transversus, and oblique (fibers run at angles to an
imaginary defined axis)
 Naming Skeletal Muscles
 Number of origins—e.g., biceps (2 origins) and triceps (3 origins)
 Location of attachments—named according to point of origin or insertion
 Action—e.g., flexor or extensor, muscles that flex or extend, respectively
Muscles of Facial Expression
 Frontalis
o
 Orbicularis Oculi
o
 Orbicularis Oris
o
 Buccinator
o
 Zygomaticus
o
 Platysma
o
Muscles of Mastication
 Temporalis
o Prime movers of jaw closure
 Masseter
o
45
Muscles of the Neck
 Sternocleidomastoid
o
Trunk Muscles
 Pectoralis Major
o
 Rectus Abdominis
o
 External oblique
o
Neck/Trunk/Shoulder Muscles
 Posterior muscles
o Trapezius

o Latissimus Dorsi

o Erector Spinae

o Deltoid

Arm/Shoulder Muscles
 Anterior Rlexor muscles
o Brachialis and biceps brachii

o Brachioradialis

o Deltoid

 Posterior Extensor muscles
o Triceps brachii

Muscles of the Forearm
 Actions:

Most anterior muscles are :

Most posterior muscles are :
Hip/Thigh Leg Muscles
 Iliopsoas and Sartorius
o


Lateral thigh:
o Gluteus Maximus

o Gluteus Medius

Medial thigh:
o Adductor Muscles
46

Hamstrings (Biceps Femoris, Semitendinosus, Semimembranosus)
o

Quadriceps Group (Vastus Medialis, Lateralis, intermedius and rectus femoris)
o
Muscles of the Anterior Compartment of the Lower Leg
 Tibialis anterior and Extensor digitorum longus
o
Muscles of the Lateral Compartment of the Lower Leg
 Fibularis longus
o
Muscles of the Posterior Compartment of the Lower Leg
 Gastrocnemius and Soleus
o
o
The Eye and Vision
•
•
•
Accessory Structures of the Eye
• Protect the eye and aid eye function
•
•
•
•
•
Eyebrows
Eyelids (palpebrae)
Conjunctiva
Lacrimal apparatus
Extrinsic eye muscles
Eyebrows
•
• Function in
•
•
Eyelids
•
• Palpebral fissure—
• Medial and Lateral Canthi• Caruncle—
• Tarsal plates—
• Levator palpebrae superioris—
47
• Eyelashes
•
• Lubricating glands associated with the eyelids
•
Tarsal glands-
Conjunctiva
• Mucous membranes of the eye
•
Palpebral conjunctiva:
•
Bulbar conjunctiva:
Lacrimal Apparatus
• Consists of: Lacrimal gland and ducts that connect to nasal cavity
• Releases: Lacrimal secretion (tears)
• The solution also contains:
• Blinking spreads the tears towards the:
Extrinsic Eye Muscles
• The movement of the eye is controlled by six muscles on the external surface of each eye:
• Superior rectus:
• Inferior rectus:
•
• Lateral rectus:
• Medial rectus:
• Inferior oblique:
• Superior oblique:
• The innervations to each muscle can be remembered by the following equation: (LR 6SO4)O3
• Which means:
• Lateral rectus:
• Superior oblique:
• All others:
Structure of the Eyeball
• Wall of eyeball contains three layers
•
•
•
Fibrous
Vascular
Sensory
48
Fibrous Layer
•
• Two regions: sclera and cornea
1.Sclera
•
•
•
Fibrous Layer
2. Cornea:
•
•
Vascular Layer
• Middle pigmented layer
• Three regions: choroid, ciliary body, and iris
1. Choroid region
•
•
•
2. Ciliary body
•
•
•
3. Iris
• The colored part of the eye
• Pupil—
• Close vision and bright light—
• Distant vision and dim light—
Sensory Layer: Retina
• Delicate two-layered membrane
•
Pigmented layer –
•
Neural layer -
The Retina
• Ganglion cell axons
•
•
• Optic disc (blind spot)
•
•
49
Photoreceptors
• Rods
•
•
•
More numerous at:
Operate in:
Provide:
• Cones
•
•
•
Found in:
Operate in:
Provide:
Cones
• There are three types of cones named for the colors of light absorbed:
• Intermediate hues are perceived by:
• Color blindness is due to:
Blood Supply to the Retina
• Two sources of blood supply
•
Choroid supplies:
•
Central artery and vein of the retina supply:
Internal Chambers and Fluids
• The lens and ciliary zonule separate the anterior and posterior segments
•
Posterior segment contains vitreous humor that:
•
Anterior segment is composed of two chambers
• Anterior chamber—
•
•
•
• Posterior chamber—
•
Anterior segment contains aqueous humor
•
• Supplies:
•
Glaucoma:
Lens
•
•
•
•
•
Lens fibers—
Lens becomes denser, more convex, and less elastic with age
Cataracts (clouding of lens) occur as a consequence of aging, diabetes mellitus, heavy smoking, and frequent exposure to
intense sunlight
50
Light
• Our eyes respond to:
• Light:
• Rods and Cones respond to:
Refraction and Lenses
• Refraction
•
•
Occurs when light meets the surface of a different medium at an oblique angle
Refraction and Lenses
• Light passing through a convex lens is:
• The image formed at the focal point is:
Focusing Light on the Retina
• Pathway of light entering the eye: cornea, aqueous humor, lens, vitreous humor, neural layer of retina, photoreceptors
• Light is refracted
•
•
•
•
Change in lens curvature allows for fine focusing of an image
Focusing for Distant Vision
• Light rays from distant objects are:
• Ciliary muscles are:
• Lens is:
Focusing for Close Vision
• Light from a close object diverges as it approaches the eye; requires that the eye make active adjustments
• Close vision requires
•
•
Accommodation—
• Near point of vision is determined by:
• Presbyopia—
Constriction—
•
Convergence—
Problems of Refraction
• Myopia (nearsightedness)—
•
Hyperopia (farsightedness)—
51
Functional Anatomy of Photoreceptors
• Rods and cones
•
Outer segment of each contains visual pigments -
•
Inner segment of each joins the:
Visual Pathway
•
•
•
•
The Ear: Hearing
• Three parts of the ear
1. External (outer) ear
2. Middle ear (tympanic cavity)
3. Internal (inner) ear
The Ear: Hearing and Balance
• External ear and middle ear are involved with:
• Internal ear (labyrinth) functions in both:
External Ear
• The auricle (pinna) is composed of:
•
•
• External acoustic meatus (auditory canal)
•
• Tympanic membrane (eardrum)
•
•
•
Middle Ear
• Pharyngotympanic (auditory) tube—connects the middle ear to the nasopharynx
•
Ear Ossicles
• Three small bones in tympanic cavity: the malleus, incus, and stapes
•
•
Transmit :
Tensor tympani and stapedius muscles :
52
Internal Ear
• Bony labyrinth
•
•
Three parts:
• Filled with:
•
•
Filled with:
Vestibule
•
2.Contains two membranous sacs (saccule and utricle) that:
•
•
Semicircular Canals
• Three canals that:
• Membranous semicircular ducts:
• Ampulla (swelling) of each canal houses:
• Receptors respond to:
The Cochlea
• A spiral, conical, bony chamber
•
•
•
Contains the cochlear duct:
Transmission of Sound to the Internal Ear
•
•
•
Auditory Pathways to the Brain
• Impulses from the cochlea pass:
•
•
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