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Audio Chapter Summaries
Copyright © 2025 by Elsevier Inc. All rights reserved, including those for text and data mining, AI training, and similar technologies.
Copyright © 2025 by Elsevier Inc. All rights reserved, including those for text and data mining, AI training, and similar technologies.
Patton: Structure & Function of the Body, 17th Edition
Chapter 04: Tissues
Audio Chapter Summaries
Welcome to the audio review of Chapter 4: Tissues.
There are four main tissue types:
Epithelial tissue forms sheets that cover or line the body;
Connective tissue provides structural and functional support;
Muscle tissue contracts to produce movement; and
Nervous tissue, which senses, conducts, and processes information.
The extracellular matrix (or ECM), also called simply “matrix” is the internal fluid environment of the body, surrounding cells of each tissue. The ECM is mostly water, but also often contains fibers and other substances that give it thick, jellylike consistency. Two fibers within the matrix are collagen, the protein that forms twisted ropelike fibers that provide flexible strength to tissue; and elastin, a rubbery protein that provides elastic stretch and rebound in tissues. In addition, matrix includes polysaccharides and proteoglycans that help link cells, absorb shock, regulate function, and provide lubrication.
Next, we’ll review each of the four main types of tissue in more detail.
Epithelial tissue covers the body and lines body cavities.
The cells of epithelial tissue are packed closely together with little matrix.
Epithelial tissue is classified by the shape of the cells that form it.
Squamous epithelial tissue has flat and scalelike cells.
Cuboidal epithelial tissue has cube-shaped cells.
Columnar epithelial tissue has cells that are higher than they are wide.
Transitional epithelial tissue has cells of varying shapes that can stretch.
Epithelial tissue is also classified by the arrangement of cells into one or more layers: simple (one layer) or stratified (more than one layer).
Squamous epithelium is either simple or stratified.
Simple squamous epithelium has a single layer of scalelike cells adapted for transport (e.g., for absorption).
Stratified squamous epithelium has several layers of closely packed cells specializing in protection.
Cuboidal epithelium is also either simple or stratified.
Simple cuboidal epithelium contains a single layer of cubelike cells often specialized for secretory activity; they may secrete into ducts, directly into blood, and on the body surface.
Stratified cuboidal epithelium has two or more layers of cubelike cells, and is sometimes found in sweat glands and other locations.
Columnar epithelium is either simple or pseudostratified.
Simple columnar epithelium has tall, columnlike cells arranged in a single layer; it contains mucus-producing goblet cells; the regular columnar cells specialize in absorption.
Pseudostratified epithelium has a single layer of distorted columnar cells; note that each cell touches the basement membrane.
Transitional epithelium is also called stratified transitional epithelium. It contains up to 10 layers of roughly cuboidal cells that distort to squamous shape when stretched. Transitional epithelium is found in body areas that stretch, such as the urinary bladder.
Connective tissue is the most abundant and widely distributed tissue in the body, with many different types, appearances, and functions. It has relatively few cells in extracellular matrix between tissue cells. The five types of connective tissue are fibrous, bone, cartilage, blood, and hematopoietic tissue, and we’ll review each type next.
Fibrous connective tissue has four subtypes: loose fibrous (or areolar), adipose (or fat), reticular, and dense fibrous.
Loose fibrous or areolar connective tissue has fibrous glue (fascia) that holds organs together; collagenous and elastic fibers, plus a variety of cell types.
Adipose (or fat) tissue can be white fat, which stores lipids (such as triglycerides); or brown fat that produces heat; both types regulate metabolism.
Reticular tissue has a delicate net of collagen fibers, as in bone marrow.
Dense fibrous tissue has bundles of strong collagen fibers that are densely packed.
Regular dense fibrous tissue has parallel collagen bundles; an example is a tendon.
Irregular dense fibrous tissue has chaotic, swirling collagen bundles; an example of it is the deep layer of skin.
The next type of tissue we’ll review is bone tissue, which can be compact or cancellous.
The bone matrix is collagen bundles encrusted with calcium mineral crystals.
Compact bone is made of cylindrical osteons (haversian systems); it forms the outer walls of bones.
Cancellous bone (also called spongy bone) is made of thin, crisscrossing beams of bone; it is found inside bones.
Bone functions in support and protection.
Cartilage tissue is different than bone tissue. Cartilage tissue’s matrix is the consistency of gristlelike gel. Cartilage tissue cells are called chondrocytes.
There are three types of cartilage tissue: hyaline, fibrocartilage, and elastic.
Hyaline cartilage has a moderate amount of collagen in matrix; it forms a flexible gel.
Fibrocartilage has a matrix that is very dense with collagen; it forms a very tough, hard gel.
The matrix of elastic cartilage has some collagen with elastin; it forms a soft, elastic gel.
Blood tissue’s matrix is fluid; its functions are transportation and protection.
Hematopoietic tissue is blood-forming tissue with a liquid matrix. Now you have reviewed all the types of epithelial and connective tissue.
Next, we’ll review muscle tissue.
Muscle tissue contracts to provide movement or stability. There are three types of muscle tissue: skeletal, cardiac, and smooth.
Skeletal muscle tissue attaches to bones; it is also called
striated or
voluntary, because
control is voluntary. Striations are apparent when skeletal muscle tissue is viewed under a microscope.
Cardiac muscle tissue, also called
striated involuntary, composes the heart wall; ordinarily we cannot control cardiac contractions.
Smooth muscle tissue is also called
nonstriated (visceral) or
involuntary. It has no cross striations, and is found in blood vessels and other tube-shaped organs.
Nervous tissue is the last type of tissue we’ll review.
The function of nervous tissue is control of body functions and rapid communication between body structures.
Neurons are the conduction cells.
All neurons have a cell body and two types of processes: the axon and dendrites.
The axon carries nerve impulses away from the cell body. Think of the alliteration “axon away” to help you remember. All neurons just have one axon.
Dendrites carry nerve impulse toward the cell body. Neurons can have one or more dendrites.
Glia or neuroglia are another type of cell in nervous tissue. They are the supportive and connecting cells.
This concludes the audio review of chapter 4.
