1 / 52

CHAPTER 4

CHAPTER 4. TISSUE: THE LIVING FABRIC. INTRODUCTION TO TISSUE. TISSUES ARE GROUPS OF CELLS THAT ARE SIMILAR IN STRUCTURE AND FUNCTION 4 PRIMARY TISSUE TYPES: EPITHILIAL (COVERING), CONNECTIVE(SUPPORT), NERVOUS (CONTROL), AND MUSCULAR (MOVEMENT). EPITHELIAL TISSUE. FEATURES OF EPITHELIA.

liang
Download Presentation

CHAPTER 4

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CHAPTER 4 TISSUE: THE LIVING FABRIC

  2. INTRODUCTION TO TISSUE • TISSUES ARE GROUPS OF CELLS THAT ARE SIMILAR IN STRUCTURE AND FUNCTION • 4 PRIMARY TISSUE TYPES: EPITHILIAL (COVERING), CONNECTIVE(SUPPORT), NERVOUS (CONTROL), AND MUSCULAR (MOVEMENT)

  3. EPITHELIAL TISSUE

  4. FEATURES OF EPITHELIA • AN EPITHELIUM IS A SHEET OF CELLS THAT COVERS A BODY SURFACE OR LINES A CAVITY • EPITHELIUM OCCURS IN THE BODY AS COVERING OR LINING EPITHELIUM, AND AS GLANDULAR EPITHELIUM

  5. SPECIAL CHARACTERISTICS OF EPITHELIUM • COMPOSED OF CLOSELY PACKED CELLS WITH LITTLE EXTRACELLULAR MATERIAL BETWEEN • ADJACENT EPITHELIAL CELLS ARE BOUND TOGETHER BY SPECIALIZED CONTACTS SUCH AS DESMOSOMES AND TIGHT JUCTIONS • EXHIBITS POLARITY – HAS APICAL SURFACE (FREE) AND BASAL SURFACE (ATTACHED)

  6. SPECIAL CHARACTERISTICS OF EPITHELIUM • SUPPORTED BY THE UNDERLYING CONNECTIVE TISSUE • INNERVATED BUT AVASCULAR • HAS A HIGH REGENERATION CAPACITY

  7. CLASSIFICATION OF EPITHELIA

  8. EPITHELIAL TISSUE HAS TWO NAMES • FIRST NAME - # OF LAYERS PRESENT, SIMPLE (ONE) OR STRATIFIED (MORE THAN ONE) • SECOND NAME – DESCRIBES THE SHAPE OF THE CELLS

  9. SIMPLE EPITHELIA • MOSTLY CONCERNED WITH ABSORPTION, SECRETION, AND FILTRATION • SIMPLE SQUAMOUS EP. – SINGLE LAYER OF FISH SCALE-SHAPED CELLS • SIMPLE CUBOIDAL EP. – SINGLE LAYER OF CUBE SHAPED CELLS FORMING THE SMALLEST DUCTS OF GLANDS AND MANY KIDNEY TUBULES

  10. SIMPLE COLUMNAR EP. – SINGLE LAYER OF COLUMN SHAPED CELLS THAT LINE THE DIGESTIVE TRACT • PSEUDOSTRATIFIED COLUMNAR EP. – CONTAINS CELLS OF VARYING HEIGHTS GIVING THE FALSE IMPRESSION OF THE PRESENCE OF MANY LAYERS

  11. STRATIFIED EPITHELIA • MAIN FUNCTION IS PROTECTION • STRATIFIED SQUAMOUS EP. – COMPOSED OF SEVERAL LAYERS WITH THE CELLS ON THE FREE SURFACE BEING SQUAMOUS SHAPED AND THE UNDERLYING CELLS BEING CUBOIDAL OR COLUMNAR SHAPED

  12. STRATIFIED CUBOIDAL EP. – RARE, FOUND MOSTLY IN THE DUCTS OF SOME OF THE LARGER GLANDS • STRATIFIED COLUMNAR EP. – FOUND IN LIMITED DISTRIBUTION WITH SMALL AMOUNTS IN THE PHARNYX, MALE URETHRA, AND LINING SOME GALNDULAR DUCTS • TRANSITIONAL EP. – FORMS THE LINING OF THE HOLLOW ORGANS OF THE URINARY SYSTEM THAT STRETCH AS THEY FILL

  13. GLANDULAR EPITHELIA • ENDOCRINE GLANDS – DUCTLESS GLANDS THAT SECRETE HORMONES BY EXOCYTOSIS DIRECTLY INTO THE BLOOD OR LYMPH • EXOCRINE GLANDS – HAVE DUCTS, SECRETE THEIR PRODUCT ONTO A SURFACE OR INTO BODY CAVITIES

  14. CONNECTIVE TISSUE

  15. FUNCTIONS OF CONNECTIVE TISSUE • BINDING AND SUPPORT • PROTECTION • INSULATION • TRANSPORTATION

  16. COMMON CHARACTERISTICS OF CT • ALL CT ARISES FROM AN EMBRYONIC TISSUE CALLED MESENCHYME • CT RANGES FROM AVASCULAR TO HIGHLY VASCULARIZED • CT IS COMPOSED MAINLY OF NONLIVING EXTRACELLULAR MATRIX THAT SEPARATES THE CELLS OF THE TISSUE

  17. STRUCTURAL ELEMENTS OF CT • GROUND SUBSTANCE – THE UNSTRUCTURED MATERIAL THAT FILLS THE SPACE BETWEEN THE CELLS AND CONTAINS THE FIBERS • FIBERS OF THE CT PROVIDE SUPPORT: A)COLLAGEN FIBERS ARE EXTREMEMLY STRONG AND PROVIDE HIGH TENSILE STRENGTH, B)ELASTIC FIBERS – CONTAIN ELASTIN WHICH ALLOWS THEM TO BE STRETCHED AND TO RECOIL, C)RETICULAR FIBERS – FINE, COLLAGENOUS FIBERS THAT FORM NETWORKS • EACH MAJOR CLASS OF CT HAS A FUNDAMENTAL CELL TYPE THAT EXISTS IN IMMATURE AND MATURE FORMS

  18. TYPES OF CONNECTIVE TISSUE • MESENCHYME – FORMS DURING EARLY WEEKS OF EMBRYONIC DEVEL. FROM THE MESODERM AND EVENTUALLY DIFFERENTIATES INTO ALL OTHER CT.

  19. TYPES CONT. • LOOSE CT – 3 TYPES: AREOLAR, ADIPOSE, AND RETICULAR • AREOLAR – SRVES TO BIND BODY PARTS TOGETHER WHILE ALLOWING THEM TO MOVE FREELY, WRAPS SMALL BLOOD VESSELS AND NERVES, SURROUNDS GLANDS, AND FORMS SUBCUTANEOUS TISSUE • ADIPOSE – RICHLY VASCULARIZED, FUNCTIONS IN NUTRIENT STORAGE, PROTECTION, AND INSULATION • RETICULAR – FORMS INTERNAL FRAMEWORK OF LYMPH NODES, THE SPLEEN, AND BONE MARROW

  20. TYPES CONT. • DENSE CT – 2 TYPES: • DENSE REGULAR CT – CLOSELY PACKED BUNDLES OF COLLAGEN FIBERS RUNNING IN THE SAME DIRECTION, MAKES UP TENDONS AND LIGAMENTS • DENSE IRREGULAR CT – THICK BUNDLES OF COLLAGEN ARRANGED IN IRREGULAR FASHION, FOUND IN THE DERMIS

  21. TYPES CONT. • CARTILAGE – LACKS NERVE FIBERS AND IS AVASCULAR, 3 TYPES: • HYALINE – MOST ABUNDANT, PROVIDES FIRM SUPPORT WITH SOME PLIABILITY • ELASTIC – FOUND WHERE STRENGTH AND EXCEPTIONAL STRETCHABILITY ARE NEEDED, SUCH AS EXTERNAL EAR • FIBROCARTILAGE – FOUND WHERE STRONG SUPPORT AND THE ABILITY TO WITHSTAND HEAVY PRESSURE ARE REQUIRED SUCH AS INTERVERTEBRAL DISKS

  22. TYPES CONT. • BONE (OSSEOUS TISSUE) – SUPPORTS AND PROTECTS BODY STRUCTURES DUE TO ITS HARDNESS, WHICH IS DETERMINED BY THE ADDITIONAL COLLAGEN FIBERS AND CALCIUM SALTS FOUND IN THE EXTRACELLUALR MATRIX • BLOOD – CLASSIFIED AS A CT BECAUSE IT DEVELOPED FROM MESENCHYME, CONSISTS OF BLOOD CELLS AND PLASMA PROTEINS SURROUNDED BY BLOOD PLASMA

  23. COVERING AND LINING MEMBRANES • CUTANEOUS MEMBRANE, OR SKIN, IS AN ORGAN SYSTEM CONSISTING OF KERATINIZED SQUAMOUS EPITHELIUM FIRMLY ATTACHED TO A THICK LAYER OF DENSE IRREGULAR CONNECTIVE TISSUE

  24. MEMBRANES CONT. • MUCOUS MEMBRANES LINE BODY CAVITIES THAT OPEN TO THE EXTERIOR AND CONTAIN EITHER STRATIFIED SQUAMOUS OR SIMPLE COLUMNAR EPITHELIA

  25. MEMBRANES CONT. • SEROUS MEMBRANES CONSIST OF SIMPLE SQUAMOUS EPITHELIUM RESTING ON A THIN LAYER OF LOOSE CONNECTIVE (AREOLAR) TISSUE

  26. NERVOUS TISSUE • NT IS THE MAIN COMPONENT OF THE NERVOUS SYSTEM, WHICH REGULATES AND CONTROLS BODY FUNCTIONS • 2 TYPES OF CELLS: • NEURONS – SPECIALIZED CELLS THAT GENERATE AND CONDUCT ELECTRICAL IMPULSES • SUPPORTING CELLS – NONCONDUCTIVE CELLS THAT SUPPORT, INSULATE, AND PROTECT THE NEURONS

  27. MUSCLE TISSUE • MT ARE HIGHLY CELLULAR, WELL VASCULARIZED AND ARE RESPONSIBLE FOR MOVEMENT • 3 TYPES: • SKELETAL – ATTACHES TO THE SKELETON AND PRODUCES VOLUNTARY BODY MOVEMENT • CARDIAC MUSCLE – RESPONSIBLE FOR THE INVOLUNTARY MOVEMENT OF THE HEART • SMOOTH MUSCLE – FOUND IN THE WLLS OF THE HOLLOW ORGANS

  28. TISSUE REPAIR • OCCURS IN 2 WAYS – REGENERATION AND FIBROSIS • 3 STEPS – 1. INFLAMMATION PREPARES THE AREA FOR THE REPAIR PROCESS, 2. ORGANIZATION RESTORES THE BLOOD SUPPLY, 3. REGENERATION AND FIBROSIS EFFECT PERMANENT REPAIR • THE GENERATIVE CAPACITY OF TISSUES VARIES WIDELY AMONG TISSUE TYPES

  29. DEVELOPMENTAL ASPECTS OF TISSUES • EMBRYONIC AND FETAL DEVELOPMENT – PRIMARY GERM LAYER FORMATION IS ONE OF THE FIRST EVENTS IN EMBRYONIC DEVELOPMENT • ECTODERM – THE MOST SUPERFICIAL OF THE LAYERS • MESODERM – MIDDLE LAYER • ENDODERM – DEEPEST LAYER • THE PRIMARY GERM LAYERS SPECIALIZE TO FORM THE FOUR PRIMARY TISSUES

  30. WITH INCREASING AGE, EPITHELIA BECOME THIN, COLLAGEN FIBERS DECREASE, BONE, MUSCLE, AND NERVOUS TISSUE ATROPHY

More Related