Introduction and TissuesHuman Anatomy
BIOL 1010
Liston Campus
What is Anatomy?Anatomy (= morphology): study of body’s structurePhysiology: study of body’s function
Structure reflects Function!!! Structure reflects Function!!! Branches of Anatomy Gross: Large structures Surface: Landmarks Histology: Cells and Tissues Developmental: Structures change through life Embryology: Structures form and develop before birth
Hierarchy of Structural Organization
Each of these build upon one another to make up the next level:Chemical level CellularTissueOrganOrgan systemOrganism
Hierarchy of Structural Organization
Chemical level Atoms combine to make molecules 4 macromolecules in the body
Carbohydrates Lipids Proteins Nucleic acids
Hierarchy of Structural Organization
Cellular Made up of cells and cellular
organelles (molecules) Cells can be eukaryotic or prokaryotic Organelles are structures within cells that
perform dedicated functions (“small organs”)
http://cmweb.pvschools.net/~bbecke/newell/Cells.html
Hierarchy of Structural Organization
Tissue Collection of cells that work together
to perform a specialized function 4 basic types of tissue in the human
body: Epithelium Connective tissue Muscle tissue Nervous tissue
www.emc.maricopa.edu
Hierarchy of Structural Organization
Organ Made up of tissue
Heart Brain Liver Pancreas, etc……
Pg 181
Hierarchy of Structural OrganizationOrgan system (11) Made up of a group of related organs
that work together Integumentary Skeletal Muscular Nervous Endocrine Cardiovascular Lymphatic Respiratory Digestive Urinary Reproductive
Circulatory
Pg 341
Urinary System
Hierarchy of Structural Organization
Organism An individual human, animal, plant,
etc…… Made up all of the organ systems Work together to sustain life
Anatomical Directions
Anatomical positionRegions Axial vs. Appendicular
Anatomical Directions-It’s all Relative! Anterior (ventral) vs. Posterior (dorsal) Medial vs. Lateral Superior (cranial) vs. Inferior (caudal) Superficial vs. Deep Proximal vs. Distal
Anatomical Planes Frontal = Coronal Transverse = Horizontal = Cross Section Sagittal Pg 5
Anterior – (ventral)
Closer to the front surface of the body
Posterior – (dorsal)
Closer to the rear surface of the body
Frontal Plane
Medial –
Lying closer to the midline
Lateral –
Lying further away from the midline
Sagittal Plane
Superior – (cranial)
Closer to the head in relation to the entire body
(More General)
Inferior – (caudal)
Away from the head or towards the lower part of the body
Horizontal Plane
Superficial –
Towards the surface
Deep –
Away from the surface
Surface of body or organ
Proximal –
Closer to the origin of a body part
(More Specific)
Distal –
Further away from the origin of a body part
Origin of a structure
Reference Point
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
Tissues: groups of cells closely associated that have a similar structure and perform a related function
Four types of tissue Epithelial = covering/lining Connective = support Muscle = movement Nervous = control
Most organs contain all 4 typesTissue has non-living extracellular material between its cells
EPITHELIAL TISSUE: sheets of cells cover a surface or line a cavity
Functions Protection Secretion Absorption Ion Transport
Characteristics of Epithelium
Cellularity Composed of cells
Specialized contacts Joined by cell junctions
Polarity Apical vs. Basal surfaces differ
Supported by connective tissueAvascularInnervatedHighly regenerative
Classification of Epithelium-based on number of layers and cell shape
Layers Simple Stratified
Stratified layers characterized by shape of apical layer
Psuedostratified
Shapes Squamous Cuboidal Columnar Transitional
Types of Epithelium
Simple squamous (1 layer) Lungs, blood vessels, ventral body cavity
Simple cuboidal Kidney tubules, glands
Simple columnar Stomach, intestines
Pseudostratified columnar Respiratory passages (ciliated version)
Stratified squamous (>1 layer) Epidermis, mouth, esophagus, vagina Named so according to apical cell shape Regenerate from below Deep layers cuboidal and columnar
Transitional (not shown) Thins when stretches Hollow urinary organs
All histology pictures property of BIOL 1010 Lab
Special Epithelium
Endothelium Simple squamous epithelium that lines
vessels e.g. lymphatic & blood vessel
Mesothelium Simple squamous epithelium that forms the
lining of body cavities e.g. pleura, pericardium, peritoneum
Features of Apical Surface of EpitheliumMicrovilli: (ex) in small intestine
Finger-like extensions of the plasma membrane of apical epithelial cell
Increase surface area for absorption
Cilia: (ex) respiratory tubes
Whip-like, motile extension of plasma membrane
Moves mucus, etc. over epithelial surface 1-way
Features of Lateral Surface of Epithelium
Cells are connected to neighboring cells via: Contour of cells-wavy contour fits together Cell Junctions (3 common)
Desmosomes Proteins hold cells together to maintain integrity of tissue
Tight Junctions Plasma membrane of adjacent cells fuse, nothing passes
Gap junction Proteins allow small molecules to pass through
Features of the Basal Surface of Epithelium
Basement membrane Sheet between the epithelial and connective
tissue layers Attaches epithelium to connective tissue below Made up of:
Basal lamina: thin, non-cellular, supportive sheet made of proteins
Superficial layer Acts as a selective filter Assists epithelial cell regeneration by moving new cells
Reticular fiber layer Deeper layer Support
Glands
Epithelial cells that make and secrete a productProducts are water-based and usually contain proteinsClassified as: Unicellular vs. multicellular Exocrine vs. Endocrine
Page 138
Glands: epithelial cells that make and secrete a water-based substance w/proteins
Exocrine Glands Secrete substance onto body surface
or into body cavity Activity is local Have ducts Unicellular or Multicellular (ex) goblet cells, salivary, mammary,
pancreas, liver
Glands: epithelial cells that make and secrete a water-based substance w/proteins
Endocrine Glands Secrete product into blood stream Either stored in secretory cells or in
follicle surrounded by secretory cells Hormones travel to target organ to
increase response (excitatory) No ducts (ex) pancreas, adrenal, pituitary,
thyroid
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
4 Types of Connective Tissue
1) Connective Tissue Proper
2) Cartilage3) Bone Tissue4) Blood
Connective Tissue (CT): most abundant and diverse
tissue
Four Classes Functions include connecting, storing & carrying nutrients, protection, fight infection CT contains large amounts of non-living extracellular matrixContains a variety of cells and fibers Some types vascularized All CT originates from mesenchyme Embryonic connective tissue
Fibers in Connective Tissue
Fibers For Support Reticular:
form networks for structure & support (ex) cover capillaries
Collagen: strongest, most numerous, provide tensile strength (ex) dominant fiber in ligaments
Elastic: long + thin, stretch and retain shape (ex) dominant fiber in elastic cartilage
Components of Connective Tissue
Fibroblasts: cells that produce all fibers in CT produce + secrete protein subunits to make them produce ground matrix
Interstitial (Tissue) Fluid derived from blood in CT proper medium for nutrients, waste + oxygen to travel to
cells found in ground matrix
Ground Matrix (substance): part of extra-cellular material that holds and absorbs
interstitial fluid Made and secreted by fibroblasts jelly-like with sugar & protein molecules
1) Connective Tissue Proper Two kinds: Loose CT & Dense CT Functions
Support and bind to other tissue Hold body fluids Defends against infection Stores nutrients as fat
Each function performed by different kind of fibers and cells in specific tissue
Defense from Infection
Areolar tissue below epithelium is body’s first defenseCells travel to CT in blood Macrophages-eat foreign particles Plasma cells-secrete antibodies, mark
molecules for destruction Mast cells-contain chemical mediators for
inflammation response White Blood Cells = neutrophils,
lymphocytes, eosinophils-fight infectionGround substance + cell fibers-slow invading microorganisms
Loose CT Proper
Areolar CT All types of fibers present All typical cell types present Surrounds blood vessels and nerves
Specialized Loose CT Proper
Adipose tissue Loaded with adipocytes, highly vascularized,
high metabolic activity Insulates, produces energy, supports Found in hypodermis under skin
Reticular CT Contains only reticular fibers Forms caverns to hold free cells, forms
internal “skeleton” of some organs Found in bone marrow, holds blood cells,
lymph nodes, spleen
Dense/Fibrous Connective Tissue
Contains more collagen Can resist extremely strong pulling forcesRegular vs. Irregular Regular-fibers run same direction, parallel to pull
(eg) fascia, tendons, ligaments Irregular-fibers thicker, run in different directions
(eg) dermis, fibrous capsules at ends of bones
Dense regular
Dense irregular
Components of CT Proper Summarized
Cells Matrix
Fibroblasts Gel-like ground substance
Defense cells-macrophages-white blood cells
Collagen fibersReticular fibersElastic fibers
Adipocytes
2) CartilageChondroblasts produce cartilageChondrocytes mature cartilage cells
Reside in lacunae
More abundant in embryo than adultFirm, FlexibleResists compression
(eg) trachea, meniscus
Avascular (chondrocytes can function w/ low oxygen)
NOT InnervatedPerichondrium
dense, irregular connective tissue around cartilage growth/repair of cartilage resists expansion during compression of cartilage
Cartilage in the Body
Three types: Hyaline
most abundant fibers in matrix support via flexibility/resilience (eg) at limb joints, ribs, nose
Elastic many elastic fibers in matrix
too great flexibility (eg) external ear, epiglottis
Fibrocartilage resists both compression and
tension (eg) meniscus, annulus
fibrosus
Components of Cartilage Summarized
Cells Matrix
Chondrocytes Gel-like ground substance
Chondroblasts(in growing cartilage)
Lots of water
Fibroblasts Some have collagen and elastic fibers
3) Bone Tissue: (a bone is an organ)
Well-vascularized Function: support (eg) pelvic bowl, legs protect (eg) skull, vertebrae mineral storage (eg) calcium, phosphate
(inorganic component) movement (eg) walk, grasp objects blood-cell formation (eg) red bone marrow
Bone TissueOsteoblasts
Secrete organic part of bone matrixOsteocytes
Mature bone cells Sit in lacunae Maintain bone matrix
Osteoclasts Degrade and reabsorb bone
Periosteum External layer of CT that surrounds bone
Outer: Dense irregular CT Inner: Osteoblasts, osteoclasts
Endosteum Internal layer of CT that lines cavities and covers trabeculae Contains osteoblasts and osteoclasts
academic.kellogg.cc.mi.us/.../skeletal.htm
Compact Bone
External layerOsteon (Haversian system)
Parallel to the long axis of the bone Groups of concentric tubules (lamella) Lamella = layer of bone matrix where all fibers run in
the same direction Adjacent lamella fibers run in opposite directions
Haversian Canal runs through center of osteon Contains blood vessels and nerves Connected to each other by perforating (Volkman) canals
Interstitial lamellae fills spaces and forms periphery
www.mc.vanderbilt.edu/.../CartilageandBone03.htm
Spongy bone (cancellous bone): internal layer
Trabeculae: small, needle-like pieces of bone form honeycomb
each made of several layers of lamellae + osteocytes no canal for vessels space filled with bone marrow not as dense, no direct stress at bone’s center
Bone Anatomy: Spongy bone
Shapes of BonesFlat = skull, sternum, clavicle
Irregular = pelvis, vertebrae
Short = carpals, patella
Long = femur, phalanges, metacarpals,
humerus
Anatomy of a Long Bone
Diaphysis Medullary Cavity Nutrient Artery & Vein
2 Epiphyses Epiphyseal Plates Epiphyseal Artery & Vein
Periosteum Does not cover epiphyses
Endosteum Covers trabeculae of spongy bone Lines medullary cavity of long bones
training.seer.cancer.gov/.../illu_long_bone.jpg
2 Types of Bone Formation
Intramembranous Ossification Membrane bones: most skull bones and clavicle Osteoblasts in membrane secrete osteoid that
mineralizes
Endochondral Ossification: All other bones Begins with a cartilaginous model Cartilage calcifies Medullary cavity is formed by action of osteoclasts Epiphyses grow and eventually calcify
Epiphyseal plates remain cartilage for up to 20 years
Bone Growth & RemodelingGROWTH Appositional Growth = widening of bone
Bone tissue added on surface by osteoblasts of periosteum
Medullary cavity maintained by osteoclasts Lengthening of Bone
Epiphyseal plates enlarge by chondroblasts Matrix calcifies (chondrocytes die and disintegrate) Bone tissue replaces cartilage on diaphysis side
REMODELING Due to mechanical stresses on bones, their tissue
needs to be replaced Osteoclasts-take up bone ( = breakdown) release Ca2++ ,
PO4 to body fluids from bone Osteoblasts-form new bone by secreting osteoid
Ideally osteoclasts & osteoblasts work at the same rate!
Components of Bone Tissue Summarized
Cells Matrix
Osteblasts Gel-like ground substance calcified with inorganic salts
Fibroblasts Collagen fibers
Osteocytes
Osteoclasts
4) Blood: Atypical Connective Tissue
Function: Transports waste, gases, nutrients,
hormones through cardiovascular system Helps regulate body temperature Protects body by fighting infection
Derived from mesenchymeHematopoiesis: production of blood cells Occurs in red bone marrow In adults, axial skeleton, girdles, proximal
epiphyses of humerus and femur
Blood Cells Erythrocytes: (RBC) small, oxygen-transporting
most abundant in bloodno organelles, filled w/hemoglobinpick up O2 at lungs, transport to rest of body
Leukocytes: (WBC) complete cells , 5 types
fight against infectious microorganisms
stored in bone marrow for emergencies
*Platelets = Thrombocytes:
fragments of cytoplasm
plug small tears in vessel walls, initiates clotting
Components of Blood Summarized
Cells Matrix
Erythrocytes (red blood cells)
Plasma (liquid matrix)
Leukocytes(white blood cells)
NO fibers
*Platelets(cell fragments)
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
Muscle Tissue
Muscle cells/fibers Elongated Contain many myofilaments: Actin & Myosin
FUNCTION Movement Maintenance of posture Joint Stabilization Heat Generation
Three types: Skeletal, Cardiac, Smooth
Skeletal Muscle Tissue(each skeletal muscle is an organ)
Cells Long and cylindrical, in bundles Multinucleate Obvious Striations
Skeletal Muscles-VoluntaryConnective Tissue Components:
Endomysium-surrounds fibers Perimysium-surrounds bundles Epimysium-surrounds the muscle
Attached to bones, fascia, skinOrigin & Insertion
academic.kellogg.cc.mi.us/.../muscular.htm
Cardiac Muscle
Cells Branching, chains of cells Single or Binucleated Striations Connected by Intercalated discs
Cardiac Muscle-InvoluntaryMyocardium-heart muscle Pumps blood through vessels
Connective Tissue Component Endomysium: surrounding cells www.answers.co
m
Smooth Muscle Tissue
CellsSingle cells, uninucleateNo striations
Smooth Muscle-Involuntary2 layers-opposite orientation (peristalsis)
Found in hollow organs, blood vesselsConnective Tissue Component
Endomysium: surrounds cells
4 Types of Tissue
1)Epithelium
2)Connective
3)Muscle
4)Nervous
Nervous Tissue
Neurons: specialized nerve cells conduct impulses Cell body, dendrite, axon
Characterized by: No mitosis (cell replication) Longevity High metabolic rate
www.morphonix.com
Nervous Tissue: control
Support cells (= Neuroglial): nourishment, insulation, protection Satellite cells-surround cell bodies within ganglia Schwann cells-surround axons (PNS) Microglia-phagocytes Oligodendrocytes-produce myelin sheaths
around axons Ependymal cells-line brain/spinal cord, ciliated,
help circulate CSF
Brain, spinal cord, nerves
Integumentary System
Functions Protection
Mechanical, thermal, chemical, UV Cushions & insulates deeper organs Prevention of water loss Thermoregulation Excretion
Salts, urea, water Sensory reception
Microanatomy - Layers of the Skin
Epidermis Epithelium
Dermis Connective tissue
Hypodermis / subcutis Loose connective tissue Anchors skin to bone or muscle
Skin Appendages = outgrowths of epidermis Hair follicles Sweat and Sebaceous glands Nails
www.uptodate.com/.../Melanoma_anatomy.jpg
Cell Layers of the Epidermis
Stratum corneum Dead keratinocytes
Stratum lucidum Only in “thick” skin Dead keratinocytes
Stratum granulosum Water proofing
Stratum spinosum Resists tears and tension
Stratum basale Sensory receptors Melanocytes Keratinocytes (in all layers) 15minbeauty.blogspot.com
Layers of the DermisHighly innervatedHighly vascularizedCollagen & Elastic fibers2 layers:
Papillary layer (20%) Areolar CT Collagen & Elastic fibers Innervation Hair follicles
Reticular layer (80%) Dense irregular CT Glands
sebum 2.5 million sweat glands!!
Smooth muscle fibers Innervation
www.uptodate.com/.../Melanoma_anatomy.jpg
Hypodermis
Also called superficial fasciaAreolar & Adipose Connective TissueFunctions Store fat Anchor skin to muscle, etc. Insulation
Structure of Tubular Organs
LUMENTunica Mucosa
Lamina epithelialis Lamina propria Lamina muscularis mucosa
Tunica SubmucosaTunica Muscularis
Inner circular Outer longitudinal
Tunica Adventitia / Serosa Adventitia – covers organ directly Serosa – suspends organ in the peritoneal cavity