human anatomy (biol 1010) e. goffe office 1132f (providence)
DESCRIPTION
Hierarchy of the Body Molecules made of chemicals (4 macromolecules in body) carbohydrates, lipids, proteins, nucleic acids Cells made of molecules cells and organelles Tissue made of cells epithelial, connective, muscular, nervous Organs made of tissues made of >1 type of tissue Systems made of organs 11 systems in human body Organisms made of systemsTRANSCRIPT
Human Anatomy(BIOL 1010)
E. [email protected] 1132F (Providence)
What is Anatomy?Anatomy (= morphology): study of body’s structurePhysiology: study of body’s functionStructure 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 the Body Moleculesmade of chemicals (4 macromolecules in body) carbohydrates, lipids, proteins, nucleic acids
Cellsmade of molecules cells and organelles
Tissuemade of cells epithelial, connective, muscular, nervous
Organsmade of tissues made of >1 type of tissue
Systemsmade of organs 11 systems in human body
Organismsmade of systems
Anatomical DirectionsAnatomical 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
Embryology: growth and development
of the body before birth38 weeks from conception to birthPrenatal period Embryonic: weeks 1-8 Fetal: weeks 9-38
Basic adult body plan shows by 2nd month Skin = epidermis, dermis Outer body wall=muscle, vertebral column and
spinal cord Body cavity and digestive tubes Kidney and gonads Limbs=skin, muscle, bone
Weeks 5-8 and Fetal Period Second month, tadpole person Tail disappears Head enlarges Extremities form (day 28, limb buds appear) Eyes, nose, ears form Organs in placeFetal Period Rapid growth and maturation Organs grow and increase in complexity
& competence
4 Types of Tissue
1)Epithelium2)Connective3)Muscle4)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 = controlMost 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 (tissue type #1)
Functions Protection Secretion Absorption Ion Transport Slippery Surface
Characteristics of Epithelium
CellularitySpecialized ContactsPolarity Apical vs. Basal
Supported by Connective TissueAvascularInnervatedRegenerative
Classification of Epithelium-based on number of layers and cell shapeLayers Simple Stratified Psuedostratified
Stratified layers characterized by shape of apical layerShapes Squamous Cuboidal Columnar Transitional
Features of Apical Surface of Epithelium
Microvilli: (ex) in small intestine Finger-like extensions of the plasma
membrane of apical epithelial cell Increase surface area for absorptionCilia: (ex) respiratory tubes Whip-like, motile extension of plasma
membrane Moves mucus, etc. over epithelial surface
1-wayFlagella: (ex) spermatoza Extra long cilia Moves cell
Features of Lateral Surface of Epithelium
Cells are connected to neighboring cells via: Proteins-link cells together, interdigitate Contour of cells-wavy contour fits together Cell Junctions
Desmosomes-adhesive spots on lateral sides linked by proteins/filaments, holds tissues together
Tight Junctions-at apical area, plasma membrane of adjacent cells fuse, nothing passes
Gap junction- spot-like junction occurring anywhere made of hollow cylinders of protein, lets small molecules pass
Features of the Basal Surface of Epithelium
Basement membrane = Sheet between the epithelial and connective tissue layers Attaches epithelium to connective tissue below 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 water-based substance w/proteins
Exocrine Glands Secrete substance onto body surface or
into body cavity Have ducts (simple vs. compound) Unicellular (goblet cells) or Multicellular
(tubular, alveolar, tubuloalveolar) (ex) salivary, mammary, pancreas, liver
Glands: epithelial cells that make and secrete a water-based substance w/proteinsEndocrine 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 Connective Tissue
1) Connective Tissue Proper
2) Cartilage3) Bone Tissue4) Blood
Connective Tissue (CT): most abundant and diverse tissue
(tissue type #2)
Four Classes Functions include connecting, storing & carrying nutrients, protection, fight infection CT contains large amounts of non-living extracellular matrix Some types vascularized All CT originates from mesenchyme
1) Connective Tissue Proper
Two kinds: Loose CT & Dense CTPrototype: Loose Areolar Tissue Underneath epithelial tissue Functions
Support and bind to other tissue Hold body fluids Defends against infection Stores nutrients as fat
Each function performed by different kind of fiber in tissue
Fibers in Connective TissueFibers 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
In Connective Tissue ProperFibroblasts: cells that produce all fibers in CT, produce + secrete protein subunits to make them, produce ground matrixInterstitial (Tissue) Fluid: derived from blood in CT proper; medium for nutrients, waste + oxygen to travel to cells; found in ground matrixGround Matrix (substance): part of extra-cellular material that holds and absorbs interstitial fluid, jelly-like with sugar & protein molecules
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
Specialized Loose CT ProperAdipose tissue-loaded with adipocytes, highly vascularized, high metabolic activity Insulates, produces energy, supports
(eg) in hypodermis under skin
Reticular CT-contains only reticular fibers Forms caverns to hold free cells
(eg) bone marrow, holds blood cells Forms internal “skeleton” of some organs
(eg) 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
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 cellsMore abundant in embryo than adultFirm, FlexibleResists compression
(eg) trachea, meniscus80% waterAvascular (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 fibrils 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
Some have collagen and elastic fibers
3) Bone Tissue:(a bone is an organ)
Functions: 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
Components of Bone
Matrix Mineralized with hydroxyappetite
Cells Osteoblasts: secrete organic part of bone matrix Osteocytes: mature bone cells, maintain bone matrix
Connective Tissue Proper Periosteum: external layer of CT surrounds bone Endosteum: internal layer of CT lines cavities and covers
trabeculae Both contain osteoblasts and osteoclasts
Bone is well-vascularized, highly innervated
Compact bone: dense, external layerHaversian system = osteon long, cylindrical structures run parallel to long axis of
bone within each osteon, groups of concentric tubes (lamella) Lamella: layer of bone matrix all fibers run in same
direction fibers on each lamella runs in opposite directions to one near it
Haversian canal-runs through center of osteon, contain blood vessels and nerves
Interstitial Lamella- pieces of bone matrix between osteon
Osteocytes between osteons
Bone Anatomy: Compact bone
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 BoneDiaphysis
Medullary Cavity Nutrient Art & Vein
2 Epiphyses Epiphyseal Plates Epiphyseal Art & Vein
Periosteum Outer: Dense irregular CT Inner: Osteoblasts, osteoclasts Does not cover epiphyses Attaches to bone matrix via
collagen fibersEndosteum
Osteoblasts, osteoclasts Covers trabeculae, lines medullary
cavity
2 Types of Bone FormationEndochondral Ossification: All other bones
Begins with a cartilaginous model Perichondrium becomes replaced by periosteum Cartilage calcifies Medullary cavity is formed by action of osteoclasts Epiphyses grow and eventually calcify
Epiphyseal plates remain cartilage for up to 20 years Intramembranous Ossification
Membrane bones: most skull bones and clavicle Osteoblasts in membrane secrete osteoid that mineralizes Trabeculae form between blood vessels, thickens to
become compact bone at periphery Osteocytes maintain new bone tissue Periosteum forms over it
Bone Growth & Remodeling
GROWTH 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 and osteoblasts work at the same rate!
Components of Bone Tissue Summarized
Cells Matrix
Osteocytes Gel-like ground substance calcified with inorganic salts
Osteoblasts Collagen fibers
4) Blood: Atypical Connective Tissue
Function: Transports waste, gases, nutrients,
hormones through cardiovascular system Helps regulate body temperature Protects body by fighting infectionDerived from mesenchymeHematopoiesis: production of blood cells Occurs in red bone marrow In adults, axial skeleton, girdles, proximal
epiphyses of humerus and femur
Blood CellsErythrocytes: (RBC) small, oxygen-transporting
most abundant in bloodno organelles, filled w/hemoglobinpick up O2 at lungs, transport to rest of body
Platelets = Thrombocytes: fragments of cytoplasmplug small tears in vessel walls, initiates clotting
Leukocytes: (WBC) complete cells , 5 typesfight against infectious microorganisms stored in bone marrow for emergencies
Components of Blood SummarizedCells Matrix
Erythrocytes (red blood cells)
Plasma (liquid matrix)
Leukocytes(white blood cells)
NO fibers
Platelets
Muscle Tissue (tissue type #3)
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
Cardiac MuscleCells Branching, chains of cells Single or Binucleated Striations Connected by Intercalated
discsCardiac Muscle-InvoluntaryMyocardium-heart muscle Pumps blood through vessels
Connective Tissue Component Endomysium: surrounding cells
Smooth Muscle Tissue
CellsSingle cells, uninucleateNo striations
Smooth Muscle-Involuntary2 layers-opposite orientation (peristalsis)
Lines hollow organs, blood vesselsConnective Tissue Component
Endomysium: surrounds cells
Nervous TissueNeurons: specialized nerve cells conduct impulses Cell body, dendrite, axon
Interneuron: between motor & sensory neuron in CNSCharacterized by: No mitosis (cell replication) Longevity High metabolic rate
Nervous Tissue: control
Support cells (= Glial): nourishment, insulation, protection Satellite cells-surround cell bodies
within ganglia Schwann cells-surround axons Microglia-phagocytes Oligodendrocytes-produce myelin
sheaths around axons Ependymal cells-line brain/spinal cord,
ciliated,help circulate CSFBrain, spinal cord, nerves
Neuronal Anatomy
Synapse: cell junction where neurons communicateOne direction: presynaptic neuron, postsynaptic neuronPresynaptic neuron
Synaptic vesicles fuses w/presynaptic membrane
Neurotransmitters released, diffuse across synaptic cleft, bind to postsynaptic membrane ٠Creates impulse (action potential) in that neuron
٠Cycle repeats
Integumentary System
Skin Epidermis = epithelium Dermis = connective tissue Hypodermis = connective tissueSkin Appendages = outgrowths of epidermis Hair follicles Sweat and Sebaceous glands Nails
Integumentary System
Functions Protection
Mechanical, thermal, chemical, UV Cushions & insulates deeper organs Prevention of water loss Thermoregulation Excretion
Salts, urea, water Sensory reception
Layers of the Epidermis Stratum corneum
Dead keratinocytes
Stratum lucidumDead keratinocytes
Stratum granulosumKeratinocytesTonofilamentsLamellated & keratohyaline granules
Stratum spinosumKeratinocytesTonofilamentsLangerhans cells
Stratum basaleKeratinocytesMelanocytesMerkel receptors
Dermis Highly innervated
Highly vascularizedCollagen & Elastic fibersMany cell types
FibroblastsMacrophagesMast cellsWhite blood cells
Papillary layer (20%) Areolar CT Hair follicles
Reticular layer (80%) Dense Irregular CT Glands
Sebaceous glands Sweat glands
Smooth muscle fibers
HypodermisAlso called superficial fasciaAreolar & Adipose Connective TissueFunctions Store fat Anchor skin to muscle, etc. Insulation