Chapter 5 Tissues PDF

Because learning changes everything. ® Chapter 05 Tissues Hole’s Human Anatomy & Physiology 2024 Release Charles J. Welsh, Cynthia Prentice Craver © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC...

Because learning changes everything. ® Chapter 05 Tissues Hole’s Human Anatomy & Physiology 2024 Release Charles J. Welsh, Cynthia Prentice Craver © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.  5.1 Cells Are Organized into Tissues In complex organisms, cells are organized into tissues Tissue: A group of similar cells with a common function The study of tissues is called histology. There are 4 major types of tissues in the body: Epithelial tissue Connective tissue Muscle tissue Nervous tissue © McGraw Hill, LLC 2  Table 5.1 Tissues: Four Major Tissue Types Type Function Location Distinguishing Characteristics Epithelial Protection, secretion, Cover body surface, Lack blood vessels, cells absorption, excretion cover and line readily divide, cells are internal organs, tightly packed compose glands Connective Bind, support, protect, Widely distributed Mostly have good blood fill spaces, store fat, throughout the body supply, cells are farther produce blood cells apart than epithelial cells, with extracellular matrix in between Muscle Movement Attached to bones, in Able to contract in the walls of hollow response to specific internal organs, heart stimuli Nervous Conduct impulses for Brain, spinal cord, Cells communicate with coordination, nerves each other and other body regulation, integration, parts and sensory reception © McGraw Hill, LLC 3  Table 5.2 Types of Intercellular Junctions Type Characteristics Example Tight junctions Close space between cells Cells that line the small by fusing cell membranes intestine Desmosomes Bind cells by forming “spot Cells of the outer skin layer welds” between cell membranes Gap junction Form tubular channels Muscle cells of the heart between cells that allow and digestive tract exchange of substances © McGraw Hill, LLC 4  Figure 5.1 Intercellular Junctions Access the text alternative for slide images. © McGraw Hill, LLC 5  From Science to Technology 5.1 Nanotechnology Meets the Blood-Brain Barrier Nanotechnology helps with drug delivery across the blood- brain barrier Blood-brain barrier selects which chemicals are allowed to cross; protects from toxins and chemical fluctuations Nanotechnology uses structures smaller than 100 nm in at least 1 direction, to help medications cross the blood- brain barrier Example: Anesthetics or chemotherapeutics are combined with liposomes (phospholipid bubbles) to mask portion of drug that cannot cross the barrier Example: Insulin can be inhaled in nanoparticles, instead of being injected © McGraw Hill, LLC 6  5.2 Epithelial Tissues General Characteristics of Epithelial Tissues: Cover organs and body surface Line cavities and hollow organs Make up glands Have a free surface on outside, and basement membrane on inside Lack blood vessels (avascular), and nutrients diffuse to epithelial tissue from underlying connective tissue Cells readily divide; injuries heal rapidly Cells are tightly packed Classified according to cell shape and number of cell layers Shapes: squamous (flat), cuboidal (cube-shaped), columnar (tall) Layers: simple (one layer of cells), stratified (2 or more layer of cells), or pseudostratified (appears layered, but is not) © McGraw Hill, LLC 7  Simple Squamous and Simple Cuboidal Epithelia Simple squamous epithelium: Single layer of thin, flat cells Substances pass easily through air sacs (alveoli) and capillaries Thin and delicate, can be easily damaged Found in diffusion and filtration sites Makes up walls of air sacs (alveoli) and capillaries Lines blood and lymphatic vessels Simple cuboidal epithelium: Single layer of cube-shaped cells Secretion and absorption Lines kidney tubules, thyroid follicles, ducts of some glands Covers ovaries © McGraw Hill, LLC 8  Figures 5.3 and 5.4 Simple Squamous and Simple Cuboidal Epithelia (b): Al Telser/McGraw Hill; (c): Ed Reschke (b): Victor P. Eroschenko Access the text alternative for slide images. © McGraw Hill, LLC 9  Simple Columnar and Pseudostratified Columnar Epithelia Simple columnar epithelium: Single layer of elongated cells Nuclei usually at same level, near basement membrane. Sometimes have microvilli, cilia, goblet cells (secrete mucus) Secretion and absorption Lines uterus, stomach, intestines Pseudostratified columnar epithelium: Single layer, but appears layered Nuclei at 2 or more levels Cells vary in shape, but all reach basement membrane Often has cilia, goblet cells Protection from infection Lines respiratory passageways © McGraw Hill, LLC 10  Figures 5.5 and 5.6 Simple Columnar Epithelium and Microvilli (b): Victor P. Eroschenko Fawcett, Hirokawa, Heuser/Science Source Access the text alternative for slide images. © McGraw Hill, LLC 11  Figure 5.7 Pseudostratified Columnar Epithelia (b): Dennis Strete/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 12  Stratified Squamous and Stratified Cuboidal Epithelia Stratified squamous epithelium: Many cell layers; thick Protective layer Outermost cells are squamous, deeper cells are cuboidal New cells produced in deep layers, push older cell toward free surface Outer layer of skin, called the epidermis, is keratinized Lines oral cavity, vagina, anal canal Stratified cuboidal epithelium: 2 to 3 layers of cube-shaped cells More protection than 1 layer Lines ducts of mammary, sweat, and salivary glands, and pancreas © McGraw Hill, LLC 13  Figures 5.8 and 5.9 Stratified Squamous and Stratified Cuboidal Epithelia Both (b): Al Telser/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 14  Stratified Columnar and Transitional Epithelia Stratified columnar epithelium: Several layers of cells Top layer of elongated cells Cube-shaped cells in deeper layers Lines part of male urethra, ducts of exocrine glands Transitional epithelium(uroepithelium): Many cell layers Cube-shaped and elongated cells Changes shape and appearance with increased tension; stretches Forms barrier and lining that can expand Lines urinary bladder, ureters, and part of urethra © McGraw Hill, LLC 15  Figures 5.10 and 5.11 Stratified Columnar and Transitional Epithelia (b): Al Telser/ McGraw Hill (b, d): Ed Reschke Access the text alternative for slide images. © McGraw Hill, LLC 16  Table 5.3 Epithelial Tissues Type Description Function Location Simple squamous Single layer, flattened Filtration, diffusion, Air sacs of lungs, walls of capillaries, epithelium cells osmosis, covers surface linings of blood and lymph vessels, part of the membranes lining body cavities and covering viscera Simple cuboidal Single layer, cube- Protection, secretion, Surface of ovaries, linings of kidney epithelium shaped cells absorption tubules, and linings of ducts of certain glands Simple columnar Single layer, elongated Protection, secretion, Linings of uterus, stomach, and epithelium cells absorption intestines Pseudostratified Single layer, elongated Protection, secretion, Linings of respiratory passages columnar epithelium cells movement of mucus and substances Stratified squamous Many layers, top cells Protection Superficial layer of skin and linings of epithelium flattened oral cavity, vagina, and anal canal Stratified cuboidal 2 or 3 layers, cube- Protection Linings of ducts of mammary glands, epithelium shaped cells sweat glands, salivary glands, and pancreas Stratified columnar Top layer of elongated Protection, secretion Part of the male urethra and lining of epithelium cells, lower layers of larger ducts of excretory glands cube-shaped cells Transitional Many layers of cube- Stretchability, protection Inner lining of urinary bladder and epithelium shaped and elongated linings of ureters and part of urethra cells © McGraw Hill, LLC 17  Glandular Epithelium Glandular Epithelium: Composed of cells that produce and secrete substances into ducts or body fluids Two types of glands in the body: Endocrine glands secrete into tissue fluid or blood Exocrine glands secrete into ducts that open onto a surface Two structural types of exocrine glands: Unicellular: Composed of one cell, such as a goblet cell (secretes mucus). Multicellular: Composed of many cells; can be simple or compound; examples: sweat and salivary glands © McGraw Hill, LLC 18  Features of Exocrine Glands Structural types of exocrine glands: Simple: duct does not branch Compound: duct branches before it reaches secretory portion Tubular: consist of epithelial-lined tubes Alveolar: terminal portions form sac-like dilations Types of glandular secretion: Merocrine glands: Secrete fluid products by exocytosis; salivary and sweat glands, pancreas Apocrine glands: Lose small part of cell during secretion; mammary and ceruminous glands Holocrine glands: Release entire cells filled with product; sebaceous glands © McGraw Hill, LLC 19  Figure 5.12 Structural Types of Exocrine Glands Access the text alternative for slide images. © McGraw Hill, LLC 20  Table 5.4 Types of Exocrine Glands Type Characteristics Example Unicellular glands A single secretory cell Mucous-secreting cell (see Figure 5.5) Multicellular glands Glands that consist of many cells Simple glands Glands that communicate with the surface by means of ducts that do not branch before reaching the secretory portion 1. Simple tubular gland Straight tube-like gland that opens directly onto Intestinal glands of small surface intestine (see Figure 17.3) 2. Simple branched tubular Branched, tube-like gland; duct short or absent Gastric glands (see Figure gland 17.19) 3. Simple coiled tubular gland Long, coiled, tube-like gland; long duct Merocrine (sweat) glands of skin (see Figures 6.11 and 6.12) 4. Simple branched alveolar Secretory portions of gland expand into saclike Sebaceous gland of skin gland compartments along duct (see Figure 5.14) Compound glands Glands that communicate with surface by means of ducts that branch repeatedly before reaching the secretory portion 1. Compound tubular gland Secretory portions are tubules extending from Bulbourethral glands of branches of branches that combine into one male (see Figure 22.4) duct 2. Compound alveolar gland Secretory portions are irregularly branched Mammary glands (see tubules with numerous saclike outgrowths Figure 23.28) © McGraw Hill, LLC 21  Figure 5.13 Exocrine Glandular Secretions Access the text alternative for slide images. © McGraw Hill, LLC 22  5.3 Connective Tissues General characteristics of connective tissues: Most abundant tissue type by weight Cells are farther apart than epithelial cells Contain abundant extracellular matrix between cells, consisting of protein fibers and a ground substance Consistency varies from fluid to solid Categories: Connective tissue proper Specialized connective tissues Most have good blood supply, so are well-nourished Most cells have ability to divide Contain fixed cells, which remain in one place, and wandering cells, such as macrophages, which move throughout tissues © McGraw Hill, LLC 23  Connective Tissues: Functions Functions of connective tissues: Bind structures together Provide support and protection Serve as frameworks Fill spaces Store fat Produce blood cells Protect against infections Help repair tissue damage © McGraw Hill, LLC 24  Clinical Application 5.1 The Body’s Glue: The Extracellular Matrix Functions of normal extracellular matrix (ECM): Scaffolding that organizes and anchors cells into tissues Relays chemical signals that control cell division and differentiation, tissue repair, cell migration. Cancer: Can convert fibroblasts into myofibroblasts, which take on characteristics of cancer cells; also loosens fibroblast connections, allowing migration of converted fibroblasts and spreading cancer Liver Fibrosis: Collagen deposition increases, and ECM now exceeds its normal 3% of organ. Damaging agents evoke normal inflammatory response, but if it continues too long, it can block connection between liver cells and blood, perhaps leading to cirrhosis. Heart Failure and Atherosclerosis: Some forms involve excess collagen deposition, which can stiffen the heart or block blood flow © McGraw Hill, LLC 25  Major Cell Types of Connective Tissue Fibroblasts: Most common fixed cell Large star-shaped cell Secrete fibers into extracellular matrix Macrophages (Histiocytes): Usually attached to fibers, but can detach and wander Conduct phagocytosis Defend against infection Mast Cells: Large cells, widely distributed Release heparin to prevent blood clotting Release histamine, which causes inflammatory response © McGraw Hill, LLC 26  Figures 5.15, 5.16, and 5.17 Fibroblasts, Macrophages, and Mast Cells Juergen Berger/Science Source Biology Pics/Science Source Steve Gschmeissner/Science Source © McGraw Hill, LLC 27  Connective Tissue Fibers Fibroblasts produce 3 types of fibers in connective tissue: Collagen Fibers: Thick threads of collagen, the body’s main structural protein Great tensile strength and flexible, slightly elastic Found in ligaments and tendons Elastic (Yellow) Fibers: Composed of elastin protein; branching Can stretch and return to original shape Not as strong as collagen fibers Found in vocal cords, respiratory air passages Reticular Fibers: Thin, branching fibers of collagen Form delicate, supporting networks Found in spleen, liver © McGraw Hill, LLC 28  Figure 5.18 Collagen and Elastic Fibers Prof. P.M. Motta/Univ. “La Sapienza,” Rome/Science Source © McGraw Hill, LLC 29  Table 5.6 Components of Connective Tissue Component Characteristics Function Cellular Fibroblasts Widely distributed, large, star-shaped Secrete proteins that become cells fibers Macrophages Motile cells sometimes attached to Clear foreign particles from fibers tissues by phagocytosis Mast cells Large cells, usually located near Release substances that may blood vessels help prevent blood clotting (heparin) and promote inflammation (histamine) Extracellular Matrix Collagen fibers (white Thick, threadlike fibers of collagen Hold structures together fibers) with great tensile strength Elastic fibers (yellow Bundles of microfibrils embedded in Provide elastic quality to parts fibers) elastin that stretch Reticular fibers Thin fibers of collagen Form delicate supportive networks within tissues Ground substance Nonfibrous protein and other Fills in spaces around cells and molecules, and varying amounts of fibers fluid © McGraw Hill, LLC 30  Categories of Connective Tissue Connective tissues can be classified in 2 major categories: Connective Tissue Proper: Loose connective tissues: Fewer collagen fibers than dense tissues Types: Areolar, Adipose, Reticular Dense connective tissues: Contain abundant collagen fibers Types: Dense regular, Dense irregular, Elastic Specialized connective tissues: Cartilage Bone Blood © McGraw Hill, LLC 31  Clinical Application 5.2 Abnormalities of Collagen Collagen makes up >60% of the protein in bone and cartilage, and a large percentage of dry weight of skin, tendons, ligaments Has a very precise structure, and is vulnerable to disruption Examples: Chondrodysplasia: Collagen chains are asymmetric and too wide, causing stunted growth and deformed joints Marfan syndrome: Deficiency of the protein fibrillin; leads to long limbs, spindly fingers, sunken chest, weak aorta, dislocation of the lens of the eye © McGraw Hill, LLC 32  Areolar Connective and Adipose Tissues Areolar connective tissue: Forms thin, delicate membranes Cells are mainly fibroblasts, in a gel-like ground substance Collagenous and elastic fibers In subcutaneous layer Beneath most epithelia, where it nourishes nearby epithelial cells Adipose tissue (fat): Adipocytes store fat Push their nuclei to one side Crowd out other cell types Cushions and insulates Beneath skin (subcutaneous layer), behind eyeballs, around heart and kidneys, in spaces between muscles © McGraw Hill, LLC 33  Figures 5.19 and 5.20 Areolar Connective and Adipose Tissues Both (b): Alvin Telser/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 34  Reticular and Dense Regular Connective Tissues Reticular Connective Tissue: Composed of network of thin reticular fibers Supports walls of internal organs Walls of liver, spleen Dense Regular Connective Tissue: Closely packed collagenous fibers Fine network of elastic fibers Most cells are fibroblasts Very strong, withstands pulling Binds body parts together Tendons, ligaments, dermis Poor blood supply; slow to heal © McGraw Hill, LLC 35  Figures 5.21 and 5.22 Reticular and Dense Regular Connective Tissues (b): Al Telser/McGraw Hill (b): Dennis Strete/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 36  Dense Irregular and Elastic Connective Tissues Dense Irregular Connective Tissue: Randomly organized, thick, interwoven collagenous fibers Can withstand tension exerted from different directions Dermis of skin Around skeletal muscles Elastic Connective Tissue: Abundant yellow elastic fibers, and some collagenous fibers Fibroblasts Attachments between bones of spinal column Walls of hollow organs, such as large arteries, airways Parts of heart Elastic quality, stretches © McGraw Hill, LLC 37  Figures 5.23 and 5.24 Dense Irregular and Elastic Connective Tissues (b): Victor P. Eroschenko (b): Al Telser/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 38  Specialized Connective Tissues Specialized Connective Tissues: Cartilage, bone and blood Each contains a unique matrix with specialized cells Cartilage: A rigid, specialized connective tissue Support, framework, attachments Protection of underlying tissue Models for developing bone Matrix contains collagen in gel-like ground substance Chondrocytes (cartilage cells) in lacunae (chambers), surrounded by matrix Lacks blood supply; heals slowly Covered by perichondrium (connective tissue), which provides some nutrients to the cartilage 3 types of cartilage: Hyaline, Elastic, and Fibrocartilage © McGraw Hill, LLC 39  Specialized Connective Tissues: Cartilage Hyaline cartilage: Most common type Fine collagen fibers in matrix Ends of bones in joints, nose, respiratory passages, embryonic skeleton Elastic cartilage: Flexible, due to elastic fibers in matrix External ear, larynx Fibrocartilage: Very tough, due to many collagen fibers Shock absorber Intervertebral discs, pads (menisci) of knee, and pelvic girdle © McGraw Hill, LLC 40  Figures 5.25 and 5.26 Hyaline and Elastic Cartilage Both (b): Al Telser/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 41  Figure 5.27 Fibrocartilage (b): Victor P. Eroschenko Access the text alternative for slide images. © McGraw Hill, LLC 42  Specialized Connective Tissues: Bone Bone (Osseous Tissue): Most rigid connective tissue Solid matrix, composed of mineral (Ca) salts and collagen Supports structures Protects vital structures Produces blood cells Stores and releases Ca and P Attachment sites for muscles Forms skeleton Contain osteocytes (bone cells) in lacunae 2 types: compact and spongy © McGraw Hill, LLC 43  Types of Bone Tissue: Compact and Spongy Bone Compact Bone: Osteoblasts deposit matrix in lamellae (layers) Lamellae occur in rings around central canals Osteocytes + matrix + central canal form cylindrical units called osteons Osteocytes send out processes into canaliculi, and share blood supply Osteons: Osteons are cemented together to form compact bone Central canals contain blood vessels; bone is well-nourished, heals more quickly than cartilage Spongy Bone: Makes up interior part of bone Consists of bony plates containing osteocytes, with space between them for marrow Lighter in weight than compact bone © McGraw Hill, LLC 44  Figure 5.28 Compact Bone and Osteocyte (b): Dennis Strete/McGraw Hill; (c): Prof. P. Motta/Univ. “La Sapienza,” Rome/Science Source Access the text alternative for slide images. © McGraw Hill, LLC 45  Specialized Connective Tissues: Blood Blood: Formed elements (cells and fragments) suspended in fluid matrix called plasma Types of formed elements: Red blood cells transport gases White blood cells defend again infection Platelets help in blood clotting Transports substances around body © McGraw Hill, LLC 46  Figure 5.29 Blood (b): Alvin Telser/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 47  Table 5.7 Connective Tissues Type Description Function Location Connective Tissue Proper Areolar connective Cells in fluid-gel matrix Binds organs Beneath the skin, between muscles, beneath epithelial tissue tissues Adipose tissue Cells in fluid-gel matrix Protects, insulates, stores fat Beneath the skin, around the kidneys, behind the eyeballs, on the surface of the heart Reticular connective Cells in fluid-gel matrix Supports Walls of liver and spleen tissue Dense regular Cells in fluid-gel matrix Binds body parts Tendons, ligaments connective tissue Dense irregular Cells in fluid-gel matrix Sustains tissue tension In the deep layer of skin connective tissue Elastic connective Cells in fluid-gel matrix Provides elastic quality Connecting parts of the spinal column, in walls of tissue arteries and airways Specialized Connective Tissue Hyaline cartilage Cells in solid-gel matrix Supports, protects, provides Ends of bones, nose, and rings in walls of respiratory framework passages Elastic cartilage Cells in solid-gel matrix Supports, protects, provides Framework of external ear and part of larynx flexible framework Fibrocartilage Cells in solid-gel matrix Supports, protects, absorbs shock Between bony parts of spinal column, parts of pelvic girdle, and knee Bone Cells in solid matrix Supports, protects, provides Bones of skeleton, middle ear framework Blood Cells and platelets in Transports gases, defends against Throughout the body in a closed system of blood fluid matrix disease, clotting vessels and heart chambers © McGraw Hill, LLC 48  5.4 Membranes Membranes are sheets of cells. Epithelial membranes are composed of epithelial and connective tissue; cover body surfaces and line cavities. 3 types of epithelial membranes: Serous membranes: Line body cavities that do not open to outside of body Inner linings of thorax and abdomen; covers organs Simple squamous epithelium + areolar connective tissue Secrete serous fluid for lubrication, reducing friction Mucous membranes: Line cavities and tubes that open to the outside of body Lining of digestive, respiratory, urinary, and reproductive tracts Epithelium + areolar connective tissue Goblet cells secrete mucus © McGraw Hill, LLC 49  Types of Membranes Cutaneous membranes: Covers body surface Commonly called skin Part of integumentary system Synovial membranes: Different from epithelial membranes Composed entirely of connective tissue Line joint cavities © McGraw Hill, LLC 50  5.5 Muscle Tissues General Characteristics: Excitable; respond to nervous stimulation Muscle cells are also called muscle fibers Contractile; can shorten and thicken 3 types of muscle tissue: skeletal, cardiac, and smooth Skeletal muscle tissue: Attached to bones Striated Voluntary Long, cylindrical, multinucleated cells Stimulated by nerve cells © McGraw Hill, LLC 51  Figure 5.30 Skeletal Muscle Tissue (b): Alvin Telser/ McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 52  Smooth and Cardiac Muscle Tissues Smooth muscle tissue: Non-striated Spindle-shaped fibers Walls of hollow organs and blood vessels Involuntary Cardiac muscle tissue: Only in wall of heart Branching cells Involuntary Striated Intercalated discs (specialized intercellular junctions) © McGraw Hill, LLC 53  Figures 5.31 and 5.32 Smooth and Cardiac Muscle Tissues Both (b): Al Telser/McGraw Hill Access the text alternative for slide images. © McGraw Hill, LLC 54  5.6 Nervous Tissue Nervous tissues: Found in brain, spinal cord, peripheral nerves Neurons: Main cells, which are specialized for communication, via conduction of nerve impulses (sensory reception, motor control) Coordinate, integrate, and regulate body functions Composed of cell body (soma), dendrites, and an axon Neuroglia: Cells that support and nourish neurons © McGraw Hill, LLC 55  Figure 5.33 Nervous Tissue and Neuron Structure (b): Ed Reschke Access the text alternative for slide images. © McGraw Hill, LLC 56  5.2 From Science to Technology Tissue Engineering: Building a Replacement Bladder Donor organs are in short supply Tissue Engineering is showing promise for organ replacement, by growing cells or extracellular matrix from a person’s own cells or matrix, on a synthetic scaffold. No rejection by immune system Has already been used to provide skin, cartilage, bone, blood vessels Urinary bladders are being replaced by growing tissue donated by the patient Patient’s bladder tissue contains progenitor cells for smooth muscle and uroepithelium, which are used to grow a new bladder on a synthetic dome After implant, synthetic scaffold degenerates over time, leaving new bladder in place © McGraw Hill, LLC 57  Table 5.8 Excitable Tissues: Muscle and Nervous Tissues Type Description Function Location Skeletal muscle Long, thread-like cells, Voluntary movements Muscles usually tissue striated, many nuclei of skeletal parts attached to bones Smooth muscle Shorter cells, single, Involuntary Walls of hollow tissue central nucleus movements of internal internal organs organs Cardiac muscle Branched cells, Heart movements Heart muscle tissue striated, single nucleus Nervous tissue Cells with cytoplasmic Sensory reception, Brain, spinal cord, extensions release of and peripheral neurotransmitter, and nerves conduction of electrical impulses © McGraw Hill, LLC 58  End of Main Content Because learning changes everything. ® www.mheducation.com © McGraw Hill LLC. 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