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Tissues, Glands, and
Membranes
Chapter Five
Mrs. Hornacek
Objectives
1. Name the four main groups of tissues and give the
location and general characteristics of each.
2. Differentiate between voluntary and involuntary muscles.
3. Describe the structure of the neuron.
4. Describe the function and location of the major types of
connective tissue.
5. Describe the different structures and functions of
epithelium tissue.
6. Distinguish among the 4 major types of membranes.
7. Describe the difference between endocrine and exocrine
glands.
8. Identify tissues under a microscope and on diagrams.
Tissues
• Groups of cells that are similar in structure
and perform a common or related function
• Histology is the study of tissues
Chemical Cell Tissue Organ Organ System Whole Organism
Tissue Classification
Four main types of tissue:
Epithelial: covers surfaces, lines cavities,
and forms glands
Connective: supports
and forms the framework
of all parts of the body
Tissue Classification
Four main types of tissue:
Muscle: contracts and produces
movement
Nervous: conducts
nerve impulses
Epithelial Tissue – General
Characteristics
• Epithelium forms a protective covering for
the body
• It is the main tissue of the skin’s outer
layer
• Forms membranes, ducts, and lines body
cavities and hollow organs
Epithelial Tissue – General
Characteristics• Usually has no vascular tissue-blood
supply
– Nutrients obtained by diffusion
• Cells reproduce rapidly (rapid healing)
• Cells are tightly packed together with no
intercellular material
• Basement Membrane: Anchors epithelial
tissue to connective tissue
– Thin, non-living
Structure of Epithelial Tissue
Each epithelium is given two names:
First name indicates # cell layers present
• Simple: single cell layer
• Stratified: two or more layers
Structure of Epithelial Tissue
Second name describes the shape of its
cells
• Squamous: flattened and scale-like
• Cuboidal: boxlike, tall as they are wide
• Columnar: tall and column shaped
6 types of epithelial tissue follow
Simple Squamous
DESCRIPTION: Single layer of very thin, flattened cells
FUNCTION: Diffusion and filtration where protection is not important
LOCATION: air sacs of lungs, walls of capillaries and blood vessels, lining of heart
11
Fig05.01
(b)(a)
(d)(c)
Free surface
of tissue
Simple
squamous
epithelium
Basement
membrane
Nucleus
Free surface
of simple
squamous
epithelium
Nucleus
Connective
tissue
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©The McGraw-Hill Companies, Inc./Al Telser, photographer
©The McGraw-Hill Companies, Inc./Al Telser, photographer
Simple Cuboidal
D: single layer of cube shaped cells
F: secretion and absorption
L: lining of kidney tubules, ducts of glands,
covering surface of ovaries
13
Fig05.02
Nucleus
Basement
membrane
Free surface
of tissue
Simple
cuboidal
epithelium
Connective
tissue
Lumen
(a) (b)
©The McGraw-Hill Companies, Inc./Al Telser, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Simple Columnar
D: single layer of elongated cells, some have cilia and some may contain mucus-secreting goblet cells
F: absorption, secretion, protection, ciliated type propels substances (mucus, reproductive cells) by ciliary action
L: lining of digestive tract, uterus, gallbladder
15
Fig05.03
Nucleus
Basement
membrane
Microvilli
(free surface
of tissue)
Connective
tissue
Mucus
Cytoplasm
Goblet cell
(a) (b)©The McGraw-Hill Companies, Inc./Al Telser, photographer
Pseudostratified Columnar
D: appear “stratified” but really are a single layer with nuclei at various levels giving appearance of layered cells.
F: secretion (mostly mucus), movement of mucus by cilia
L: lining air passages like the trachea and upper respiratory tract
17
Fig05.04
(a) (b)
Cilia
(free surface
of tissue)
Goblet cell
Basement
membrane
Nucleus
Connective
tissue
Cytoplasm
©The McGraw-Hill Companies, Inc./Dennis Strete, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Stratified Squamous
D: multi-layered, dry, thick tissue. Surface
cells are flat, full of keratin and dead.
Basal cells are cuboidal or columnar.
F: protection
L: lining of esophagus, mouth, vagina,
epidermis of the skin
Fig05.05
Basement
membrane
Layer of
dividing
cells
Connective
tissue
Free surface
of tissue
Squamous
cells
(b)(a)©The McGraw-Hill Companies, Inc./Al Telser, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Transitional Epithelium
D: resembles both stratified squamous and
stratified cuboidal
F: stretches and also forms barrier to block
diffusion
L: lining of urinary bladder, ureters, urethra
21
Fig05.08
©Ed Reschke
©Ed Reschke
Stretched
transitional
epithelium
Basement
membrane
Underlying
connective tissue
Basement
membrane
Underlying
connective tissue
Unstretched
transitional
epithelium
(b)(a)
(d)(c)
Free surface
of tissue
Free surface
of tissue
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Glands
• A gland is an organ specialized to produce
a substance that is sent out to other parts
of the body, made of glandular epithelium
Glands
• Glands are divided into two categories
based on how they release secretions:
1. Exocrine: use ducts or tubes
2. Endocrine: secrete into the blood or
tissue fluid
Types of Exocrine Glands
• Merocrine
– Releases fluid product
through membrane by
exocytosis
– Salivary glands, sweat
glands in skin
Types of Exocrine Glands
• Apocrine
– Cellular product and
portions of gland cells
pinch off during
secretion
– Mammary glands
Types of Exocrine Glands
• Holocrine
– Release entire cells
filled with secretory
products
– Sebaceous glands of
the skin
Connective Tissue- General
Characteristics
• Functions: bind, support, framework, store
fat, fill spaces, produce blood cells, protect
against infection, and repair tissue
damage
• Most has a good blood supply, except
cartilage
• Composed of
scattered cells with
abundant non-living
extracellular matrix
• Extracellular matrix
contains fibers (for
support) and ground
substance (fluid,
proteins)
Connective Tissue Characteristics
Connective Tissue – Major Cell Types
• Fibroblast
– most common
– secretes fibers
– very large, star-
shaped
Connective Tissue – Major Cell Types
• Macrophage
– scavenger cells and
defend against
infection
Connective Tissue – Major Cell Types
• Mast Cells
– release heparin and
histamine
– Large
– located near blood
vessels
Connective Tissue - Fibers
• Collagenous Fiber:
strength
• Elastic Fiber:
flexibility
• Reticular Fiber:
supportive networks
5 Categories of Connective Tissue
1. Loose: areolar, adipose
2. Dense: tendons, ligaments
3. Cartilage: hyaline, elastic, fibrocartilage
4. Bone
5. Blood
1. Loose Connective Tissue
Areolar
D: gel-like matrix with fibers and different
types of cells
F: cushions organs, holds tissue fluid
L: surrounding organs, under the skin,
between muscles
35
Fig05.13
Elastic
fiber
(a) (b)
Collagenous
fiber
Fibroblast
Ground
substance
©The McGraw-Hill Companies, Inc./Dennis Strete, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Areolar Connective Tissue
Adipose
D: sparse matrix, closely packed
F: insulates, supports, protects, reserve
energy supply (fat storage)
L: under skin, around joints, padding organs
1. Loose Connective Tissue
38
Fig05.14
(a) (b)
Fat droplet
Nucleus
Cell
membrane
y.
©The McGraw-Hill Companies, Inc./Al Telser, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Adipose Connective Tissue
• Strong
• Lacks good blood supply
Dense
D: dense with collagen and elastic fibers
F: structural strength, attach muscle to bone
and bone to bone
L: vocal cords, tendons, ligaments
2. Dense Connective Tissue
41
Fig05.15
Fibroblasts
Collagenous
fibers
(a) (b)©The McGraw-Hill Companies, Inc./Dennis Strete, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Tendon. The fibers are oriented in parallel arrays. Note the
thin, dark staining nuclei of the fibroblasts. Their cytoplasm
cannot be distinguished.
Dense Regular
3. Cartilage
Hyaline Cartilage
• D: fine collagenous fibers in extracellular
matrix with chondrocytes
• F: stiff but flexible support, reduces friction
• L: nose, ends of bones, ribs, larynx,
trachea
• MOST COMMON TYPE
Fig05.16
Chondrocyte
Nucleus
Extracellular
matrix
(a) (b)
Lacuna
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Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hyaline Cartilage
Hyaline cartilage contains cells called chondrocytes embedded in a unique matrix
that gives the tissue both strength and flexibility.
3. Cartilage
Elastic Cartilage
• D: dense network of elastic fibers in
extracellular matrix with chondrocytes
• F: elasticity, support
• L: external ear, parts of larynx
Fig05.17
Chondrocyte
Elastic fibers
Nucleus
Extracellular
matrix
(a) (b)
Lacuna
©The McGraw-Hill Companies, Inc./Al Telser, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Elastic Cartilage
elastic cartilage can be distinguished by the stain for elastin that brings
out the dense bundles
3. Cartilage
Fibrocartilage Cartilage
• D: many collagenous fibers in extracellular
matrix
• F: strong, resists compression
• L: invertebral discs and joint capsules
(knees)
Fig05.18
Chondrocyte
Nucleus
Collagenous
fiber
Extracellular
matrix
(a) (b)©The McGraw-Hill Companies, Inc./Al Telser, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Fibrocartilage
Fibrocartilage from an intervertebral disk. It is distinguished by very scattered,
infrequent chondrocytes (see the tiny dark nuclei) and collagen fibers running in
the matrix.
4. Bone
Bone
• D: hard, calcified matrix with collagen
fibers, vascular, deposits of mineral salts
• F: supports, protects, stores calcium,
marrow inside is site for blood cell
formation
• L: skeletal system
54
Fig05.19
Canaliculi
Lacuna
Central
canal
Lamella
Osteon
©The McGraw-Hill Companies, Inc./Dennis Strete, photographer
(c)
©Prof. P. Motta/Univ."La Sapienza"/Photo Researchers
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
(a) (b)
Bone
Ground Bone
Compact Bone
5. Blood
Blood
D: red and white blood cells in a fluid matrix
F: transports gases, waste, nutrients, etc
L: in blood vessels
Fig05.20
Red blood
cells
Plasma
(extracellular
matrix of blood)
Platelets
White blood
cell
(a) (b)©The McGraw-Hill Companies, Inc./Dennis Strete, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood
Red Blood Cells and Lymphocytes
Neutrophils and Eosinophils
Muscle Tissue
General Characteristics:
• Highly cellular
• Very vascular
• Muscle fibers can contract and are
responsible for most movement in the
body
Muscle Tissue
General Characteristics:
• Cells elongated
• Cells close together with little extracellular
material
• Does NOT regenerate well, usually
replaced with connective tissue
Types of Muscle Tissue (3)
1. Skeletal
• D: long, cylindrical, multinucleate cells,
and striated
• F: voluntary movement, locomotion,
generate heat when they contract
• L: attached to bone
62
Fig05.21
Striations
Portion of a
muscle fiber
Nuclei
(a) (b)©The McGraw-Hill Companies, Inc./Al Telser, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Skeletal muscle (l.s.), 400x, demonstrating peripheral nuclei and banding pattern of
skeletal muscle
Types of Muscle Tissue (3)
2. Smooth
• D: spindle-shaped, uninucleate cells,
arranged closely to form sheets, NO
STRIATIONS
• F: involuntary, move substances along
internal passageways
• L: walls of hollow organs, stomach,
gallbladder, urinary bladder
65
Fig05.22
Nucleus
Cytoplasm
(a) (b)©The McGraw-Hill Companies, Inc./Dennis Strete, photographer
Copyright ©The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Smooth muscle (x.s. and l.s. small intestine) 400x, demonstrating size
variation and cell shape.
Types of Muscle Tissue (3)
3. Cardiac
• D: branching, uninucleate cells, appears
striated, fit together at junctions called
intercalated discs
• F: involuntary, contractions propel blood
into circulation
• L: bulk of the heart wall known as the
myocardium
68
Fig05.23
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Intercalated
disc
Nucleus
Striations
(a) (b)©The McGraw-Hill Companies, Inc./Al Telser, photographer
Cardiac muscle (l.s.), 400x, demonstrating smaller size of cardiac cells,
central, single nucleus, and intercalated discs
Nervous Tissue
General Characteristics:
• Main component of the nervous system
• Aware of our external environment
• Longest cells in the body
• Limited ability to repair themselves after
an injury
Nervous Tissue
General Characteristics:
Contain two major cell types:
1. Neuron: highly specialized that generate
and conduct nerve impulses
2. Neuroglia: supporting cells, insulate and
protect neurons
The Neuron
Dendrite: carries messages/impulses to the nerve cell body
Axon:
The single fiber
that carries impulses
away from the body
Myelin: insulating matter that
covers the axon
Soma
Nucleus
Schwann cell
Node of
Ranvier
Axon
Terminal
Nervous Tissue
• D: Neurons and neuroglia
• F: Regulate and control body functions
• L: Brain, spinal cord, and nerves
74
Fig05.24
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(a) (b)
Nucleus
Cell
membrane
Cytoplasm
Cellular
process
Nuclei of
neuroglia
©Royalty-Free/Corbis
Nervous tissue (Purkinje cell of cerebellum), 1000x
Membranes
• Membranes are thin sheets of tissue
• They are made of both epithelial tissue
and connective tissue
• Cover body surfaces and line body
cavities
Epithelial Membranes
4 Types
1. Serous
2. Mucous
3. Cutaneous
4. Synovial
1. Serous Membrane
• Line body cavities that lack openings to
the outside
– thorax
– abdomen
– cover the organs in these cavities
• Secrete a thin, watery lubricant (serous
fluid) so organs can move with minimum
friction
2. Mucous Membrane
• Line cavities and tubes that open to the outside of the body
– oral and nasal cavities
– tubes of digestive, respiratory, urinary, and reproductive
• Produce a thick and sticky substance called mucus
3. Cutaneous Membrane
• Known as the skin
• Has an outer layer of epithelium
• Complex
4. Synovial Membrane
• Made of connective tissue
• Lines joints
• We will discuss more in the skeletal
system