Chapter 5 Lecture.pptx

Because learning changes everything. Chapter 05 Copyright 2022 © 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 o...

Because learning changes everything. Chapter 05 Copyright 2022 © 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 2 Figure 5.1 Intercellular Junctions Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 3 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) Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 4 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 5 Figures 5.3 and 5.4 Simple Squamous and Simple Cuboidal Epithelia (b): Al Telser/McGraw-Hill Education; (c): Ed Reschke; (b): Victor P. Eroschenko Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 6 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 7 Figures 5.5 and 5.7 Simple Columnar and Pseudostratified Columnar Epithelia (b): Victor P. Eroschenko; (b): Dennis Strete/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 8 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 9 Figures 5.8 and 5.9 Stratified Squamous and Stratified Cuboidal Epithelia (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 10 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 11 Figures 5.10 and 5.11 Stratified Columnar and Transitional Epithelia (b): Al Telser/McGraw-Hill Education; (b, d): Ed Reschke Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 12 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 13 Features of Exocrine Glands 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 14 Figure 5.13 Exocrine Glandular Secretions Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 15 5.3 Connective Tissues 1 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 16 5.3 Connective Tissues 2 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 17 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 18 Figures 5.15, 5.16, and 5.17 Fibroblasts, Macrophages, and Mast Cells (L): Juergen Berger/Science Source; (M): Biology Pics/Science Source; (R): Steve Gschmeissner/Science Source Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 19 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 20 Figure 5.18 Collagen and Elastic Fibers Prof. P.M. Motta/ Univ. “La Sapienza,” Rome/Science Source Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 21 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 22 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 23 Figures 5.19 and 5.20 Areolar Connective and Adipose Tissues (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 24 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 25 Figures 5.21 and 5.22 Reticular and Dense Regular Connective Tissues (b): Al Telser/McGraw-Hill Education; (b): Dennis Strete/McGraw-Hill Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 26 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 27 Figures 5.23 and 5.24 Dense Irregular and Elastic Connective Tissues (b): ©Victor P. Eroschenko; (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 28 Specialized Connective Tissues Specialized Connective Tissues: Cartilage, bone and blood Have 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 3 types of cartilage: Hyaline, Elastic, and Fibrocartilage Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 29 Three Types of 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 30 Figures 5.25 and 5.26 Hyaline and Elastic Cartilage (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 31 Figure 5.27 Fibrocartilage (b): Victor P. Eroschenko Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 32 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, P Attachment sites for muscles Forms skeleton Contain osteocytes (bone cells) in lacunae 2 types: compact and spongy Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 33 Bone Tissue 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 34 Figure 5.28 Compact Bone and Osteocyte (b): Dennis Strete/McGraw-Hill Education; (c): P.M. Motta/Univ. “La Sapienza,” Rome/Science Source Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 35 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 36 Figure 5.29 Blood (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 37 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 38 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 39 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 40 Figure 5.30 Skeletal Muscle Tissue (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 41 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 42 Figures 5.31 and 5.32 Smooth and Cardiac Muscle Tissues (b): Al Telser/McGraw-Hill Education Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 43 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 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 44 Figure 5.33 Nervous Tissue (b): Ed Reschke Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 45