Lab 1: Histology Flashcards
1
Q
What are the four primary tissues of the vertebrate body?
A
- Epithelial
- Connective
- Muscle
- Nervous
2
Q
What are the three functions of epithelial tissue?
A
- Covers the body surfaces
- Lines hollow organs, ventral body cavities, and ducts
- Forms glands
3
Q
What are the four functions of connective tissue?
A
- Protects and supports the body and its organs
- Binds organs together
- Stores energy
- Provides immunity
4
Q
Which tissue provides immunity?
A
Connective
5
Q
Which tissue forms glands?
A
Epithelial
6
Q
What is the function of muscle tissue?
A
Responsible for movement and the generation of force
7
Q
What is the function of nervous tissue?
A
Carries information very quickly from one side of the body to the other
8
Q
EVERY cell in our body belongs to one of how many tissue types?
A
Four (epithelial, connective, muscle, nervous)
9
Q
What are the two basic types of epithelial tissues?
A
- Covering and lining epithelia
- Glandular epithelia
10
Q
Differentiate covering and lining epithelia form glandular epithelia.
A
- Covering-Lining epithelial cells form a continuous layer over all the free surfaces of the body
- Glandular epithelia make up most of the glands in the body
11
Q
Where are covering-lining epithelial cells found?
A
- Outer layer of the skin
- Inner surface of the digestive and respiratory cavities
- Inner surface of the heart and blood vessels
- Walls and organs of closed ventral body cavities
- Ducts of exocrine glands
12
Q
Are epithelial cells close to each other or far away?
A
Close, there is little extracellular material between cells
13
Q
What types of junctions unite adjacent epithelial cells? (3)
A
- Tight junctions
- Desmosomes
- Gap junctions
14
Q
What is the apical surface? In which cells are they found? What is the exception?
A
- One free surface found in epithelial cells
- Exposed at the body surface or at the lumen (space) of the body cavity, duct, tube or vessel
- With the exception of endocrine glands
15
Q
What does the lower surface of an epithelium rest on? What is the exception?
A
- The basal surface rests on a basement membrane; a non-living adhesive material secreted by the epithelium and underlying connective tissue
- With the exception of endocrine glands
16
Q
Are there many or little blood vessels within the epithelial layer? What is the exception?
A
- There are NO blood vessels
- With the exception of endocrine glands
17
Q
How often do epithelial cells divide? Why? What is the exception?
A
- Frequent cell division because they are exposed to wear and tear and injury
- With the exception of endocrine glands
18
Q
What are the three primary functions of covering epithelia?
A
- Protect underlying tissues
- Allow and regulate the passage of materials
- Form sensory parts of organs
19
Q
What does epithelia protect from?
A
Physical damage, drying out, chemical injury, infection
20
Q
What materials are regulated by epithelia?
A
Oxygen, water, food, waste
21
Q
Specialized epithelia form sensory parts of organs, such as what?
A
Eye, ear, mouth (taste buds), nose (olfactory epithelium)
22
Q
Most glands are derived from which kinds of cells?
A
Epithelial cells specialized for producing secretions
23
Q
What is the material secreted from glands usually made of?
A
Watery fluid containing substances such as salts, enzymes, hormones, mucus, fats
24
Q
Give examples of products of glands.
A
Milk, insulin, sweat, saliva, calcitonin, tears, bile
25
What are the three features that allow the classification of covering and lining epithelia?
1. The number of cell layers
2. The shape of the cells
3. Specializations of their cell surfaces
26
Flat epithelium cells are called ______.
squamous
27
Square epithelium cells are called ______.
cuboidal
28
Rectangular epithelium cells are called ______.
columnar
29
Epithelium cells that change shape depending on the degree of stretching of the tissue are called _______.
transitional
30
Under a microscope, if nuclei are flat and parallel to the free surface, they are ______ epithelium.
squamous
31
Under a microscope, if nuclei are oval and parallel to the axis of the cell and situated at its base, they are ______ epithelium.
columnar
32
Under a microscope, if nuclei are round and situated in the middle of the cell, they are ______ epithelium.
cuboidal
33
Where are simple epithelia mainly found? What is their main function?
- Areas of minimum wear and tear
| - To allow passage of substances between the lumen and the surrounding tissues
34
What is the main function of stratified epithelia?
Protect the tissues that they cover
35
What are the four sub-classifications of simple epithelia?
- Squamous
- Cuboidal
- Columnar
- Pseudostratified
36
What are the four sub-classifications of stratified epithelia?
- Squamous
- Cuboidal
- Columnar
- Transitional
37
What kind of epithelium is found in the alveoli of the lungs, the kidney glomeruli, the lining of the heart, blood vessels and lymphatic vessels, and in the lining of the ventral body cavities?
Simple squamous epithelium
38
Which epithelium is the thinnest of them all? What does that allow?
- Simple squamous epithelium
| - Well-adapted for diffusion (gas exchange, exchange of waste and nutrients, filtration, secretion)
39
What kind of epithelium is found in small glands, kidney tubules and ovary surface?
Simple cuboidal epithelium
40
What is the simple cuboidal epithelium adapted for?
Secretion and absorption of substances; giving urine its final composition as it moves in and out of the tubule
41
Which simple epithelium may be ciliated or non-ciliated?
- Columnar
| - Pseudostratified
42
What do non-ciliated, simple columnar epithelium contain on the apical surface of its cells? What does that do?
- Microvilli on the apical surface of its cells
| - Increase the surface area of the epithelium
43
What kind of epithelium is found mainly lining the digestive tract, and lining the ducts of some glands?
Non-ciliated, simple columnar epithelium
44
What do ciliated, simple columnar epithelium contain on the apical surface of its cells?
Cilia
45
What kind of epithelium is found in the small bronchi, the uterine tubes and part of the uterus?
Ciliated, simple columnar epithelium
46
Which cells are involved in the secretion of mucus and in moving mucus or female reproductive cells?
Ciliated, simple columnar epithelium
47
Explain the composition of simple pseudostratified epithelium.
- One layer of cells
- All its cells rest on the basement membrane
- Appears stratified because cells are of different heights and their nuclei are at different levels
48
What kind of epithelium is found lining part of the male urethra and ducts of large glands?
Non-ciliated simple pseudostratified epithelium
49
What kind of epithelium is found in the trachea, primary bronchi and in most of the upper respiratory tract, and is involved in the secretion and propulsion of mucus?
Ciiliated simple pseudostratified epithelium
50
Which epithelium is the thickest of all? What is its function?
- Stratified squamous epithelium
| - Protection
51
Which epithelium cells may or may not contain keratin? What is keratin's function?
- Stratified squamous epithelium
- Tough protective protein that prevents water loss
- Resistant to friction
- Repels bacteria
52
What epithelium forms the epidermis of the skin?
Keratinized, stratified squamous epithelium
53
What kind of epithelium lines wet surfaces subjected to abrasion (lining of the mouth, esophagus, tongue, part of the epiglottis, vagina)?
Non-keratinized, stratified squamous epithelium
54
What kind of epithelium is found in the largest ducts of sweat glands, mammary glands, salivary glands and in parts of the male urethra? What is its function?
- Stratified cuboidal epithelium
| - Protection
55
What kind of epithelium is very rare, and lines part of the urethra, large ducts of some glands, and a portion of the conjunctiva of the eye? What are its functions?
- Stratified columnar epithelium
| - Protection and secretion
56
What kind of epithelium is found lining surfaces of organs subjected to stretch, such as the bladder, the ureters, and part of the urethra? What is its function?
- Stratified transitional epithelium
| - Allows for distension of the urinary organ
57
What does a transitional epithelium look like if it is stretched? What does it look like if it is unstretched?
- Stretched: stratified squamous epithelium
| - Unstretched: stratified cuboidal epithelium
58
Differentiate endocrine and exocrine glands.
- Endocrine: products (hormones) are secreted directly into the blood
- Exocrine: release their products onto the free surface of the skin or of the open cavities of the body (digestive, respiratory, reproductive tract)
59
Most of the endocrine glands are _______ derivatives.
epithelial
60
Describe how endocrine glands are formed.
- By invagination from an epithelial sheet and initially having ducts connecting them to the free surface of the epithelial sheet
- During embryonic development, they will lose their ducts and thus are called ductless glands
61
Under the microscope, what do endocrine glands look like? What is the major difference?
- Stratified epithelial tissues
| - They do NOT have a free surface, and are surrounded directly by other tissues
62
Are the cells of connective tissue close to each other or far away?
Far apart, separated by an abundant amount of extracellular matrix
63
Where do you find connective tissue?
Everywhere in the body
64
What are the four main functions of connective tissue?
1. Binding, support and packaging other tissues (epithelia, muscles, nerves)
2. Protection, defense and repair
3. Insulation
4. Transportation
65
What forms the three-dimensional fibrous mesh which supports cells inside large soft organs (liver, spleen)?
Connective tissue
66
The delicate and fragile _______ _________ _________ forms a soft packing around organs.
areolar connective tissue
67
What is scar tissue formed of?
Connective tissue, which fills in spaces where the original tissue does not regenerate
68
Inflammation is a defense response of which type of tissue?
Connective tissue
69
How does connective tissue function as insulation?
Fat cells or adipose tissue is a connective tissue that insulates organs and provides reserve energy fuel
70
How does connective tissue function as transportation?
Blood is a connective tissue (carries and delivers oxygen and nutrients to tissues)
71
What are connective tissues caracterized by?
Abundant amounts of extracellular matrix in which a variety of cell types are dispersed
72
The extracellular matrix in connective tissue usually includes _______ of one or more types embedded in what?
fibers, amorphous ground substance
73
What are the four classes of connective tissues?
- Blood
- Bone
- Cartilage
- Connective Tissue Proper
74
Differentiate -blast and -cyste cells in connective tissue.
- -blast cells retain their capacity for division and secrete the matrix characteristic to their tissue
- Undifferentiated -blast cells mature and become -cyst cells following matrix production, and are responsible for maintaining the matrix in a healthy state
75
What are the -blast cells in the four types of connective tissue?
- Blood: hemocytoblasts
- Connective Tissue Proper: fibroblasts
- Cartilage: chondroblasts
- Bone: osteoblasts
76
What are the two categories of cells in connective tissue?
1. The cells that secrete the matrix or maintain it (-blast, -cyste cells)
2. The accessory cells which are supported by the connective tissue
77
Give examples of accessory connective tissue cells?
- Fat storing cells
| - White blood cells, mast cells, macrophages, antibody-producing plasma cells
78
What is the extracellular matrix composed of?
Fibers and ground substance
79
What are the three types of fibers?
- Collagen
- Elastic
- Reticular
80
Which fibers are white, extremely tough, and provide high tensile strength?
Collagen fibers
81
Which fibers can be stretched, but recoil to their original length once released?
Elastic fibers
82
Where are elastic fibers found?
Where great elasticity is needed (lungs, blood vessel walls)
83
What are reticular fibers?
- Fine collagenous fibers, which form a delicate branching network
- Support soft organs, such as the liver and spleen
84
What is the ground substance also called? What is it?
- Extracellular matrix
| - Amorphous substance that fills the space between cells and contains fibers
85
What is the extracellular matrix composed of?
- Interstitial fluid
- Cell adhesion proteins
- Proteoglycans
86
What do cell adhesion proteins allow?
The connective tissue cells to attach themselves to matrix elements
87
What are proteoglycans? How do they vary?
- Proteins to which polysaccharides are attached
- Polysaccharides can trap more or less water depending on their nature and form a substance that varies from a fluid to a semi-stiff hydrated gel
88
What are the functions of the extracellular matrix?
Supports cells, binds them together, and functions as a medium through which nutrients and other dissolved substances can diffuse between capillaries and cells
89
What are the three types of loose connective tissue proper?
Areolar, reticular, adipose
90
What are the three types of dense connective tissue proper?
Regular, elastic, irregular
91
What are the three types of cartilage?
Hyaline, elastic, fibrocartilage
92
What are the two types of bone?
Compact and spongy
93
Are the cells of muscle tissue close to each other or far away?
Close together (little extracellular matrix)
94
What are the four histological characteristics common to all muscle tissues?
1. Made of many cells close together
2. Well vascularized
3. Elongated
4. Contain myofilaments
95
Muscle striations are __________ to the axis of the cell.
perpendicular
96
Describe skeletal muscle cells.
- Long
- Cylindrical
- Striated
- Multinucleated
97
Where are the nuclei of skeletal muscle cells located?
On the periphery of the cells
98
How are bundles of skeletal muscle cells tied together and anchored?
Tied together by connective tissue and anchored at both ends by tendons to bones
99
What do skeletal muscles attach to?
- The bony skeleton
| - Facial muscles attach to the skin
100
What kind of tissue has an important role in maintaining a constant body temperature?
Skeletal muscles because they generate heat when they contract
101
Which cells are long and cylindrical with ends that are split longitudinally into a small number of branches?
Cardiac muscle cells
102
Where are the nuclei of cardiac muscles located? How many are there?
One or two nuclei present at the center of the cell
103
Are skeletal muscle cells longer or shorter than cardiac muscle cells?
Longer
104
Describe cardiac muscle cells.
- Elongated
- Branched
- Striated
105
Where do cardiac cells fit tightly together?
At dark-staining junctions called intercalated discs
106
Where are intercalated discs found? What do they contain?
- ONLY in cardiac muscle tissue
| - Contain anchoring desmosomes and gap junctions
107
Which cells are spindle-shaped?
Smooth muscle cells
108
How many nuclei do smooth muscles possess? Where are they located? What shape is it?
One nucleus in the center of the cell that is oval in shape
109
Which muscle cell does not possess striations?
Smooth muscle cells
110
Which muscle cells are found in the walls of hollow organs, such as digestive and urinary tract organs, blood vessels, and the uterus?
Smooth muscles
111
What is the function of smooth muscles?
Propel (squeeze) substances through hollow organs by alternating contraction and relaxation
112
Are nervous cells close to each other or far away?
Close, there is little extracellular matrix between cells
113
What are the two histological characteristics of nervous tissue?
1) There is little extracellular matrix between cells
| 2) Most of the cells are strongly branching
114
What are the two main groups of nervous cells?
- Neurons
| - Glial cells
115
What are neurons made of?
- Cell body (nuclei + organelles)
| - Cytoplasmic ramifications (dendrites + axon)
116
Differentiate dendrite and axon.
- Dendrite: receive stimuli
| - Axon: generates nerve impulses and transmit them from one part of the body to another
117
What is the major function of glial cells?
Support, protect, and bind neurons
118
Where do you find nervous tissue?
- Brain
- Spinal cord
- Nerves and their associated ganglia
119
Which cells are involved in wound healing?
Fibroblasts
120
What are glycosaminoglycans?
Major component of joint cartilage, joint fluid, and other soft connective tissue
121
Differentiate loose connective tissue and dense connective tissue.
Dense connective tissue has a lot of collagen fibers.
122
Which tissue is avascular?
Epithelial
123
Describe the various layers of the stomach.
- Mucosa: Epithelial (simple columnar) with villi
- Submucosa: connective tissue layer
- Muscularis: muscle
- Connective tissue
- Serosa
124
What are the three layers to the muscularis of the stomach? Why do you need three?
- Oblique, circular, longitudinal
| - For grinding and peristalsis of the food
125
What do parietal cells produce?
Hydrochloric acid
126
Where are ciliated columnar epithelium found?
- Upper respiratory tract
- Fallopian tubes
- Uterus
- Trachea
127
What epithelium covers the Bowman's capsule?
Simple squamous
128
What type of epithelium lines an artery and a vein?
Simple squamous
129
In a histological slide of a kidney, what would you see in the cortex and the medulla?
- Cortex: Bowman's capsule
| - Medulla: tubules
130
Where do you find non-keratinized stratified squamous epithelium?
- Inside of your cheek
- Lining of the vagina
- Areas of frequent wear and tear
131
What are the crypts of Lieberkuhn?
Glands which secrete various enzymes
132
Which tissue is located in air sacs of lungs and blood vessels? What's the function?
- Simple squamous
| - Lubrication
133
Which tissue is located in the bladder? What's the function?
- Transitional
| - Stretch, protection against seepage
134
Which tissue is located in the stomach, intestines, and uterus? What's the function?
- Simple columnar
| - Protective, secrete mucus
135
Which tissue is located in the skin and mouth? What's the function?
- Stratified squamous
| - Lubrication, protection
136
Which tissue is located in the trachea, fallopian tubes? What's the function?
- Pseudostratified columnar
| - Movement
137
Which tissue is located in the ovaries, kidneys, thyroid glands? What's the function?
- Simple cuboidal
| - Secretion and absorption
138
Which tissue is located in the vas deferens, male urethra? What's the function?
- Stratified columnar
| - Support and some movement
139
Which tissue is located in mammary and sweat glands? What's the function?
- Stratified cuboidal
| - Secretion, absorption, protection
140
Provide examples of exocrine and endocrine glands.
- Exocrine: salivary or sweat ducts
| - Endocrine: pineal, pituitary
141
What is an apocrine gland? Provide examples.
- Product pinches off and is released from apex
| - Mammary glands, hair follicle sweat glands, goblet cells
142
What is an holocrine gland? Provide examples.
- Product collects in the cell, then when it is released, the plasma membrane ruptures
- Sebaceous glands
143
What is a merocrine (or eccrine) gland?
- Secrete product through plasma membrane (most common type)
| - Salivary, gastric, sweat glands
144
Which exocrine gland is the most common?
Merocrine (or eccrine)
145
Where are hair follicle sweat glands located?
- At the junction of the dermis and subcutaneous fat, from which a straight portion inserts and secretes into the hair follicle
- Odorless, oily opaque secretion that gains its characteristic odor upon bacterial decomposition
146
The secretory parts of the sudoriferous (sweat) gland is lined with what epithelium? What about the ducts?
- Secretory: simple cuboidal
| - Duct: stratified cuboidal
147
Where is loose areolar connective tissue proper found?
- Fascia
- Fat
- Protection and insulation
148
Where is dense regular connective tissue proper found?
- Tendons
- Ligaments
- Flexible but strong
149
Where is dense irregular connective tissue found?
Symphysis pubis joint
150
Which cartilage is found in the ear and epiglottis?
Elastic
151
Which cartilage is found in the trachea ring, joint surface of the bone, larynx, ventral end of ribs, and bronchi?
Hyaline
152
Which cartilage is found in the symphysis pubis joint?
Fibrocartilage
153
Where are reticular fibers found?
Special type of collagen fibers found in spleen and lymph nodes
154
Which connective tissue surrounds blood vessels?
Loose connective tissue proper
155
What is the extracellular matrix of cartilage composed of?
- Collagen
- Abundant ground substance, rich in proteoglycan
- Elastin fibers
156
Which is the only cell present in cartilage?
Chondrocyte
157
What is a Lacunae house cell?
Small space containing a chondrocyte in cartilage or an osteocyte in bone
158
How does cartilage differ from other connective tissue?
- Avascular
| - Cartilage grows and repairs more slowly since it has no direct blood supply
159
How are mature chondrocytes created?
-
Chondroblasts secrete matrix and fibers, and become trapped inside it
- Mature into cells called chondrocytes
160
Which cartilage has shock-absorbing qualities?
Fibrocartilage
161
What occurs at the epiphyseal line? Which cartilage is at the top?
- Growth of a bone
| - Hyaline cartilage
162
Where is compact bone found? Where is spongy bone found?
- Compact bone: lining, hard shell
| - Spongy: network of hard beams of bone tissue inside many bones
163
What is formed at the center of an osteon? What are the circles around called?
- Havarsian canal
| - Lamellae
164
Which structures house the osteocytes in an osteon?
Lacunae (dark lines)
165
How are nutrients brought into an osteon?
Canaliculi (microscopic lines)
166
What is the Haversian canal?
Blood, nerve and connective tissue supply
167
What is the composition of whole blood?
- Plasma (55%)
| - Formed elements (red blood cells, white blood cells, platelets)
168
How do you differentiate erythrocytes and leukocytes under a microscope?
- Red blood cells are enucleated
| - White blood cells are nucleated (purple nucleus)
169
Why do you see a white zone in the middle of a erythrocyte?
Because they are bi-concave
170
What are the functions of blood?
- Transportation
- Regulation of body temperature
- Regulation of body pH
- White blood cells destroy bacteria
171
How is circulating blood tissue formed?
Formed in the red bone marrow by a process called hematopoiesis
172
Which connective tissue is found under skin and in muscle? What's the function?
- Loose CT proper
| - Nourishment, stretch
173
Which connective tissue is found in the ears, nose, and bone ends? What's the function?
- Cartilage
| - Cushion, support
174
Which connective tissue is found in ligaments and tendons? What's the function?
- Dense CT proper
| - Pulling/pushing forces
175
Which muscle is striated voluntary and multinucleated?
Skeletal muscle
176
Which muscle is striated involuntary with branching cells with intercalated discs?
Cardiac muscle
177
Which muscle is nonstriated involuntary, elongated, fusiform shaped cells with a single nucleus?
Smooth muscle
178
How are intercalated discs formed?
By meeting of plasma membranes of two cells
179
What will you see in the cross-section of smooth muscle?
- Only the nucleus
| - Not the spindle-shaped form
180
How do you differentiate an artery and a vein?
Arteries have thicker walls of smooth muscle
181
What muscle lines arteries and veins? Why?
- Smooth muscle
| - Vasoconstriction and vasodilatation
182
What do you see in a transverse cut of skeletal muscle?
- Can't see striations
| - See that nuclei are sitting at the periphery
183
What are specialized characteristics of nervous tissue?
- Excitability
| - Conductivity
184
What is myelin?
Substance rich in lipids (fatty substances) and proteins that forms layers around the nerve fibers and acts as insulation
185
What will you find in the white matter of a cross-section of spinal cord?
- White matter: glial cells
| - Grey matter: neurons
186
What kind of epithelium is the serosa composed of?
Simple squamous
187
What is elastic cartilage made predominantly of? Where is it found?
- Elastic fibers
| - Epiglottis and outer ear
188
What is hyaline cartilage made predominantly of? Where is it found?
- Collagen fibers
- Around bone and joint surfaces
- Functions to reduce friction between bones and absorb shock forces
