Test Prep #2
Chapter 4: Tissues
*Tissues are group of cells similar in structure working together to perform a common
Function. Four types of Tissue: 1. Connective Tissue 2) Epithelial Tissue 3) Muscle Tissue
4) Nervous Tissue.
*Epithelial tissue covers exposed surfaces (skin), lines internal passageways and forms glands.
*Apical Surface: They are always on top.
-Goblet Cells: A unicellular gland for secretions (Mucus)
-Cilia: To move substances
-Microvilli: to increase surface area for absorption and secretion
-Keratinized: Dead cells filled with protein Keratin to help against abrasion (skin).
*Basal Surface: They have a basement membrane.
-Basement membrane is made of collagen and glycoprotein, helps attach the epithelium
to the connective tissue underneath, gives room for the cell to go through mitosis,
determines what gets into epithelium from connective tissue below.
*Avascular: No blood vessels! They get blood from connective tissue below through basement membrane.
*Regeneration: Very Fast!
*Nerve Endings: Usually A lot!
HOW WE NAME CLASSES OF EPITHELIA!
Based on Shape:
*Squamous Cell Epithelia: Thin and Flat
*Cuboidal Epithelia: Square Shaped
*Columnar Epithelia: Tall, Slender Rectangles
Based on Layers:
*Simple Epithelium: Single Layer of Cells
*Stratified Epithelium: Several Layer of Cells
NAMED ACCORDING TO THE CELLS AT THE FREE SURFACE!!!
Simple Squamous Epithelium: Absorption, diffusion, reduce friction (Lung, Kidney Tubules)
Mesothelium: Lines Body Cavities
Endothelium: Lines heart and blood and lymphatic vessels.
*Simple Cuboidal: Glands, Ducts, Kidney Tubules
*Simple Columnar: Absorption & Secretion (Lining of stomach, intestine, Uterine Tubes)
*Stratified Squamous: Protects against attacks and abrasions (Skin, Inside the Mouth)
*Stratified Cuboidal: Sweat Ducts and Mammary Glands
*Stratified Columnar: Protection (Mammary Gland, Urethra)
*Transitional Epithelium: Tolerates repeated cycles of stretching a recoiling and returns
To its previous shape without damage, Appearance changes as stretching occurs.
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*Pseudostratified Columnar: Looks like Stratified (Pseudo=False), Each cell attaches to
basement membrane, not all cells make it to the free surface (Respiratory Tract).
Glandular Epithelia:
Endocrine Glands:
Release Hormones:
*Into Interstitial Fluid
*No Ducts…Directly into Blood!
Exocrine Glands (Merocrine):
Produce Secretions:
*Onto Epithelial Surfaces
*Through Ducts
Merocrine Secretion:
*Produced by Golgi Apparatus
*Released by Vesicles (Exocytosis)
*Sweat Glands, Salivary Glands, Pancreas
Apocrine Secretion:
*Produced in Golgi Apparatus
*Released by Shedding Cytoplasm
*Mammary Gland
Holocrine Secretion:
*Is released by cells bursting, Killing gland cells
*Gland cells replaced by stem cells
*Sebaceous Gland
Glandular Epithelia:
Types of Secretions:
Serous Glands: Watery Secretions
Mucus Glands: Secrete Mucins
Mixed Exocrine Glands: Both Serous and Mucous
CONNECTIVE TISSUE:
-Connects Epithelium to the rest of the body (Basal Lamina)
*Provides Structure (Bone)
*Stores Energy (Fat)
*Transports Materials (Blood)
*Has no contact with environment
Matrix (Fibers):
Collagen: Strong and Flexible
Elastic: Stretch
Reticular: Network of fine collagen fibers
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Ground Substance: Determines the characteristics of connective tissue. There are few cells in the ground substance.
*Blood: Ground substance like water
*Areolar: (Always below epithelium tissue). Ground substance has Hyaluronic Acid that
makes it viscous.
*Cartilage: Ground substance of chondroitin and glucosamine.
*Bone: Ground substance has calcium salt that makes it hard.
*Connective Tissues are Vascular (except in cartilage) and have Nerve Endings!
Classification of Connective Tissue:
Connective Tissue Proper (Loose, Dense, Regular, Irregular)
*Connect and Protect
Fluid Connective Tissues
*Transport
Supportive Connective Tissues
*Structural Strength
Scattered Cells in Connective Tissues:
Fibroblasts: Connective Tissue Proper
*Synthesizes the extra cellular matrix and collagen.
Chondroblasts: Cartilage
Osteoblasts: Bone
Hemopoietic Stem Cells: Blood (WBC’s, plasma cells, macrophages, mast cells).
Connective Tissue Proper Cells
FIBROBLASTS: Mainly produce collagen.
*The most abundant type cell
-Found in all connective tissue proper
-secrete proteins and hyaluronan
FIBROCYTES: Circulate in peripheral blood and produce connective tissue proteins.
*The second most abundant cell type
-Found in all Connective Tissue Proper
-Maintain the fibers of connective tissue proper
MACROPHAGES:
*Large cells of the immune system
-Eat pathogens and damaged cells
ADIPOCYTES:
*Fat Cells
Mesenchymal Cells:
*Stem cells that respond to injury or infection.
-Differentiate into fibroblasts and macrophages.
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MELANOCYTES:
*Synthesize and stores the brown pigment Melanin!
MAST CELLS:
*Stimulates inflammation after injury or infection.
-Releases histamine or heparin
*Histamine: Blood to Tissue
*Heparin: Keeps blood from clotting too fast!
LYMPHOCYTES:
*Specialized immune cells in lymphoid (lymphatic) system.
-Lymphocytes my develop into plasma cells (plasmocytes) that produce
antibodies.
MICROPHAGES:
*Phagocytic Blood Cells
-Neutrophils and Eosinophils
Connective Tissue Fibers:
Collagen Fibers
*Most common fibers in connective tissue proper
*Strong and Flexible
*Resist Force in one direction
-Tendons and Ligaments
Reticular Fibers
*Network of Interwoven Fine Collagen Fibers
*Strong and Flexible
*Resist Force in Many Directions
*Sheaths around organs
Elastic Fibers
*Contains Elastin
*Return to original Length after stretching
-Elastic ligaments of Vertebrae
Embryonic Connective Tissues:
*Are not found in adults
*MESENCHYME (Embryonic Stem Cells)
-The first connective tissue in embryos
*MUCOUS CONNECTIVE TISSUE
-Loose Embryonic Connective Tissue
LOOSE CONNECTIVE TISSUE
*The packing materials of the body
*Three Types in Adults: 1) Areolar 2) Connective 3) Reticular
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AREOLAR:
*Viscous Ground Substance (Hyaluronic Acid)
*Collagen and Elastic Fibers
*Scattered Cells of Fibroblast and Mast Cells
*Found under epithelial Tissue
ADIPOSE:
*Ground Substance (Hyaluronic Acid)
*Prevents Heat Loss
*Found around organs and under skin
-White fat (adults)
-Brown fat (newborn)
RETICULAR:
*Provides Support
*Supportive Fibers (stroma)
-supportive functional cells (parenchyma)
*Reticular Organs (Spleen, Liver, Lymph Nodes, bone marrow)
DENSE CONNECTIVE TISSUE:
*Connective tissue proper, tightly packed with high numbers of collagen or elastic fibers.
-Dense Regular Connective Tissue
-Dense Irregular Connective Tissue
-Elastic Tissue
Dense Regular Connective Tissue:
*Tightly packed, parallel collagen fibers, with fibroblast cells.
-Tendons: Attach muscles to bones
-Ligaments: Attach bone to bone
-Aponeuroses: Attach in sheets to large, flat muscles.
Withstands great tensile stress when pulling force is applied in one direction
DENSE IRREGULAR CONNECTIVE TISSUE
*Interwoven network of collagen fibers with fibroblast cells
-Layered in skin, around cartilages and around bones
-Form capsules around some organs (e.g. Liver, Kidney)
-Provide strength to resist forces applied from many directions.
ELASTIC TISSUE:
*Elastic Ligaments of Spinal Vertebrae
*Cushion Shocks
SUPPORTIVE CONNECTIVE TISSUE:
CARTILAGE:
-Gel-type ground substance
-For shock absorption and protection
-No blood vessels or nerve endings
Bone:
-Calcified (Made rigid by calcium salts, minerals); For Weight Support!
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Cartilage:
Cartilage Matrix: Chondroitin Sulfates
Scattered Cells: Chondrocytes in Lacunae
Hyaline Cartilage (Most Common):
*Stiff, flexible support
*Reduces friction between bones
*Found in synovial joints, rib tips, sternum and trachea
Elastic Cartilage: Supportive, but bends easily; Found in external ear and epiglottis.
FIBROUS CARTILAGE:
-Limits Movements
-Prevents bone to bone contact
-Pads Knee Joint
-Found between Pubic bone and Intervertebral Discs
Supportive Connective Tissues:
*Bone or Osseous Tissue
*Strong (Calcified: Calcium Salt Deposits)
*Resists Shattering (Flexible Collagen Fibers)
Osteocytes (Bone Cells)
*Arranged around Central Canals within Matrix
*Small Channels through matrix (Canaliculi) access blood supply
Periosteum: Covers bone surfaces.
FLUID CONNECTIVE TISSUES: BLOOD
-Plasma a watery matrix with dissolved proteins
-Formed elements of blood: RBC (Erythrocytes), WBC (Leukocytes), Platelets
FLUID CONNECTIVE TISSUES: LYMPH
-In Lymph Vessels, Immunity, Watery Matrix, No Fibers
MUSCLE TISSUE: Specialized for Contraction
-Skeletal Muscle
-Cardiac Muscle
-Smooth Muscle
SKELETAL MUSCLE TISSUE:
-Are long and cylindrical
-Are multinucleated
-Striated and Voluntary
CARDIAC MUSCLE TISSUE:
-Striated and Involuntary
-Single Nucleus
-Form branching networks connected at intercalated discs.
SMOOTH MUSCLE TISSUE:
-Small and Tapered
-Non-Striated and Voluntary
-Single Nucleus
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Neural Tissue (Nervous Tissue)
-Specialized for conducting electrical impulses
-Processes information and controls responses
-Neural tissue is concentrated in the CNS (Brain, Spinal Cord)
Neural Tissue:
*Neurons: Performs electrical communications
*Neuroglia: Supporting cells, Repair (Mitosis), Supply nutrients to neurons
Cell Parts of A Neuron:
-Cell Body (Soma): Contains the Nucleus and the Nucleolus.
-Dendrites: Short branching extending from the cell body (Receiving Incoming Signals)
-Axon (Nerve Fiber): Long, thin extension of the cell body; carries outgoing electrical signals
to their destination.
MEMBRANES:
-Are physical barriers that line or cover portions of the body
-Consist of:
*An epithelial Tissue
*Supported by Connected Tissue Areolar
FOUR TYPES OF MEMBRANES:
*Mucous Membranes
*Serous Membranes
*Cutaneous Membranes
*Synovial Membranes
Mucous Membranes (Mucosa):
*Line passageways that have external connections with a different epithelial tissue
-Always have Goblet Cells
*Epithelial surfaces must be moist: To reduce friction and facilitate absorption and excretion.
*Lamina Propria: Is areolar tissue.
*Mucous: Lines passageways that open to the exterior (Digestive and Respiratory Tracts)
Serous Membranes:
*Secret Watery Fluid
*Always has Simple Squamous Epithelial and Areolar
*Line Cavities not open to the outside
*Reduce Friction
*Have a parietal portion covering the cavity
*Have a visceral portion (serosa) covering the organs
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The Serous Membranes:
PLEURA:
-Lines pleural cavities
-Covers lungs
Peritoneum:
-Lines Peritoneal Cavity
-Covers Abdominal Organs
Pericardium:
-Lines Pericardial Cavity
-Covers Heart
Serous: Moist membranes found in closed ventral body cavity
SYNOVIAL MEMBRANE:
*Mostly Areolar Tissue with few cells on top
*Line moving, articulating joint cavities
*Produce synovial fluid (lubricant)/Hyaluronic Acid
*Protect the end of bones
Cutaneous Membrane:
Cutaneous-Skin
*It is an organ system consisting of Keratinized Stratified Squamous Epithelium
*It is a dry membrane
Chapter 5: Integumentary System
-The INTEGUMENT is the largest system of the body!
*16% of Body Weight
- The Integument is made up of two parts:
*Cutaneous Membrane (skin)
-Keratinized stratified squamous epithelium
-Areolar Underneath
*Accessory Structures
*PROTECTS underlying tissues and organs.
*EXCRETES salts, water and organic wastes (glands)
*MAINTAINS body temperature (insulation and evaporation)
*SYNTHESIZES vitamin D3 for absorption of calcium
*BLOOD FLOW REGULATION:
-COLD: Blood vessels constrict
-HOT: Blood vessels dilate
*DETECTS touch, pressure, pain and temperature
The cutaneous membrane has two components:
-Outer Epidermis
*Superficial Epithelium (epithelial tissues)
-Inner Dermis
*Connective Tissues
INTRO TO THE INTEGUMENTARY SYSTEM
Subcutaneous Layer: (Superficial fascia or hypodermis)
*Loose Connective Tissue
*Below the dermis
*Location of Hypodermic Injections
Epidermis
-Avascular: Keratinized stratified squamous epithelium (nutrients and oxygen diffuse
from capillaries in the dermis.)
Cells of the Epidermis:
-Keratinocytes: Contain large amounts of keratin.
*The most abundant cells in the epidermis
Structure of the Epidermis:
-The five strata of Keratinocytes in thick skin
-From Basal Lamina to Free Surface
1. Stratum Basale (Germinativum)
2. Stratum Spinosum
3. Stratum Granulosum
4. Stratum Lucidum
5. Stratum Corneum
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Epidermis (Stratum Basale): The “Germinative” Layer
*Has many germinative (stem) cells or basal cells.
*Forms a strong bond between epidermis and dermis
*Forms epidural ridges (i.e. fingerprints)
*Dermal Papillae (tiny mounds)
-Increase the area of the Basal Lamina
-Strengthen attachment between epidermis and dermis
Keratinization: The formation of a layer of dead, protective cells filled with keratin
-Occurs on all exposed skin surfaces except eyes
-It takes 15-30 days for a cell to move from Stratum Basale to stratum corneum.
Cells of the Epidermis:
Keratinocytes: Majority of Epidermal cells
Langerhans Cells: Macrophages
Melanocytes: Stratum Basale…Pigment producing!
Merkel Cells: Receptors for sense of touch
Vitamin D3: Produced in epidural cells.
-In the presence of UV Radiation
-To aid absorption in of calcium and phosphorus
-Insufficient Vitamin D3 can cause Rickets
The Dermis: 2 Layers!
1. The Papillary Layer
a. Consists of areolar tissue
b. Has dermal papillae projecting between epidural ridges.
2. The Reticular Layer
a. Consists of Dense Irregular Connective Tissue
b. Contains collagen and elastic fibers
Dermal Strength and Elasticity: Presence of two types of fibers…
*Collagen Fibers: Very strong, resist stretching but bend easily (provide flexibility)
*Elastic Fibers: Permit stretching and then recoil to original length
-Limits the flexibility of collagen fibers to prevent damage to tissue.
*Skin Turgor: Properties of flexibility and resistance.
INNERVATION OF THE SKIN:
Nerve fibers in skin control… 1) Blood Flow 2)Gland Secretions 3)Sensory Receptors
Tactile Disc: Monitor Merkel Cells
The Hypodermis:
*Is made of elastic areolar and adipose tissues
*Is connected to the reticular layer of integument by connective tissue fibers
*Has few capillaries and no vital organs
*Site of subcutaneous injections using hypodermic needles.
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Capillaries and Skin Color:
Hemoglobin: Pink Skin Color
*Oxygenated red blood contributes to skin color
*Blood vessels dilate from heat, skin reddens
*Blood flow decreases, skin pales
Melanin:
-Made by melanocytes
-Brown to black color of skin
-Protection against UV light
Carotene:
-Found in Stratum Corneum
-Yellowish tint to skin
Illness and Skin Color:
*Jaundice
-Buildup of bile produced by liver
-Yellow Color
*Addison Disease
-A disease of the pituitary gland
-skin darkening
-Bronze Color
Albinism: A defect of melanin production.
Vitiligo: Occurs when melanocytes die or unable to function normally. Autoimmune!
Nevi: These are commonly named ‘birthmarks’ and ‘moles.’
Freckles: Clusters of concentrated melanin.
Functions of Hair:
-Protects and insulates
-Guards openings against particles and insects
-Is sensitive to very light touch
Regions of the Hair:
-Hair Root: Lower part of the hair attached to the integument
-Hair Shaft: Upper part of the hair with no attachment to the integument
Hair Follicle:
-Located deep in dermis
-Base is surrounded by sensory nerves(root hair plexus)
Arrector Pili Muscle:
-Involuntary Smooth Muscle
-Causes hairs to stand up
-Produces Goose Bumps
Sebaceous Glands:
-Lubricate the hair
-Inhibits bacteria growth
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Hair Production: Begins at the base of a hair follicle, deep in the dermis.
-The hair papilla contains capillaries and nerves
-The hair bulb produces hair matrix
-Produces hair structure
-Pushes hair up and out of skin
-As hair is produced, it is keratinized
-Hair color is produced by melanocytes at the hair papilla
Sebaceous (Oil) Glands: Holocrine Glands
-Secrete sebum
-Discharge directly onto the skin surface
-Sebum: Lubricates and protects the epidermis, inhibits bacteria
*Apocrine Sweat Glands:
Found in armpits, around nipples and groin
Secrete particles into hair follicles
Produce sticky, cloudy secretions and break down causes odors
*Merocrine (Eccrine) Sweat Glands:
-Widely distributed on body surface
-Especially on palms and souls
-Discharge directly onto skin surface
-Cools skin, excretes water and electrolytes, flushes microorganisms and harmful
chemicals from the skin.
*Ceruminous Glands: Modified sweat gland; located in E.A.C.
-Produce cerumen (earwax)
-Protect the eardrum
*Nails protect fingers and toes: Made with dead cells packed with Keratin
*Nail Production: Occurs in a deep epidermal fold near the nail root!
ABCDE’s of Skin Cancer
-Asymmetry
-Border
-Color
-Diameter
-Evolving/Changing
Three major types of Skin Cancer are:
1. Basal Cell Carcinoma
2. Squamous Cell Carcinoma
3. Melanoma
Basal Cell Carcinoma:
-Least Malignant and Most Common skin cancer.
-Stratum Basale cells proliferate and invade the dermis and hypodermis.
***SLOW GROWING AND DOES NOT OFTEN METASTISIZE***
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Squamous Cell Carcinoma: Arises from Keratinocytes from stratum spinosum.
Grows rapidly and metastasizes of not removed.
Prognosis is good.
*Cancer of melanocytes is the most dangerous type of skin cancer because it is:
-Lease malignant and most common
-Highly metastatic
-Resistant to chemo!
First Degree Burn:
-Epidermis damaged (Superficial)
-Localized redness, swelling, pain
Second Degree Burn:
-Epidermis destroyed (part of dermis)
-localized redness
-Swelling
-pan
-blister
Third Degree Burn
Epidermis and entire dermis is destroyed
Gray, white black, cherry red or black!
NO PAIN!!!
Rule of 9
Tissue Repair:
-Inflammation and Migratory Phase: Bleeding and dilation of the blood vessels to
increase blood flow. Mast cells release histamine. Brings in plasma with antibodies and
clotting factors. (signs of inflammation: swelling, redness, heat, pain)
-Granulation (proliferation) phase: Building of new blood vessels and layers of
connective tissue. (Fibroblasts lay down new layers of collagen).
-Maturation Phase (Regeneration/Scarring): Restores normal function to tissue
Surface of a cut is regenerated.
Fibrosis: Damaged tissue replaced with scar tissue, mainly collagen. Normal function not
restored.
Parenchyma: Leads to functional, regenerated cells
Stroma: Fibroblast cells make the tissue causing fibrosis.
Fibroblasts produce scar tissue
-A raised Keloid may form
-Keloid Scar: Excessive production of Collagen, growth exceed boundaries of wound,
tumor like appearance.
Hypertrophic Scar: Overproduction of collagen, growth does not exceed the boundaries of the wound, raised bump occurs.
Chapter 6: Bones
*Functions of the Skeletal System:
-Support (attachment of soft tissue)
-Storage of Minerals (calcium)
-Storage of Lipids (Yellow Marrow)
-Blood Cell Production (Red Marrow)
-Protection (Brain & Spinal Cord)
-Leverage (Motion)
Anatomy of Long Bone:
*Diaphysis: Shaft of Long Bone
*Epiphysis: Ends of Long Bone
*Periosteum: Covers Outer Surface of Bone
-Osteogenic Layer: Cells for Bone Formation or Bone Break Down
-Fibrous Layer: Dense Irregular Connective Tissue, Attachment of muscle tendons
to bones.
*Endosteum: Inner Marrow Lining
*Epiphyseal Plate: Hyaline Cartilage until adulthood
*Articular Cartilage: Cartilage that remains on the outer surface of the Epiphysis where
the bone forms a joint with another bone.
Structure of a Flat Bone:
*Resembles a sandwich of Spongy Bone
*DIPLOE: Layer of spongy bone between the compact bone.
Bone Tissue:
*Characteristics of Bone Tissue:
*Dense Matrix Containing
-Deposits of Calcium Salts
-Osteocytes (Bone Cells) within Lacunae organized around blood vessels
*Canaliculi
-Form Pathways for Blood Vessels
-Exchange Nutrients and Wastes
*Periosteum
-Covers outer surfaces of bone
-Consists of outer fibrous and inner cellular layers
Bone Matrix:
*Ground Substance
-Calcium Phosphate and Calcium Carbonate
-Compression Strength
*If you took this away, the bones would become very RUBBERY!!!
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*Fibers
-Collagen, Elastic
-Organic
-Flexible Strength
*If you took this away, the bones would become very BRITTLE!!!
Bone Tissue
*The Cells of Bone
-Osteocytes
-Osteoblasts
-Osteoprogenitor Cells (Osteogenic Cells)
-Osteoclasts
Scattered Cells:
*Osteoprogenitor Cells “Preosteoblasts”
-Found in Endosteum and Periosteum
>Mesenchymal Stem Cells>Osteoprogenitor Cells>Osteoblasts
*Osteoblasts “Build Bone”
-Make New Bone
-Osteoid: Matrix produced by osteoblasts, but not yet calcified to form bone.
*Osteocytes
-Mature Bone Cells…Most bone cells are of this type!
-Osteoblasts>Trapped in a space(Lacuna)>Osteocytes
*Osteoclasts
-Break down bone
-Derived from white blood cells (Monocyte)
Compact and Spongy Bone:
*The Structure of Compact Bone
-Osteocytes are arranged in concentric lamellae
-Around a Central Canal (Haversian Canal) containing blood vessels
-Perforating Canals (Canals of Volkmann) :
-Perpendicular to the Central Canal
-Carry blood vessels into bone and marrow
*Circumferential Lamellae
-Lamellae wrapped around the long bone
-Bind Osteons together
*Osteon: The Basic Unit of Compact Bone
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Spongy Bone:
*The Structure of Spongy Bone
-Does not have osteons
-The matrix forms an open network of Trabeculae
-Trabeculae have NO blood vessels
-Trabeculae is filled with Red Bone Marrow (which has blood vessels)
Comact Bone:
-The hard-outer surface of bone.
-Composed of OSTEONS
-Concentric layers of osteocytes (lamellae)
-Lamellae surround a central canal (Haversian Canal)
-Haversian Canal
-Carry blood vessels
-Run parallel to bone surface
Spongy Bone:
-Found at epiphysis of long bones and interior of flat bones such as the sternum.
-No osteons
-Trabeculae
-Red Marrow
-Osteocytes get nourishment from canaliculi
Bone Development:
*Human bones grow until about age 25
*Osteogenesis: Bone formation
*Ossification: The process of replacing other tissues with bone
Bone Formation and Growth
Bone Development
*Calcification
-The process of developing calcium salts
-Occurs during bone ossification and in other tissues
*Ossification
-Intramembranous Ossification
-Starts with mesenchymal or fibrous connective tissue
-Makes flat bones (Mandible, Clavicle, Skull bones)
-Endochondral Ossification
-Ossifies bone that originate as hyaline cartilage
-Most bone originates as Hyaline Cartilage
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Epiphyseal Plate: Mae of Hyaline Cartilage and shows on Xray as a black line
Epiphyseal Line: When long bone stop growing, after puberty. Epiphyseal Cartilage disappears.
Appositional Growth in Length: Bone is deposited on the DIAPHYSEAL side of epiphyseal plate
Appositional Growth in Width: Compact bone thickens and strengthens with layers of
circumferential lamellae by osteoblasts of periosteum.
Bone Remodeling
*Bone continually remodels, recycles, and replaces.
*The Adult Skeleton
-Recycles and renews bone matrix
-Involves osteocytes, osteoblasts, osteoclasts
*Turnover Rate Varies
-If deposition is greater than removal, bones get stronger
-If removal is faster than replacement, bones get weaker
Exercise:
*Mineral recycling allows bones to adapt to stress
*Heavily stressed bones become thicker and stronger
*Bone degenerates quickly
*Up to one third of bone mass can be lost in a few weeks of inactivity
*Bones store calcium and other minerals
*Calcium is the most abundant mineral in the body
*Calcium ion are vital to:
-membranes
-neurons
-muscle cells, especially heart cells
*In Calcium Regulation, Homeostasis is Maintained by Calcitonin and Parathyroid Hormone,
which control storage, absorption and secretion.
Parathyroid Hormone (PTH):
*Produced by Parathyroid Glands
*Increases calcium ion levels in blood by STIMULATINGosteoclastic activity
Calcitonin:
*Secreted by C(Parafollicular) Cells in thyroid
*Decreases Calcium ion levels in blood by INHIBITING osteoclastic activity
Simple/Closed Fractures: Bone is broken but there is no break in the skin!
Open or Compound Fracture: Broken bone breaks the skin!
Colle Fracture: A break in the distal portion of the radius…is the result of trying to break a fall.
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Greenstick Fracture: Bone breaks incompletely, only one side of the shaft breaks, the other side bends.
STAGES IN THE HEALING OF A BONE FRACTURE:
1. Hematoma Formation
a. Torn blood vessels hemorrhage
b. A mass of clotted blood (hematoma) forms at the fracture site
c. Site becomes swollen, painful and inflamed
2. Cartilage Callus Forms (Soft Callus)
a. Fibrocartilage (soft callus)
b. Osteoblasts and fibroblasts migrate to the fracture
c. Fibroblasts secrete collagen fibers that connect broken bone ends.
d. Osteoblasts begin forming spongy bone
3. Spongy Bone Callus Formation
a. New Bone Trabeculae appear in the soft callus
b. Soft Callus converts into a bony hard callus
4. Remodeling: Compact Bone Formation
a. Excess material on the bone shaft exterior and in the medullary canal is removed
b. Compact Bone is laid down to reconstruct shaft walls
Osteopenia: Bones become thinner and weaker with age
-Begins between ages 30 and 40
Osteoporosis: Severe Bone Loss
-Over age 45
-29% Women
-18% Men
Chapter 7: Axial Skeleton
*Bones are Classified by: Shape, Internal Tissue Organization, Bone Markings
Classified by Shape:
*Long Bones: Longer than they are wide, they have a shaft and two ends (Humerus).
*Short Bones: Cube-Shaped bones of the wrist and ankle.
-Sesamoid Bones: Bones that form within tendons (Patella)
*Flat Bones: Thin, flattened and a bit curved (sternum and most skull bones).
*Irregular Bones: Bones with complicated shapes (Vertebrae and hip bones).
*Sutural Bones: Wormian bones found in skull.
SKELETON: Two (2) Main Parts:
*Axial Skeleton: Makes the Axis of the body.
-Skull (Cranial and facial) thoracic cage, vertebral column
*Appendicular Skeleton: Makes the appendages.
-Arms, legs, hips, clavicle, scapula
The Axial Skeleton:
*Forms the longitudinal axis of the body (has 80 bones)
*The Skull: 22 Bones
-8 Cranial
-14 Facial
*Vertebral Column: 24 Vertebrae, Sacrum, Coccyx
*Thoracic Cage: 24 Ribs (12 pair), The Sternum
*Functions of The Axial Skeleton:
-Supports and Protects Organs in Body Cavities
-Attaches to Muscles of: Head, Neck, Trunk; Respiration; Appendicular Skeleton
Cranial Bones: 8
-Occipital, Fontal, Sphenoid, Ethmoid, Parietal (2), Temporal (2)
Facial Bones: 14
-Maxilla (2), Lacrimal (2), Nasal (2), Zygomatic (2), Mandible
-DEEP FACIAL BONES: Palatine Bones (2), Inferior Nasal Conchae(2), Vomer
FACE:
*Hard Palate: Maxillary + Palatine
*TMJ: Only Moveable Joint of the Face
*Teeth: Mandible + Maxillary Bones
EYE SOCKET:
-Ethmoid, Sphenoid, Zygomatic, Lacrimal, Frontal, Maxilla, Palatine
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Sinus:
*Air Cavity
*Drain to the nasal cavity
*Acts as a chamber that adds resonance to voice
Types and where they are found:
-Frontal Sinus: Frontal Bone
-Sphenoid Sinus: Sphenoid Bone
-Ethmoid Sinus: Ethmoid Bone
-Maxillary Sinus: Maxilla
*Frontal Sinus: If infected…pain in forehead
*Ethmoid Sinus: If infected…pain between the eyes
*Maxillary Sinus: If infected…pain in upper jaw
*Sphenoid Sinus: If infected…pain in back of the eye
Conchae:
Function…
-Form 3 Groove-Like Air Passages
-Inhaled Air Flows in a Steady Pattern
Ethmoid Bone:
-Superior Nasal Conchae
-Middle Nasal Conchae
-Inferior Nasal Conchae
Hyoid Bone: Does not articulate with any other bone
-It is held in place with ligaments
-Provides attachments to the muscles of the floor of the mouth, tongue, larynx
-The Epiglottis and Pharynx are posterior
Vertebral Column:
*Atlas (C1), Axis (C2)
*Intervertebral Discs
*Curves of the Spine
*7 Cervical
-Special bones of Cervical: C1(Atlas), C2(Axis)
*12 Thoracic
*5 Lumbar
*Sacrum
*Coccyx
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*Primary Curve: Thoracic Curvature, Pelvic Curvature
-Remnant left from Original C-curve
*Secondary Curve: Cervical Curvature, Lumbar Curvature
-Baby Begins to Hold Up Head (Cervical)
-Baby Begins to Sit and Walk (Lumbar)
C1/Atlas:
*Articulates with Occipital Condyles
*Lacks a body and spinous process
*Has anterior and posterior arches
*Articulation with the Occipital Condyles allow you to nod “YES”
C2/Axis:
*Has the Dens/Odontoid Process
*Articulation with the Atlas allows you to nod “NO” (Rotation)
Cervical Vertebrae:
Unique Characteristics:
-Bifurcated Spinous Process
-Transverse Foramen
Thoracic Vertebrae:
Unique Characteristics:
-Spinous Process points downward
-Has articulating facets for the ribs
Lumbar Vertebrae:
Unique Characteristics:
-Very blunt, flat spinous processes
-Large Vertebral Body
Intervertebral Discs:
*Outer Annulus Fibrosus
-Several Layers of Fibrocartilage
*Inner Nucleus Pulposus
-Contains loose fibers in a gel
-Acts as a shock absorber
*Herniated Disc
-Nucleus Pulposus: Breaks through Anulus Fibrosis
-Spinal Nerve become distorted
*Spine Deformities:
-Kyphosis (Hunch Back), Lordosis (Swayback), Scoliosis
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The Thoracic Cage:
*Supports the Thoracic Cavity
-Consists of : Thoracic Vertebrae, Ribs, Sternum
*The Rib Cage: Formed of Ribs and Sternum
FUNCTIONS OF THE THORACIC CAGE:
*Protects organs of the Thoracic Cavity
-Heart, Lungs, Thymus
-Attaches Muscles
RIBS:
*12 Pairs of Long, Flat Bones
*All Ribs are attached POSTERIORLY to Spinal Column
*Ribs are Divided into Two Types:
-True Ribs
-False Ribs
Ribs 1-7 (TRUE RIBS):
-Connected to the sternum directly by Costal Cartilages
RIBS 8-12 (FALSE RIBS):
-DO NOT ATTACH DIRECTLY TO THE STERNUM
-Vertebrochondral Ribs (Ribs 8-10)
-Fuse Together
-Merge with Cartilage before reaching the sternum
FLOATING or VERTEBRAL RIBS (Ribs 11-12):
-Connect only to the vertebrae and back muscles
-Have NO CONNECTION with the Sternum
The Sternum:
*A flat bone
*In the midline of the Thoracic Wall
*Three Parts of the Sternum: 1. Manubrium 2. Sternal Body 3. Xiphoid Process
ARTICULATIONS:
*Superior Aspect of Atlas Articulate with Occipital Condyle
*C1 and Occipital Condyle allows you to “Say Yes”
*Inferior aspect of Atlas Articulates with Superior Aspect of Axis
*C1 and C2 allows you to “Say No”
*Inferior L5 Articulates with Superior Sacrum
*Inferior Sacrum Articulates with Superior Coccyx
*Lateral Sacrum Articulates with Medial Ilium
Chapter 8: Appendicular Skeleton
*The limbs and supportive girdles make up the Appendicular Skeleton.
PECTORAL GIRDLE
*Also known as the shoulder girdle
*Connects the arms to the body
*Consists of Two (2)Clavicles and Two (2) Scapulae
*Connects with the Axial Skeleton only at the Manubrium!
SCAPULAE
*Also called Shoulder Blades
*Articulates with arm and clavicle
*The scapular head holds the Glenoid Cavity which articulates with the Humerus to form the
shoulder joint.
-Processes of the Glenoid Cavity:
-Coracoid Process
-Acromion: Articulates with the clavicle at the acromioclavicular joint.
Upper Limbs:
*The upper limbs consist of arms, forearms, wrists and hands.
The Arm (Brachium):
-Articulations: The PROXIMAL end articulates with the shoulder girdle. The DISTAL end
articulates with Ulna and Radius.
The Forearm (Antebrachium):
-Consists of two long bones:
*Ulna (Medial): The Olecranon (Proximal End)
-Articulates with trochlea of humerus.
*Radius (Lateral): Articulates with wrist and ulna (Distal End)
The Four Proximal Carpal Bones: SCAPHOID, LUNATE, TRIQUETRUM, PISIFORM
The Four Distal Carpal Bones: TRAPEZIUM, TRAPEZOID, CAPITATE, HAMATE
METACARPALS: The Five Long Bones of the Hand (Palm)
*Numbered I-V from lateral (thumb) to medial.
*Articulations:
-Proximal End Articulates with Distal Row of Carpals
-Distal End Articulate with Proximal End of Proximal Phalanges
*Phalanges:
-14 Total Finger Bones
-Pollex (Thumb): Two Phalanges (Proximal, Distal)
-Fingers: Three Phalanges (Proximal, Middle, Distal)
*Articulations of Phalanges:
-Proximal Phalanges:
-Proximal end to distal end of metacarpals
-Distal end to proximal end of middle phalanges
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-Middle Phalanges:
-Proximal end to distal end of proximal phalanges.
-Distal end to proximal end of distal phalanges.
-Distal Phalanges:
-Proximal end to distal end of middle phalanges.
*PELVIC GIRDLE:
-Made up of two hip bones (Coxal Bones)
-Coxal Bones:
*Made up of three fused bones: 1. Ilium 2. Ischium 3. Pubis
COMPARISON OF MALE And FEMALE
*Female lighter, shallower pubic arch (>100 degrees), and pubic inlet round or oval.
*Male heavier, upper pelvis nearly vertical, coccyx more vertical and pelvic inlet heart shaped.
Lower Limbs:
*Functions: Weight bearing, motion.
*Bones of the Lower Limbs: Femur (Thigh), Patella (kneecap), Tibia & Fibula (Leg),
Tarsals (Ankle), Metatarsals (Foot), Phalanges (Toes).
*Femur & Patella: Proximal end, head of the femur articulates with the pelvis at acetabulum.
*Distal end of the femur articulates with proximal end of Tibia and Patella
*The Patella (Kneecap): A sesamoid bone formed within tendon of quadriceps femoris.
*Tibia: Distal end of Femur articulates with proximal end of Tibia.
-Medial and Lateral Condyles articulates with Femur
-Distal Expansion: Medial Malleolus articulates with Talus of foot.
*Fibula: Does not bear any body weight; Head=Proximal end.
-Lateral Malleolus=Distal Expansion (Joined to tibia by interosseous membrane)
THE ANKLE (Tarsus):
Bones of the Ankle:
*Talus: Most superior Tarsal Bone
-Forms ankle joint with tibia and fibula
-Sits upon calcaneus and articulates w/navicular
*Calcaneus (Heel Bone): Attaches to calcaneal (Achilles) tendon.
*Cuboid: Articulates with Calcaneus
*Navicular: Articulates with Talus and three cuneiform bones.
-Distal Row of Tarsal Bones: Medial Cuneiform, Intermediate Cuneiform, Lateral
Cuneiform.
Metatarsal Bones of the Foot
*Five Long Bones of Foot
*Numbered I-V (medial to lateral)
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Articulation: Distal ends articulate with proximal ends of proximal phalanges.
*Phalanges of the Foot: 14 bones of the toes.
-Hallux: Big Toe (Great Toe), Two Phalanges (distal, proximal)
-Other four Toes: Three (3) Phalanges (distal, medial, proximal)
ARTICULATIONS:
*Clavicle
-Lateral Side: Acromion of Scapula (Shoulder Joint)
-Medial Side: Sternum
*Scapula
-Acromion of Scapula and Clavicle
-Body of Scapula does not articulate with the ribs
*Shoulder (Glenoid Cavity)
-Acromion of Scapula and lateral part of clavicle with proximal humerus (head of
humerus).
*Elbow
-Distal end of humerus with proximal ends of Ulna and Radius
*Wrist
-Proximal carpals of wrist with distal end of ulna and radius.
HIP BONES: Ilium, Ischium, Pubis
*Hip and Vertebral Column Articulations
-Inferior of L5 articulates with Superior Sacrum
-Medial aspect of Ilium articulates with lateral Sacrum
-Inferior aspect of sacrum articulates with superior coccyx
CLAVICLE:
*Sternal End (medial end) articulates with sternum
*Acromial End (lateral end) articulates with scapula
*Sternal End Rounded-Acromial End Flattened
Humerus:
*Distal End Articulates with Proximal Ulna
*Proximal End Articulates with Glenoid Fossa