Chapter 4: Tissues Flashcards
1
Q
Tissue
A
group of cells that work together to perform a common or related function
2
Q
What are the four basic types of tissues?
A
epithelial (covers and lines), connective (supportive), muscle (contracts), nervous (controls)
3
Q
What is the study of tissues?
A
histology
4
Q
What are the steps of tissue preparation?
A
fixed (preserving the cell/tissue), cut into thin sections, stain them
5
Q
Types of Microscopy
A
light microscope (compound: has ocular and objective lens); transmission electron microscopy (TEM); scanning electron microscope (SEM)
6
Q
Epithelial Tissues
A
epithelium or epithelia; covers body surfaces, lines body cavities and forms glands
7
Q
What are the characteristics of epithelial tissue?
A
exhibits polarity (having a apical and basal surface); forms continuous sheets; cells held together via tight junctions and desmosomes ; attached to a basement membrane that sit a top connective tissues; avascular and innervated; able to regenerate
8
Q
Basal Surface
A
lower surface; attached to the basement membrane
9
Q
Apical Surface
A
uppermost portion; is normally open to outside or a body cavity
10
Q
Epithelial cells always sit on…..
A
connective tissue
11
Q
Avascular
A
lack of or without blood vessels
12
Q
Innervated
A
has nerves
13
Q
How does the epithelial tissue get its nutrients?
A
since it is avascular the cells must get it from the connective tissue below basal layer; the nutrients diffuse into the cells; if it is a thick layer of cells the further away the cells are from the basal layer the less nutrients they get
14
Q
What is the classification of epithelial cells based on?
A
number of cell layers (simple or stratified) and shape of cells on the apical surface (squamous, cuboidal, columnar)
15
Q
Simple epithelial
A
one layer
16
Q
Stratified Epithelial
A
two or more layers
17
Q
Squamous Epithelial
A
flattened shape
18
Q
Cuboidal Epithelial
A
cube shaped
19
Q
Columnar Epithelial
A
column shape
20
Q
Description of Simple Squamous Epithelium
A
single layer of flattened cells with disc shaped central nuclei and sparse cytoplasm; the simplest of the epithelia
21
Q
Function of Simple Squamous Epithelium
A
allows materails to pass by diffusion and filtration in sites where protection is not important; secretes lubricating substances in serosae (linings of ventral body cavity)
22
Q
Location of Simple Squamous Epithelium
A
kidney glomeruli; air sacs of the lungs; lining of heart; blood vessels, and lympahtic vessels; serosae
23
Q
Endothelium
A
lining of blood vessels and heart; simple squamous associated with cardiovascular
24
Q
Description of Simple Cuboidal Epithelium
A
single layer of cubelike cells with large spherical central nuclei; about as wide as they are long
25
Function of Simple Cuboidal Epithelium
secretion and absorption
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Location of Simple Cuboidal Epithelium
kidney tubules, ducts and secretory portions of small glands; ovary surface
27
Description of Simple Columnar Epithelium
single layer of tall cells with round to oval nuclei; many cells bear microvilli, some bear cilia; layer may contain mucus-secreting unicellular glands (goblet cells)
28
Function of Simple Columnar Epithelium
absorption; secretion of mucus, enzymes and other substances; ciliated type propels mucus (or reproductive cells) by ciliary action
29
Location of Simple Columnar Epithelium
nonciliated type lines most of the digestive tract (stomach to rectum), gall bladder, and excretory ducts of some glands; ciliated variety lines small bronchi, uterine tubes, and some regions of the uterus
30
Goblet Cells
single cell gland that produces mucus; found in columnar of digestive system
31
Description of Pseudostratified Ciliated 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
32
Function of Pseudostratified Ciliated Columnar Epithelium
secrete substances, particularly mucus; propulsion of mucus by ciliary action
33
Location of Pseudostratified Ciliated Columnar Epithelium
ciliated variety lines the trachea and most of the upper respiratory tract; nonciliated type in males sperm carrying ducts and ducts of large glands
34
Description of Stratified Squamous Epithelium
thick epithelium 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
35
Function of Stratified Squamous Epithelium
protects underlying tissues in areas subjected to abrasion
36
Location of Stratified Squamous Epithelium
nonkeratinized type form moist linings of the esophagus, mouth, and vagina; keratinized variety forms the epidermis of the skin, a dry epithelium
37
Keratin
protein, protectant, waterproofer
38
Description of Transitional Epithelium
resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar; surface cells dome shaped or squamous like, depending on degree of organ stretch
39
Function of Transitional Epithelium
stretches readily, permits stored urine to distend urinary organ
40
Location of Transitional Epithelium
lines the ureters, bladder and part of the urethra
41
Gland
one or more cells specialized to secrete a product
42
What are the two types of glands?
the types are based on where secretions are released; endocrine and exocrine
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Endocrine Glands
secrete hormones into interstitial fluid (exocytosis); hormones transported via blood stream; ex) thyroid gland, pancreas, adrenal gland, testes, ovaries
44
Exocrine Glands
more numerous; secretes products onto surfaces or into body cavities; unicellular or multicellular
45
Multicellular glands....
have ducts that empty their products
46
Example of a Unicellular gland
goblet cell
47
Pancreas is...
both a endocrine and exocrine gland; pancreas produces insulin and releasing hormones
48
Connective Tissues
most abundant and widely distributed tissue in the body
49
Characteristics of Connective Tissues
all connective tissues originate from mesenchyme (embryonic tissue); consists mainly of nonliving extracellular matrix (ECM) ;cells are not connected to each other; avascular and vascular ( some are more vascular than others and some are avascular)
50
What are the structural components of connective tissue?
ground substance, protein fibers, cells,
51
Ground Substance
fills spaces between cells; contains fibers; varies from solid (like bone) to liquid
52
What are the types of protein fibers?
collagen, elastic fibers, and reticular fibers
53
Collagen
thick and tough; strongest and most abundant; in all connective tissue to varying degrees
54
Elastic Fibers
thin and rubber like; provide elasticity (stretch and recoil)
55
Reticular Fibers
thin, short, and branched; provide supports
56
What are the different types of cells in connective tissue?
fibroblasts, chondroblasts, osteoblasts, adipocytes, white blood cells, red blood cells, macrophages
57
Fibroblasts
secrete ground substances and fibers of connective tissue proper; mature to form fibrocytes (maintain the health of the matrix); go from fibroblasts to fibrocytes but can go back to fibroblasts if tissue is damaged
58
Chondroblastic
secrete ground substance and fibers of cartilage; mature to form chondrocytes (maintain health of matrix)
59
Osteoblasts
secrete ground substance and fibers of bone; mature to form osteocytes (maintain the health of the matrix)
60
Adipocytes
fat cells; store energy long term
61
White Blood Cells
WBC; defense cells of the blood
62
Red Blood Cells
RBC; oxygen transporting cells of blood; do not transport CO2 blood plasma transports CO2
63
Macrophages
large, phagocytic cells that devour foreign materials and cellular debris
64
Spleen
filters out dying RBC and recycles them to bone to make more RBC
65
What are the two types of connective tissue proper?
loose and dense
66
What are the types of loose connective tissue proper?
areolar, adipose, and reticular
67
What are the types of dense connective tissue proper?
regular, irregular, elastic
68
What are the types of cartilage?
hyaline, elastic, fibrocartilage
69
What are the types of connective tissue (the broad categories not the subcategories)?
connective tissue proper, cartilage, bone, blood
70
Description of Areolar Tissue
loose connective tissue proper; gel like matrix with all three fiber types; cells- fibroblasts, macrophages, mast cells, and some WBC
71
Function of Areolar Tissue
wraps and cushions organs; its macrophages phagocytize bacteria; plays important role in inflammation; holds and conveys tissue information
72
Location of Areolar Tissue
widely distributed under epithelia of body, forms lamina propria of mucous membranes; packages organs; surround capillaries
73
Description of Adipose Tissue
loose connective tissue proper; matrix as in areolar, but very sparse; closely packed adipocytes ,or fat cells, have nucleus pushed to the side by large fat droplet
74
Function of Adipose Tissue
provides reserve food fuel; insulates against heat loss; supports and protects organs
75
Location of Adipose Tissue
under skin in subcutaneous tissue; around kidneys and eyeballs; within abdomen in breasts
76
Description of Reticular Tissue
loose network of reticular fibers in a gel-like ground substance; reticular cells lie on the fibers
77
Function of Reticular Tissue
fibers form a soft internal skeleton (stroma) that supports other cell types including WBC, mast cells, and macrophages
78
Location of Reticular Tissue
lymphoid organs (lymph nodes, bone marrow, and spleen)
79
Description of Dense Regular Tissue
primarily parallel collagen fibers; a few elastic fibers; major cell type is fibroblast; nuclei are flat
80
Function of Dense Regular Tissue
attaches muscles to bones or to muscles (tendons); attaches bone to bone (ligaments); with stands great tensile strength when pulling force is applied in one direction
81
Location of Dense Regular Tissue
tendons, most ligaments, aponeuroses
82
Description of Dense Irregular Tissue
irregularly arranged collagen fibers; some elastic fibers; fibroblast is the major cell
83
Function of Dense Irregular Tissue
withstands tension excerted in many directions; provides structural strength
84
Location of Dense Irregular Tissue
fibrous capsules of organs and of joints; dermis of the sking; submucosa of digestive tract
85
Elastic Tissue (dense)
dense regular connective tissue containing a high proportion of elastic fibers
86
Function of Elastic Tissue
allows tissue to recoil after stretching; maintains pulsatile flow of blood through arteries; aids passive recoil of lungs following inspiration
87
Location of Elastic Tissue
aorta, walls of large arteris
88
What are the three types of cartilage?
hyaline, elastic, fibrocartilage
89
Description of Hyaline Cartilage
amorphus but firm matrix; collagen fibers form an imperceptible network; chondroblasts produce the matrix and when mature (as chondrocytes) lie in lacunae
90
Function of Hyaline Cartilage
supports and reinforces; serves as resilient cushion; resists compressive stress
91
Location of Hyaline Cartilage
covers ends of long bones; connects ribs to sternum; cartilage of the nose, trachea, and larynx, most of embryonic skeleton
92
Description of Elastic Cartilage
similar to hyaline cartilage, but more elastic fibers in matrix
93
Function of Elastic Cartilage
maintains the shape of a structure while allowing great flexibility
94
Location of Elastic Cartilage
supports the external ear (pinna); epiglottis
95
Description of Fibrocartilage
matrix similar to but less firm than that in hyaline cartilage; thick collagen fibers; nucleus is NOT FLAT do not confuse with dense regular
96
Function of Fibrocartilage
tensile strength allows it to absorb compressive shock
97
Location of Fibrocartilage
intervertebral discs; pubic symphysis; discs of knee joint
98
Description of Bone
hard calcified matrix containing many collagen fibers; osteocytes lie in lacunae; very well vascularized
99
What cell is associated with cartilage?
chondroblasts/chondrocytes
100
What cell is associated with bone?
osteocytes
101
What tissue is fibroblasts typically associated with?
connective tissue proper
102
Function of Bone
supports and protects (by enclosing); provides levers for the muscles to act on; stores calcium and other minerals and fat; marrow inside bones is the site for blood cell formation
103
Description of Blood
red and white blood cells in a fluid matrix
104
Function of Blood
transports respiratory gases, nutrients, wastes and other substances
105
What is the shape of a red blood cell?
biconcave disk; the middle is thin
106
Muscle Tissues
contracts to cause movement
107
Characteristics of Muscle Cells
muscle fibers (cells) tightly packed together (not much matrix); voluntary or involuntary; well vascularized
108
Description of Skeletal Muscle
long, cylindrical, multinucleate cells; obvious striations, large cells
109
Function of Skeletal Muscle
voluntary movement; locomotion; manipulatioin of the environment; facial expression; voluntary control
110
Location of Skeletal Muscle
in skeletal muscles attached to bones or occasionally skin
111
Description of Cardiac Muscle
branching, striated, generally uninucleate cells that connect at specialized junctions (intercalated discs)
112
Function of Cardiac Muscle
as it contracts, it propels blood into the circulation; involuntary control
113
Location of Cardiac Muscle
walls of the heart
114
Intercalated Discs
are where the connections of two cardiac cells meet; gap junctions
115
Description of Smooth Muscle
cells are spindle shaped (tapered on both ends) with central nuclei; no striations; cells arranged closely to form sheets
116
Function of Smooth Muscle
propel substances or object (foodstuffs, urine, a baby) along internal passageways; involuntary control; it propels things in a wave like manner
117
Location of Smooth Muscle
mostly in the walls of hollow organs; such as digestive system
118
Nervous Tissue
regulates and controls most body functions
119
What are the characteristics of nervous tissue?
two cells types: neurons and neuroglia (or glial cells); vascularized
120
Neurons
highly specialized; excitable with a high metabolic rate; extremely long lived; amitotic; can not replace/regenerate
121
Neuroglia
aka glial cells; supports, insulate, and protect neurons
122
Description of 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 nonexcitable supporting cells
123
Function of Nervous Tissue
neurons transmit electrical signals from sensory receptors and to effectors (muscles and glands); supporting cells support and protect neurons
124
Location of Nervous Tissue
brain, spinal cord, nerves
125
What are the covering and lining membranes?
continuous sheets consisting of a epithelium and connective tissue; cutaneous membrane, mucous membrane, and serous membranes
126
Cutaneous Membrane
skin; dry membrane; keratinized stratified squamous epithelium (epidermis) and connective tissue (dermis); protective
127
Mucous Membrane
mucosae; wet membranes; lines body cavities that open to the outside; stratified squamous or simple columnar epithelia and areolar connective tissue (lamina propria); absorption and secretion (usually mucous)
128
Serous Membranes
wet membranes; lines body cavities that are closed to the outside; parietal and vesceral layers separated by serous fluid; simple squamous epithelium and areolar connective tissue; lubrication
129
What tissues regenerate excellent?
epithelia tissues, bone, areolar connective tissue, and blood forming tissue
130
What tissues regenerate moderately?
smooth muscle, dense regular connective tissue (tendons and ligaments)
131
What tissues regenerate poorly?
skeletal and cartilage
132
What tissues do not regenerate?
cardiac and nervous tissue; destroyed tissue replaced with scar tissue
133
What are the steps of tissue repair?
inflammation, organization, regeneration
134
Inflammation
first step of tissue repair; injured cells release inflammatory chemicals which make local blood vessels leaky; WBCs, fluid, and clotting proteins seep into the area; clotting seals off area; clot forms scab
135
Organization
second step of tissue repair; restores blood supply; capillaries grow into area and clot is replaced by granulation tissue (type of new connective tissue); fibroblasts multiply and produce growth factors and collagen fibers; macropahges phagocytize dead and dying cells and other debris; surface epithelial cells dvidied and migrate over granulation tissue
136
Regeneration
final step of tissue repair; collagen fibers of fibrosed area contract, pulling margins of wound together; epithelial cells divide forming a thick layer under scab which detaches
