Week 3,4 The tissue level of organization new.pdf

Because learning changes everything.® Chapter 04 Tissues Seeley’s ANATOMY & PHYSIOLOGY Thirteenth Edition Cinnamon VanPutte, Jennifer Regan, Andrew Russo © 2023 McGraw Hill, LLC. All rights reserved...

Because learning changes everything.® Chapter 04 Tissues Seeley’s ANATOMY & PHYSIOLOGY Thirteenth Edition Cinnamon VanPutte, Jennifer Regan, Andrew Russo © 2023 McGraw Hill, LLC. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw Hill, LLC.  Learning Outcome 2 Describe the structure and function of different tissue types of organization. Epithelial tissue. Connective tissue. Muscle tissue. Nerve tissue. Tissue repair and tissue aging. © McGraw Hill, LLC 2 4.1 Tissues and Histology Tissue is a collection of similar cells and surrounding substances. Tissue classification based on structure of cells, composition of noncellular extracellular matrix, and cell function. Four primary tissue types: Epithelial. Connective. Muscle. Nervous. Histology: microscopic study of tissues. Biopsy: removal of tissues for diagnostic purposes. Autopsy: examination of organs of a dead body to determine cause of death. © McGraw Hill, LLC 3  4.3 Epithelial Tissue Characteristics of epithelial tissue: Mostly composed of cells; very little extracellular matrix Covers body surfaces and forms glands. Outside surface of the body. Lining of digestive, respiratory and urogenital systems. Heart and blood vessels. Linings of many body cavities. Has distinct tissue surfaces. Free (apical), basal, and lateral surfaces. Basement membrane – connects the basal layer to underlying tissue Cells connect to surrounding cells and extracellular matrix. Avascular – materials must move by diffusion from underlying connective tissue High regeneration capacity. © McGraw Hill, LLC 4  Basement Membrane Consists of two layers – basal lamina and reticular lamina Basal lamina consists of lamina lucida and lamina densa Made of specialized extracellular material secreted by the epithelial cells – collagen, glycoproteins (laminin and fibronectin), and proteoglycans. Supports and guides cells migration during tissue repair; porous to allow movement of materials to and from the epithelial cells above © McGraw Hill, LLC 5  Characteristics of Epithelial Tissue CHX: tightly packed cells. Access the text alternative for slide images. © McGraw Hill, LLC 6  Functions of Epithelial Tissues Protecting underlying structures; For example, epithelium lining the mouth. Acting as a barrier; For example, skin. Permitting the passage of substances; For example, nephrons in kidney. Secreting substances; For example, mucous glands. Absorbing substances; For example, lining of small intestine. © McGraw Hill, LLC 7  Classification of Epithelial Tissues 1 Classifications based on number of cell layers. Simple- one layer of cells. Each extends from basement membrane to the free surface. Stratified- more than one (multiple layer of cells ). Shape of cells of the apical layer used to name the tissue. Pseudostratified columnar- tissue appears to be stratified, but all cells contact basement membrane, so it is in fact simple. Transitional- special type of stratified epithelium where the cell shape changes from cuboidal/columnar to squamous-like when stretched. Classifications based on cell shape. Squamous- flat, scalelike. Cuboidal- about equal in height and width. Columnar- taller than wide. © McGraw Hill, LLC 8  Classification of Epithelial Tissues 2 Access the text alternative for slide images. © McGraw Hill, LLC 9  Simple Epithelium TABLE 4.2 Simple Epithelium (a) Simple Squamous Kidney Epithelium (b) Simple Cuboidal Kidney Epithelium (c) Simple Columnar Epithelium (d) Pseudostratified Columnar Epithelium © McGraw Hill, LLC 10  Stratified Squamous Epithelium TABLE 4.3 Stratified Epithelium (a) Stratified Squamous Epithelium The stratified squamous epithelium is multiple layers of cells that are cube-shaped in the basal layer and progressively flattened toward the surface. (c) Stratified Columnar Epithelium The stratified columnar epithelium is multiple layers of cells with tall, thin cells resting on layers of more cube-shaped cells. Al Telser/McGraw Hill © McGraw Hill, LLC 11  Transitional Epithelium TABLE 4.3 Stratified Epithelium (d) Transitional Epithelium The transitional epithelium is stratified cells that appear cube-shaped when the organ or tube is not stretched and squamous when stretched. (urinary bladder) Victor P. Eroschenko © McGraw Hill, LLC 12  Glands Specialized secretory organs of epithelium with supporting network of C.T. Two types of glands formed by infoldings of epithelium: Endocrine: no open contact with exterior; no ducts; have an extensive network of blood vessels; produce hormones. The secretions of endocrine glands are released directly into the bloodstream. Exocrine: open contact maintained with exterior by way ducts that open onto the free surface of the epithelium. © McGraw Hill, LLC 13  Gland Classification by Structure 1 Unicellular glands: single cell, For example, goblet cells that secrete mucus. © McGraw Hill, LLC 14  Gland Classification by Structure 2 Simple glands Multicellular glands with a single, nonbranched duct. Secretory portion can be tubular or acinar (sac-like) Includes simple tubular, simple branched tubular, simple acinar, and simple branched acinar Access the text alternative for slide images. © McGraw Hill, LLC 15  Gland Classification by Structure 3 Compound glands: Multicellular glands with ducts with many branches. Includes: compound tubular: A gland with branching ducts that end in tubular. compound acinar: A gland with branching ducts that end in acini compound tubulo-acinar: Secretory portion both tubular, and acinar Access the text alternative for slide images. © McGraw Hill, LLC 16  Modes of Exocrine Gland Secretion Merocrine – exocytosis (most common type). Apocrine – discharges fragments of the gland's cells during secretion; mammary glands. Holocrine – shedding of entire cells; sebaceous glands. Access the text alternative for slide images. © McGraw Hill, LLC 17  4.4 Connective Tissue Abundant; found in every organ. Consists of cells separated by extracellular matrix. consists of cells with much extracellular material (matrix) between them. Many diverse types and functions. © McGraw Hill, LLC 18  Functions of Connective Tissue Enclose organs and separate organs into layers. Connect tissues to one another; for example, tendons and ligaments. Support and movement; for example, bones. Storage; for example, fat. Cushion and insulate; for example, fat. Transport; for example, blood. Protect; for example, cells of immune system. © McGraw Hill, LLC 19  Cells of Connective Tissue 1 Specialized cells produce the extracellular matrix. Descriptive word stems. Blasts: create the matrix. Cytes: maintain the matrix. Clasts: break the matrix down for remodeling. © McGraw Hill, LLC 20  Cells of Connective Tissue 2 C.T. cells that form the structural framework of the body include bone cells, cartilage cells, and fibrous tissue cells. Osteoblasts form bone, osteocytes maintain bone, and osteoclasts break it down. Chondroblasts form cartilage and chondrocytes maintain cartilage. Fibroblasts form fibrous connective tissue and fibrocytes maintain fibrous connective tissue. © McGraw Hill, LLC 21  Cells of Connective Tissue 3 Adipose or fat cells (adipocytes). contains large amounts of lipids. - Common in some tissues (dermis of skin); rare in some (cartilage). Mast cells. Common beneath membranes and along small blood vessels. Important role in inflammation; can release heparin, histamine, and proteolytic enzymes in response to injury. White blood cells (leukocytes). Respond to injury or infection. Macrophages. Phagocytize to provide protection against foreign and injured cells. Platelets. Fragments of hematopoietic cells involved in clotting. Undifferentiated mesenchyme (mezənˌkīm) (stem cells). Have potential to differentiate into adult cell types. © McGraw Hill, LLC 22  Extracellular Matrix Three major components to the extracellular matrix: protein fibers, ground substance, fluid. - Protein fibers of the matrix: Collagen. Most common protein in body; strong, flexible, inelastic. Reticular. Fill spaces between tissues and organs. Fine collagenous, form branching networks. Elastin. Returns to its original shape after distension or compression. Contains molecules of protein elastin that resemble coiled springs; molecules are cross-linked. © McGraw Hill, LLC 23  Molecules of the Connective Tissue Matrix Access the text alternative for slide images. © McGraw Hill, LLC 24  Classification of Connective Tissue Connective Tissue Proper. Loose – fewer fibers, more ground substance; areolar, adipose, reticular Dense – more fibers, less ground substance; dense regular and irregular collagenous, dense regular and irregular elastic Supporting CT. Cartilage – semisolid matrix; hyaline, fibrocartilage, elastic Bone – solid matrix; spongy and compact Fluid CT. (fluid matrix) Blood. Hematopoietic tissue; red and yellow bone marrow © McGraw Hill, LLC 25  CT Proper: Loose CT Areolar Connective Tissue TABLE 4.8 Connective Tissue Proper: Loose Connective Tissue (a) Areolar Connective Tissue Areolar connective tissue contains cells such as fibroblasts, macrophages, and lymphocytes that are immersed in a fine network of collagen fibers. Ed Reschke © McGraw Hill, LLC 26  CT Proper: Loose CT Adipose Tissue Yellow adipose tissue is white at birth but turns yellow with age. Brown adipose gets its color from cytochromes and is specialized to generate heat. TABLE 4.8 Connective Tissue Proper: Loose Connective Tissue (b) Adipose Tissue Adipose tissue contains cells, termed adipose cells, that store (Lipids)triglycerides; these cells are surrounded by a very sparse extracellular matrix. Ed Reschke © McGraw Hill, LLC 27  CT Proper: Loose CT Reticular Tissue TABLE 4.8 Connective Tissue Proper: Loose Connective Tissue (c) Reticular Tissue Reticular tissue is composed of a fine network of reticular fiber irregularly arranged. Al Telser/McGraw Hill © McGraw Hill, LLC 28  Dense Connective Tissue Dense Regular and Irregular Collagenous CT TABLE 4.9 Connective Tissue Proper: Dense Connective Tissue (a) Dense Regular Collagenous Connective Tissue Dense regular collagenous connective tissue is composed of a matrix of collagen fibers running somewhat in the same direction. (Tendons) (Left image): Victor P. Eroschenko; (Right image): Ed Reschke/Stone/Getty Images (c) Dense Irregular Collagenous Connective Tissue Dense irregular collagenous connective tissue is composed of fibers going in all directions or on alternating planes aligned in a similar direction. Dermis of skin (Left image): Victor P. Eroschenko; (Right image): Ed Reschke/Peter Arnold, Inc./Getty Images © McGraw Hill, LLC 29  Dense Connective Tissue Dense Regular and Irregular Elastic CT TABLE 4.9 Connective Tissue Proper: Dense Connective Tissue (b) Dense Regular Elastic Connective Tissue Dense regular elastic connective tissue is composed of regularly arranged collagen fibers and elastic fibers. (Vocal Cord) Victor P. Eroschenko (d) Dense Irregular Elastic Connective Tissue Dense irregular collagenous connective tissue is composed of fibers going in all directions or on alternating planes aligned in a similar direction. ( Dermis of Skin) Ed Reschke © McGraw Hill, LLC 30  Supporting Connective Tissue: Cartilage Composed of chondrocytes located in matrix-surrounded spaces called lacunae. Type of cartilage determined by components of the matrix. Firm consistency. Ground substance: Proteoglycans and hyaluronic acid complexed together trap large amounts of water. Tissue can spring back after being compressed. Avascular and no nerve supply. Heals slowly. Perichondrium. Dense irregular connective tissue that surrounds cartilage. Fibroblasts of perichondrium can differentiate into chondroblasts. Types of cartilage. Hyaline. Fibrocartilage. Elastic. © McGraw Hill, LLC 31  Supporting Connective Tissue Hyaline Cartilage TABLE 4.10 Supporting Connective Tissue: Cartilage (a) Hyaline Cartilage Hyaline cartilage is composed of chondrocyte cells located in spaces, termed lacunae; the matrix is firm but flexible and contains collagen fibers. Victor P. Eroschenko © McGraw Hill, LLC 32  Supporting Connective Tissue Fibrocartilage TABLE 4.10 Supporting Connective Tissue: Cartilage (b) Fibrocartilage Fibrocartilage is composed of collagen fibers similar to those in hyaline cartilage, but they are more numerous and are arranged in thick bundles. Intervertebral discs exhibit a great deal of strength because of the presence of thick bundles of collagen. Victor P. Eroschenko © McGraw Hill, LLC 33  Supporting Connective Tissue Elastic Cartilage TABLE 4.10 Supporting Connective Tissue: Cartilage (c) Elastic Cartilage Elastic cartilage is similar to hyaline cartilage, but the matrix also contains elastic fibers. (external ears) Victor P. Eroschenko © McGraw Hill, LLC 34  Supporting Connective Tissue: Bone Hard connective tissue composed of living cells (osteocytes) and mineralized matrix. Matrix: gives strength and rigidity; allows bone to support and protect other tissues and organs. Organic: collagen fibers. Inorganic: hydroxyapatite (calcium and phosphate). Osteocytes located in lacunae with a rich blood supply. Types. Spongy bone. Compact bone. © McGraw Hill, LLC 35  Supporting Connective Tissue Bone TABLE 4.11 Supporting Connective Tissue: Bone (a) Spongy Bone A micrograph and an illustration show spongy bone that contains bone trabecula with matrix, osteoblast nuclei, and osteocyte nucleus in the bone marrow. Victor P. Eroschenko (b) Dense Irregular Elastic Connective Tissue Compact bone is composed of predominantly a hard bony matrix with bone cells located in lacunae. Trent Stephens © McGraw Hill, LLC 36  Fluid Connective Tissue: Blood Fluid matrix and lacks fibers. Matrix formed by other tissues, unlike other types of connective tissue. Moves through vessels, but both fluid and cells can move in/out of the vessels. Formed elements: red cells, white cells, and platelets. TABLE 4.12 Fluid Connective Tissue: Blood and Hematopoietic Tissue (a) Blood Blood, a connective tissue, is composed of blood cells and a fluid matrix. Ed Reschke/Stone/Getty Images © McGraw Hill, LLC 37  Fluid Connective Tissue: Hematopoietic Tissue Forms blood cells. Found in bone marrow. Types of bone marrow. Red: hematopoietic tissue surrounded by a framework of reticular fibers. Produces red and white blood cells. Yellow: yellow adipose tissue; does not produce blood cells. As children grow, yellow marrow replaces much of red marrow. TABLE 4.12 Fluid Connective Tissue: Blood and Hematopoietic Tissue (b) Bone Marrow Bone marrow is composed of a reticular fiber network containing numerous blood-forming cells. Ed Reschke © McGraw Hill, LLC 38  4.5 Muscle Tissue Characteristics of Muscle Tissue: Contracts (contractility) or shortens with force. Moves body and pumps blood. Types. Skeletal: most attached to skeleton (bones), but some attached to other types of connective tissue; striated and voluntary. Cardiac: muscle of the heart; striated and involuntary. Smooth: muscle associated with tubular structures and with the skin; nonstriated and involuntary. © McGraw Hill, LLC 39  TABLE 4.14 Muscle Tissue (a) Skeletal Muscle Structure: Skeletal muscle cells or fibers appear striated (banded); cells are large, Skeletal muscle. long, and cylindrical, with many nuclei Skeletal muscle cells, also termed fibers, are long and cylindrical with many nuclei located at Function: the cell periphery. Under the microscope, the Movement of the body; under voluntary control cells appear banded. Location: Attached to bone or other connective tissue (b) Cardiac Muscle Structure: Cardiac muscle cells are cylindrical and striated and have a single The illustration of the cardiac muscle shows long nucleus; they are branched and connected to one another by cardiac muscles fibers interconnected to one intercalated disks, which contain gap junctions another. The muscle cells have a nucleus and striations. Intercalated disks are special junctions Function: between cells. The micrograph shows the nucleus Pumps the blood; under involuntary (unconscious) control as dense matter in theEdmiddle Reschkeof the long muscle fiber cells. Location: In the heart (c) Smooth Muscle Structure: Smooth muscle cells are tapered at each end, are not striated, and have a single nucleus Function: Smooth muscle cells are tapered at each end, Regulates the size of organs, forces fluid through tubes, controls the are not striated, and have a single nucleus. amount of light entering the eye, and produces “goose bumps” in the skin; under involuntary (unconscious) control Location: © McGraw Hill, LLC In hollow organs, such as the stomach and intestine; skin and eyes 40  4.6 Nervous Tissue Neurons (nerve cells) have the ability to produce electrical signals called action potentials. Parts: Cell body: contains nucleus. Axon: cell process; conducts impulses away from cell body; usually only one per neuron. Dendrites: cell processes; receive impulses from other neurons; conducts impulses toward cell body can be many per neuron. Types: Multipolar, bipolar, and pseudo-unipolar. - Glia are support cells of the brain, spinal cord and nerves. Nourish, protect, and insulate neurons. © McGraw Hill, LLC 41  Multipolar Neuron Structure: A neuron consists of dendrites, a cell body, and a long axon; glia, or support cells, surround the neurons Function: Neurons transmit information in the form of action potentials, store information, and integrate and evaluate data; glia support, protect, and form specialized sheaths around axons Location: In the brain, spinal cord, and ganglia © McGraw Hill, LLC 42  Pseudo-Unipolar Neuron TABLE 4.15 Types of Neurons (b) Pseudo-unipolar Neuron Structure: The neuron consists of a cell body with one axon Function: A pseudo unipolar neuron is a cell that consists of a cell body with one axon. Conducts action potentials from the periphery to the brain or spinal cord Location: Trent Stephens In ganglia outside the brain and spinal cord © McGraw Hill, LLC 43  4.7 Tissue Membranes Thin sheet of tissue that covers a structure or lines a cavity. Consist of superficial epithelial tissue and underlying connective tissue. Cutaneous (skin – Chap. 5), mucous, serous, and synovial. Mucous. Line cavities that open to the outside of body. Secrete mucus. Contains epithelium with goblet cells, basement membrane, lamina propria (sometimes with smooth muscle). Found in respiratory, digestive, urinary and reproductive systems. Serous. Simple squamous epithelium called mesothelium, basement membrane, thin layer of loose C.T. Line cavities not open to exterior (protects internal organs from friction) Pericardial, pleural, peritoneal. Synovial. Lines joint cavities. Produce fluid rich in hyaluronic acid. © McGraw Hill, LLC 44  4.9 Tissue Repair Substitution of viable cells for dead cells by regeneration or replacement. Regeneration: new cells of same type are produced; function is restored. Replacement: new type of tissue develops, resulting in scar and loss of some function. Classification of cells based on ability to regenerate. Labile: capable of mitosis through life; skin, mucous membranes, hematopoietic tissue, lymphatic tissue. Stable: no mitosis after growth ends, but can divide after injury; liver, pancreas, endocrine cells. Permanent: if killed, replaced by a different type of cell; limited regenerative ability; nervous, skeletal and cardiac muscle. © McGraw Hill, LLC 45  Skin Repair 1 Example of tissue repair; refer to Process Figure on the next slide 1. Primary union: edges of wound are close together (a part) Wound fills with blood. Clot forms: fibrin threads start to contract; pull edges together. Scab. Inflammatory response; pus forms as white cells die. Granulation tissue. Replaces clot, delicate C.T. composed of fibroblasts, collagen fibers, capillaries. Scar. Formed from granulation tissue. Tissue turns from red to white as capillaries are forced out. 2. Secondary union: edges of wound are not closed (far a part); greater chance of infection. Clot may not close gap. Inflammatory response greater. Wound contraction occurs leading to greater scarring. © McGraw Hill, LLC 46  Molecular Tissue Profiles of Cancer Tissue The most common types of cancer are from epithelial tissue with its more rapid cell division. Carcinomas – cancers of epithelial tissue; include nearly all lung, breast, colon, prostate, and skin cancers. Adenocarcinomas – derived from glandular epithelium. Sarcomas – relatively rare cancers of mesodermal tissue (connective and muscular) © McGraw Hill, LLC 47  Effects of Aging on Tissues - Cells divide more slowly. - Rate of blood cell synthesis declines in the elderly. - Injuries don’t heal as readily. - Collagen fibers become more irregular in structure, though they may increase in number: tendons and ligaments become less flexible and more fragile. - Elastic fibers become less elastic. Changes in collagen and elastin result in. Arterial walls and elastic ligaments become less elastic. Atherosclerosis and reduced blood supply to tissues. Wrinkling of the skin. Increased tendency for bones to break. © McGraw Hill, LLC 48 Because learning changes everything. ® www.mheducation.com © 2023 McGraw Hill, LLC. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw Hill, LLC.