Chapter 4 Study Skills: Key Terms

Helpfulness: 0
Set Details Share
Page to share:
Embed this setcancel
COPY
code changes based on your size selection
Size:
X
Show:
1

Tissue

Groups of cells that are similar in structure and perform a common or related function

2

What are the four primary tissue types?

Epithelial, connective, muscle, nervous

3

What are the roles of the four tissue types?

Epithelial tissue COVERS, connective tissue SUPPORTS, muscle tissue PROVIDES MOVEMENT, and nervous tissue CONTROLS

4

What three things must occur before a specimen can be viewed through a microscope?

Fixation (preserved), Sectioning (cut into slices thin enough to transmit light/electrons), and Staining (dyed with colored synthetic dyes to enhance contrast)

5

Artifacts

Minor distortions in microscope specimens that are the result of their exposure to many procedures that alter their original condition

6

Histology

Study of tissues

7

Nervous Tissue

Internal communication;

Brain, spinal cord, nerves

8

Muscle Tissue

Contracts to cause movement

Muscles attached to bones (skeletal), muscles of the heart (cardiac), muscles of walls or hollow organs (smooth)

9

Epithelial Tissue/Epithelium

A sheet of cells that covers a body surface or lines a body cavity; Forms boundaries between different environments, protects, secretes, absorbs, filters

Lining of the digestive tract organs/other hollow organs, skin surface (epidermis)

10

Connective Tissue

Supports, protects, binds other tissues together

Bones, tendons, fat and other soft padding tissue

11

What are the two forms of epithelial tissue that occur in the body?

Covering/lining epithelium and Glandular epithelium

12

Covering/Lining Epithelium

Forms the outer layer of the skin; dips into and lines the open cavities of the urogenital, digestive, and respiratory systems; covers the walls and organs of the closed ventral body cavity

13

Glandular Epithelium

Fashions the glands of the body

14

What are the main functions of the epithelium?

Protection, absorption, filtration, excretion, secretion and sensory reception

15

Apical Surface

On an epithelium: an upper free surface exposed to the body exterior or the cavity of an internal organ; most are smooth, but some have microvilli

16

Basal Surface

On an epithelium: lower attached surface to the apical surface, faces inward toward the body, attaches to the connective tissue

17

Why do we say that the apical and basal surfaces exhibit apical-basal polarity?

Because the two surfaces differ in both structure and function

18

Microvilli

Fingerlike extensions of the plasma membrane; greatly increase the exposed surface area

19

Cilia

Tiny, hairlike projections that propel substances along their free surface

20

Basal Lamina

Noncellular, adhesive sheet adjacent to the basal surface of an epithelium that consists largely of glycoproteins secreted by the epithelial cells plus some fine collagen fibers; acts as a selective filter that determines which molecules diffusing from the underlying connective tissue are allowed to enter the epithelium; acts as scaffolding along which epithelial cells can migrate to repair wounds

21

What is the purpose of tight junctions in epithelial tissues?

To help keep proteins in the apical region of the plasma membrane from diffusing into the basal region, thus helping maintain epithelial polarity

22

Reticular Lamina

Deep to the basal lamina; a layer of extracellular material containing a fine network of collagen protein fibers

23

Basement Membrane

Formed by the basal and reticular laminae; reinforces the epithelial sheet and helps it resist stretching and tearing, defines the epithelial boundary

24

What are the special characteristics of epithelial tissues?

Polarity, specialized contacts, supported by connective tissues, avascular but innervated, high regenerative capacity

25

Epithelium is ____ (vascular/avascular) but ______ (innervated/not innervated)

Avascular, innervated

26

Does epithelium have a high or low regenerative capacity?

High

27

How is epithelium classified?

Two names: first indicates the number of cell layers present, the second describes the shape of the cells

28

Simple Epithelia

Consists of a single cell layer; typically found where absorption, secretion, and filtration occur and a thin epithelial barrier is desirable

29

Stratified Epithelia

Composed of two or more cell layers stacked on top of each other; common in high-abrasion areas where protection is important (i.e.: skin surface, lining of the mouth)

30

Squamous Cells

Flattened and scale-like

Nucleus is a flattened disc

31

Cuboidal Cells

Boxlike, approximately as tall as they are wide

Nucleus is spherical

32

Columnar Cells

Tall and column-shaped

Nucleus is elongated from top to bottom, located closer to the cell base

33

According to what layer are stratified epithelia named and why?

They're named according to the shape of the cells in the APICAL layer because cell shape differs in the different layers

34

Simple Squamous Epithelium

Single layer of flattened cells wit disc-shaped central nuclei, sparse cytoplasm; simplest of the epithelia

35

Where is Simple Squamous Epithelium located?

Kidney glomeruli; air sacs of lungs; lining of the heart, blood vessels, and lymphatic vessels; lining of the ventral body cavity (serosae)

36

What is/are the function(s) of Simple Squamous Epithelium?

Allows materials to pass by diffusion and filtration in sites where protection is not important; secrets lubricating substances in serosae

37

Endothelium

A type of Simple Squamous Epithelium; provides a slick, friction-reducing lining in lymphatic vessels and in all hollow organs of the cardiovascular system (blood vessels, heart, and capillaries); exceptional thinness encourages the efficient exchange of nutrients and wastes between the bloodstream and surrounding tissue cells

38

Mesothelium

A type of Simple Squamous Epithelium; found in serous membranes (the membranes lining the ventral body cavity and covering its organs)

39

Simple Cuboidal Epithelium

Single layer of cuboidal cells with large, spherical central nuclei

40

What is/are the location(s) of Simple Cuboidal Epithelium?

Kidney tubules; ducts and secretory portions of small glands; ovary surface

41

What is/are the function(s) of Simple Cuboidal Epithelium?

Secretion and absorption

42

Simple Columnar Epithelium

Single layer of tall cells with round to oval nuclei; many cells bear microilli, some bear cilia; layer may contain mucus-secreting unicellular glands (goblet cells)

43

What is/are the location(s) of Simple Columnar Epithelium?

Nonciliated type lines most of the digestive tract (stomach to rectum), gallbladder, and excretory ducts of some glands; ciliated variety lines small bronchi, uterine tubes, and some regions of the uterus

44

What is/are the function(s) of Simple Columnar Epithelium?

Absorption, secretion of mucus, enzymes, and other substances; ciliated type propels mucus (or reproductive cells) by ciliary action

45

What two distinct modifications make the digestive tract lining ideal for the dual function of absorption and secretion?

Dense microvilli on the apical surface of absorptive cells and tubular glands that are made primarily of cells that secrete mucus-containing intestinal juice

46

Pseudostratified Columnar Epithelium

Single layer of cells of differing heights, some not reaching the free surface; nuclei seen at different levels; may contain mucus-secreting cells and bear cilia

47

Location(s) of Psuedostratified Columnar Epithelium

Nonciliated type in sperm-carrying ducts and ducts of large glands; ciliated variety lines the trachea, most of the upper respiratory tract

48

Function(s) of Psuedostratified Columnar Epithelium

Secret substances, particularly mucus; propulsion of mucus by ciliary action

49

Stratified Squamous Epithelium

Thick membrane composed of several cell layers; basal cells are cuboidal or columnar and metabolically active; surface cells are flattened (squamous); in the keratinized type, the surface cells are full of keratin and dead; basal cells are active in mitosis and produce the cells of the more superficial layers

50

Location(s) of Stratified Squamous Epithelium

Nonkeratinized type forms the moist linings of the esophagus, mouth, and vagina; keratinized variety forms the epidermis of the skin, a dry membrane

51

Function(s) of Stratified Squamous Epithelium

Protects underlying tissues in areas subjected to abrasion

52

Transitional Epithelium

Resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnal; surface cells dome shaped or squamous-like, depending on degree of organ stretch

53

Location(s) of Transitional Epithelium

Lines the ureters, bladder, and part of the urethra

54

Function(s) of Transitional Epithelium

Stretches readily, permits stored urine to distend urinary organ

55

Gland

Consists of one or more cells that make and secrete a particular product

56

Secretion

Aqueous fluid that usually contains proteins, but can be lipid- or steroid-rich

57

According to what two traits are glands classified?

Where they release their product, and the number of cells they have

58

Endocrine glands

"internally excreting"; often called ductless glands; produce hormones that are secreted by exocytosis directly into the extracellular space; most are compact multicellular organs, some individual hormone-producing cells are scattered in the digestive tract lining and in the brain

59

Hormones

Messenger chemicals secreted by endocrine glands

60

Exocrine glands

"externally excreting"; secrete products onto body surfaces or into body cavities; unicellular glands use exocytosis, multicellular glands use an epithelium-walled duct that transports the secretion to the epithelial surface

61

Unicellular

"one-celled"

62

Mucin

complex glycoprotein produced by unicellular exocrine glands that dissolves in water when secreted to produce mucus

63

Goblet Cells

Mucus-secreting unicellular exocrine glands

64

Multicellular

"many-celled"

65

What are the two basic parts of multicellular exocrine glands?

An epithelium-derived duct and a secretory unit (acinus) consisting of secretory cells

66

How are multicellular exocrine glands classified?

Simple or compound

67

Simple Glands

have an unbranched duct

68

Compound Glands

have a branched duct

69

Tubular

Secretory units are tubular if the secretory cells form tubes

70

Alveolar/Acinar

Secretory units are alveolar if the secretory cells form small, flask-like sacs

71

Tubuloalveolar

Secretory units are tubuloalveolar if they are both tubular and alveolar

72

Merocrine Glands

Glands that secret their products by exocytosis as they are produced

73

Holocrine Glands

Glands that accumulate their products within secretory cells until they rupture

74

What are the four main classes of connective tissue?

Connective Tissue Proper, Cartilage, Bone, and Blood

75

What are the three characteristics that set connective tissues apart from other primary tissues?

Common origin, degrees of vascularity, and extracellular matrix

76

What is the common origin of connective tissues?

All connective tissues arise from mesenchyme (an embryonic tissue)

77

What are the different degrees of vascularity in connective tissues?

Cartilage is avascular, dense connective tissue is poorly vascularized, and other types of connective tissue are richly vascularized

78

Extracellular Matrix

Non-living material that composes connective tissues

79

What are the benefits of the extracellular matrix in connective tissues?

Connective tissues can bear weight, withstand great tension and endure abuses such as physical trauma and abrasion that no other tissue can tolerate

80

What are the three main structural elements of connective tissues?

ground substance, fibers, and cells

81

Ground Substance

Unstructured material that fills the space between the cells and contains the fibers of connective tissues; consists of large amounts of fluid and functions as a molecular medium through which nutrients and other dissolved substances can diffuse between the blood capillaries and the cells

82

What are the three types of connective tissue fibers and what are they composed of, respectively?

Collagen fibers, collagen; Elastic fibers, elastin; Reticular fibers, collagen

83

What type of connective tissue fibers are strongest and most abundant?

Collagen fibers

84

Fibroblasts

Cells of the connective tissue proper

85

Chondroblasts

Cells of the cartilage

86

Osteoblasts

Cells of the bones

87

Mast Cells

Typically cluster along blood vessels; detect foreign organisms and initiate the local inflammatory responses against them

88

Macrophages

Large, irregularly shaped cells that avidly devour a broad variety of foreign materials and dispose of dead tissue cells

89

What are the two subclasses of connective tissue proper?

Loose connective tissues and dense connective tissues

90

What are the three types of loose connective tissue?

Areolar, Adipose, Reticular

91

Areolar Tissue

Gel-like matrix with all three fiber types

Cells: fibroblasts, macrophages, mast cells, and some white blood cells

92

Function(s) of Areolar Tissue

Wraps and cushions organs; macrophages phagocytize bacteria; plays important role in inflammation; holds and conveys tissue fluid; storing nutrients as fat in adipocytes (fat cells)

93

Location(s) of Areolar Tissue

Widely distributed under epithelia of the body (e.g. forms lamina propria of mucous membranes; packages organs; surrounds capillaries

94

Adipose Tissue

Matrix as in areolar, but very sparse; closely packed adipocytes (fat cells), have nucleus pushed to the side by large fat droplet; richly vascularized

95

Function(s) of Adipose Tissue

Provides reserve food fuel; insulates against heat loss; supports and protects organs

96

Location(s) of Adipose Tissue

Under skin in subcutaneous tissue; around kidneys and eyeballs; within abdomen; in breasts

97

Adipocytes

Fat cells

98

What are the two types of adipose tissue?

White adipose tissue and Brown adipose tissue

99

White Adipose Tissue

Store nutrients

100

Brown Adipose Tissue

Rich in mitochondria that use the lipid fuels to heat the bloodstream to warm the body

101

Reticular Tissue

Loose network of reticular fibers in a gel-like ground substance; reticular cells lie on the network

102

Function(s) of Reticular Tissue

Fibers form a soft internal skeleton (stroma) that supports other cell types including white blood cells, mast cells, and macrophages

103

What are the three types of dense connective tissue?

Dense Regular, Dense Irregular, and Elastic

104

Dense Regular Connective Tissue

Primarily parallel collagen fibers; a few elastic fibers; major cell type is the fibroblast

105

Function(s) of Dense Regular Connective Tissue

Attaches muscles to bones or to muscles; attaches bones to bones; withsands great tensile stress when pulling force is applied in one direction

106

Location(s) of Dense Regular Connective Tissue

Tendons, most ligaments, aponeuroses

107

Aponeuroses

Flat, sheetlike tendons that attach muscles to other muscles or to bones

108

Dense Irregular Connective Tissue

Primarily irregularly arranged collagen fibers; some elastic fibers; fibroblast is the major cell type

109

Function(s) of Dense Irregular Connective Tissue

Withstands tension exerted in many directions; provides structural strength

110

Location(s) of Dense Irregular Connective Tissue

Fibrous capsules of organs and of joints; dermis of the skin; submucosa of the digestive tract

111

Elastic Connective Tissue

Dense regular connective tissue containing a high proportion of elastic fibers

112

Function(s) of Elastic Connective Tissue

Allows tissue to recoil after stretching; maintains pulsatile flow of blood through arteries; aids passive recoil of lungs following inspiration

113

Location(s) of Elastic Connective Tissue

Walls of large arteries; within certain ligaments associated with the vertebral column; within the walls of the bronchial tubes

114

Cartilage

Connective tissue that stands up to both tension and compression; has qualities that are between those of dense connective tissue and bone; tough but flexible, lacks nerve fibers and is avascular; main cell type is chondrocytes

115

How does cartilage receive its nutrients?

Diffusion from blood vessels located in the connective tissue layer (perichondrium) surrounding it

116

Hyaline Cartilage

Amorphous but firm matrix; collagen fibers form an imperceptible network; chondroblasts produce the matrix and when mature (chondrocytes) lie in lacunae

117

Function(s) of Hyaline Cartilage

Supports and reinforces; serves as resilient cushion; resists compressive stress

118

Location(s) of Hyaline Cartilage

Forms most of the embryonic skeleton; covers the ends of long bones in joint cavities; forms costal cartilages of the ribs; cartilages of the nose, trachea, and larynx

119

Elastic Cartilage

Similar to hyaline cartilage, but more elastic fibers in matrix

120

Function(s) of Elastic Cartilage

Maintains the shape of a structure while allowing great flexibility

121

Location(s) of Elastic Cartilage

Supports the external ear (pinna); epiglottis; found where strength and exceptional stretchability are needed

122

Fibrocartilage

Matrix similar to but less firm than that in hyaline cartilage; thick collagen fibers predominate

123

Function(s) of Fibrocartilage

Tensile strength allows it to absorb compressive shock

124

Location(s) of Fibrocartilage

Intervertebral discs; pubic symphysis; discs of knee joint; where strong support and the ability to withstand heavy pressure are required

125

Bone (Osseous Tissue)

Hard, calcified matrix containing many collagen fibers; osteocytes lie in lacunae; very well vascularized; has an exceptional ability to support and protect body structures

126

Function(s) of Bone (Osseous Tissue)

Supports and protects (by enclosing); provides levesr for the muscles to act on; stores calcium and other minerals and fat; marrow inside bones is the site for blood cell formation (hematopoiesis)

127

Hematopoiesis

Blood cell formation

128

Blood

Red and white blood cells in a fluid matrix (plasma)

129

Function(s) of Blood

Transport respiratory gases, nutrients, wastes, and other substances

130

Location of Blood

Contained within the blood vessels

131

Muscle Tissues

Highly cellular, well-vascularized tissues that are responsible for most types of body movement

132

Myofilaments

Elaborate networks of the actin and myosin filaments that bring about movement or contraction in all cell types

133

What are the two classifications of muscle tissue?

Voluntary muscle and involuntary muscle

134

Voluntary Muscle

Muscle whose contraction is under our conscious control

135

Involuntary Muscle

Muscle whose contraction is not under our conscious control

136

What are the three types of muscle tissue?

Skeletal, Cardiac, and Smooth

137

Skeletal Muscle Tissue

Long, cylindrical, multinucleate cells; obvious striations; form the flesh of the body

138

Function(s) of Skeletal Muscle Tissue

Voluntary movement; locomotion; manipulation of the environment; facial expression; voluntary control

139

Location(s) of Skeletal Muscle Tissue

In skeletal muscles attached to bones or occasionally to skin

140

Cardiac Muscle Tissue

Branching, striated, generally uninucleate cells that interdigitate at specialized junctions (intercalated discs)

141

Function(s) of Cardiac Muscle Tissue

As it contracts, it propels blood into the circulation, through the blood vessels to all parts of the body; involuntary control

142

Location of Cardiac Muscle Tissue

The walls of the heart

143

Smooth Muscle Tissue

Spindle-shaped (elongated) cells with central nuclei; no striations; cells arranged closely to form sheets

144

Function(s) of Smooth Muscle Tissue

Propels substances or objects (foodstuffs, urine, a baby) along internal passageways; involuntary control

145

Location(s) of Smooth Muscle Tissue

Mostly in the walls of hollow organs other than the heart

146

Nervous Tissue

Neurons are branching cells; cell processes that may be quite long extend from the nucleus-containing cell body; also contributing to nervous tissue are non-excitable supporting cells

147

Function(s) of Nervous Tissue

Neurons transmit electrical signals from sensory receptors and to effectors (muscles and glands); supporting cells support and protect neurons

148

Location(s) of Nervous Tissue

Brain, spinal cord, and nerves

149

Neurons

Highly specialized nerve cells that generate and conduct nerve impulses

150

What are the functions of neurons?

Respond to stimuli, transmit electrical impulses over substantial distances within the body

151

Mucous Membranes (Mucosae)

Membranes that line all of the body cavities that open to the outside of the body

i.e.: the hollow organs of the digestive, respiratory, and urogenital tracts

152

Lamina Propria

Layer of loose connective tissue over which the simple columnar epithelial sheet of the mucosae lies

153

Serous Membranes (Serosae)

Moist membranes found in closed ventral cavities; consists of simple squamous epithelium resting on a thin layer of loose connective (areolar) tissue, which results in the thin clear serous fluid that lubricates the facing surfaces of the parietal and visceral layers so they slide across each other easily

154

Pleurae

Serosae that lines the thoracic wall and covers the lungs

155

Pericardium

Serosae that encloses the heart

156

Peritoneum

Serosae that encloses the abdominopelvic viscera

157

Inflammatory Response

Relatively nonspecific reaction that develops quickly wherever tissues are injured

158

Immune Responses

Extremely specific reactions that take longer to swing into action than inflammatory responses

159

What are the two ways in which tissue repair occurs?

Regeneration and Fibrosis

160

Regeneration

Form of tissue repair in which destroyed tissue is replaced with the same kind of tissue

161

Fibrosis

Form of tissue repair in which dense connective tissue proliferates to form scar tissue

162

What are the stages of Tissue Repair?

1) Inflammation sets the stage, 2) Organization restores the blood supply, 3) Regeneration and fibrosis effect permanent repair

163

What is the first step of Tissue Repair?

Inflammation sets the stage; tissue trauma causes capillaries to dilate, white blood cells and other inflammatory substances seep into the injured area

164

What is the second step of Tissue Repair?

organization restores the blood supply; blood clot is replaced by granulation tissue, which produce growth factors and new collagen fibers and later becomes scar tissue

165

What is the third step of Tissue Repair?

Regeneration and fibrosis effect permanent repair; surface epithelium begins to regenerate until it finally resembles the adjacent skin tissue; end result is a fully regenerated epithelium and an underlying area of scar tissue

166

What kinds of tissues have high regenerative capacity?

Epithelial tissues, bone, areolar connective tissue, dense irregular connective tissue, and blood-forming tissue

167

What kinds of tissues have moderate regenerative capacity?

Smooth muscle, dense regular connective tissue

168

What kinds of tissues have a weak regenerative capacity?

Skeletal muscle, cartilage

169

What kinds of tissues have no regenerative capacity?

Cardiac muscle, nervous tissue