Histology Flashcards
(237 cards)
1
Q
What is a tissue
A
An aggregate of cells organised to perform a specific function through a distinctive pattern of organisation
2
Q
4 major types of human tissues
A
Epithelium
Connective tissue
Muscle tissue
Nerve tissue
3
Q
Epithelium functions
A
Protection, detection, sensation, regeneration, absorption, material transport, gas exchange, excretion
4
Q
Body surfaces not covered by epithelium
A
Teeth, anterior of iris, articular cartilage
5
Q
Epithelium structure
A
Sheets of lightly bound contiguous cells with free surface
6
Q
What is the nutrient and oxygen supply for the endothelium
A
Underlying tissue through basement membrane
7
Q
What is the basement membrane made up of
A
Basal lamina + connective tissue
8
Q
Types of epithelial cell shape
A
Squamous, cuboidal, colomnar
9
Q
Colomnar cell shape
A
Elongated
10
Q
Cuboidal cell shape
A
Rectangular
11
Q
Squamous cell shape
A
Flattened
12
Q
Simple endothelium
A
1 layer thick
13
Q
Stratified endothelium
A
Multiple layers
14
Q
Where is transitional epithelium found
A
Lower urinary tract
15
Q
Specialised morphological characteristic of urothelium
A
Domed apical surface of cells
16
Q
Why is the apical surface of urothelium cells domed
A
Allows bladder to distend
17
Q
Why does pseudostratified epithelium appear stratified
A
Nuclei located at different heights
18
Q
Where is endothelium found
A
Lining blood vessels
19
Q
Where is cardiothelium found
A
Lining ventricles and atria
20
Q
Where is mesothelium found
A
Lining body cavities
21
Q
What are Epithelioid cells
A
Closely packed epithelial cells with no apical surface
22
Q
Where are epithelioid cells found
A
Testis, ovaries, islets of langerhans
23
Q
What is the apical domain exposed to
A
Lumen or external environment
24
Q
What is they lateral domain exposed to
A
Adjacent epithelial cells
By cell adhesion molecules and junctional complexes
25
What’s is the basal domain exposed to
Basal membrane
26
Types of lateral domain
Tight junction
Anchoring junction
Gap junction
27
Anchoring junction purpose
Structural support of adjacent cells
28
Gap junction purpose
Create communication contacts between adjacent cells
29
Tight junction purpose
Seal adjacent cells together
30
What are microvilli
Finger like projections on apical surface with passive motility
31
What are stereocilia
Long immobile microvilli
32
Where are stereocillia
Inner ear and epididymis
33
How are stereocilia supported
Actin filaments cross linked by fibrin
34
What are cilia
Hair like extensions from the apical plasma membrane
35
How are cilia supported
Microtubules
36
3 types of cilia
Motile cilia
Primary cilia
Nodal cilia
37
Where are nodal cilia found
Embryos
38
2 main proteins of the ECM
Laminin
| Fibronectin
39
What protein does laminin and fibronectin associate with to organise the basement membrane
Collagen
40
Components of the basement membrane
Basal lamina
| Reticular lamina
41
Basal lamina
Sheet like ecm in direct contact with epithelial cells
42
Reticular lamina
Supports basal lamina and is in contact with connective tissue
43
Basement membrane function
```
Structural attachment
Filtration
Compartmentalisation
Tissue scaffolding in regeneration
Regulation
Signalling
```
44
Function of basement membrane in kidney
Important component of glomerula filtration barrier
45
Role of basement membrane in muscle contraction
Contributes to maintaining integrity of skeletal muscle fibre
46
What does disruption to the basal lamina - muscle cell relationship cause
Muscular dystrophy
47
What are glands made of
Epithelial tissue
48
Where do glands originate from
Invaginated epithelial cells
49
What is parenchyma
Tissue that carries out their function of the organ
50
Do glands produce products intracellularly or extracellularly
Intracellularly
51
What’s is a tubular gland
Glands whose glandular cells form straight or coiled tubes
52
What is an alveolar gland
Glands whose glandular cells form sack like pockets
53
What is a branched gland
A gland where several secretory areas share a duct
54
What is a gland with tubular and alveolar cells called
Tubuloalveolar
55
What is a compound gland
A gland with multiple branches
56
What is an exocrine gland
Products secreted directly to surface or through epithelial ducts
57
What is an endocrine gland
Product secreted into connective tissue and travels to bloodstream
58
Merocrine/eccrine secretion
Products delivered through exocytosis
59
Apocrine secretion
Product secreted through partial loss of cell apical portion
60
Holocrine secretion
Product secreted through apoptosis
61
3 mechanisms of exocrine secretion
Merocrine/eccrine
Apocrine
Holocrine
62
Unicellular gland
Secretion by single cell
63
Multicellular gland
More than 1 cell
64
2 types of exocrine glands
Unicellular
| Multicellular
65
Epithelium purposes
```
Boundaries
Protection
Secretion
Absorption
Filtration
```
66
Epithelium location
Skin surface
| Lining of hollow organs
67
Epithelial tissue characteristics
```
Polarity
Intracellularly Junctions
Regeneration
Metaplastic ability
Avascular
Innervated
Supported by connective tissue
```
68
How is epithelial tissue supported
Connective tissue
69
Types of epithelium
Lining
| Glandular
70
Simple epithelial
Single layer of epithelial cells
71
Squamous epithelial
Flattened cells
72
Simple squamous use
Diffusion
| Filtration
73
Simple squamous location
Alveoli
Endothelium
Mesothelium
74
Cuboidal
Square
| Large spherical nuclei
75
Cuboidal uses
Secretion
| Absorption
76
Simple cuboidal location
Ducts
Kidney tubules
Secretory portion of small glands
77
Columnar epithelium
Tall cells
Oval to round nuclei
May contain goblet cells
78
Columnar epithelium uses
Mucous/enzyme secretion
| Mucous/enzyme absorption
79
Enterocytes
Individual simple columnar cells
80
Non ciliated simple cuboidal location
Intestines
Gall bladder
Excretory glands
81
Ciliated simple cuboidal epithelial location
Small bronchi
| Uterine tubes
82
Pseudostratified columnar epithelium
Cells at different heights but still resting on basement membrane
83
Pseudostratefies epithelium uses
Secretion of mucous
| Movement of mucous
84
What does epithelial tissue rest on
Basement membrane
85
Ciliated pseudostratified columnar location
Bronchus
| Trachea
86
Non ciliated pseudostratified columnar epithelium location
Sperm ducts
| Ducts of large glands
87
Stratified squamous uses
Protect areas prone to abrasiom
88
Keratinised stratified squamous
Surface cell layers dead and full of keratin
89
How do keratinised cells show on photomicrograph
Darker
90
Keratinised stratified squamous location
Epidermis
91
Non keratinised stratified squamous location
Cervix
Rectum
Oesophagus
Mouth
92
Stratified cuboidal and stratified columnar uses
Line ducts of large glands
93
Stratified cuboidal epithelium location
Sweat glands
| Mammary glands
94
Stratified columnar epithelial location
Large glands
Male urethra
Pharynx
95
Other name for Transitional epithelium
Urothelium
96
Transitional epithelium location
Urinary tract
97
Transitional epithelium composition
Basal cuboidal and columnar
| Apical squamous
98
Transitional epithelium characteristics
Impermeable to salts and water
| Distension
99
How does transitional epithelium distend
Plaques at luminal surface allow stretching
100
What shape are luminal cells in the transitional epithelium
Domed when relaxed
101
Exocrine glandular epithelium
Secrete substances onto the surface of the epithelium usually via ducts
102
Goblet cells
Unicellular glands secreting mucin glycoprotein
103
How can goblet cells be stained
Periodic acid Schiff reaction
104
Does H and E stain work for goblet cells
No
105
Exocrine gland characteristics
Glandular portions
| Duct portions
106
Simple exocrine glands
Single duct
107
Complex exocrine glands
2+ ducts
108
Glandular portion shapes
Tubular
| Alveolar
109
Endocrine glands
Secrete into tissues/blood vessels
| No ducts
110
Which type of glands are highly vascularised
Endocrine
111
Compound ducts
Duct branches
112
Mucosa
Epithelium + underlying connective tissue and smooth muscle
113
Mucosa components
Epithelium
Lamina propria
Muscular mucosa
Submucosa
114
What is the lamina propria made up of
Connective tissue
115
What is the muscular mucosa made of
Smooth muscle
116
What is the submucosa made of
Connective tissue
117
Where is the mucosa found
Lining internal organs
118
Other name for mucous membrane
Mucosa
119
Other name for serous membrane
Serosa
120
Serosa components
Mesothelium
| Connective tissue
121
Difference between mucosa and serosa
Mucosa contains smooth muscle layer
122
Layers of mesothelium
Visceral
| Pleural
123
Connective tissue function
Support
Protection
Binds tissues together
124
Types of support provided by connective tissue
Structural
Metabolic
Defensive
125
Precursor for connective tissues
Mesenchymal cells
126
Fibroblast shape
Elongated due to elongated nuclei
127
Fibroblast photomicrograph appearance
Blue
128
Fibroblast purpose
Makes ECM
129
What is ECM made up of
Collagen fibres
Elastin fibres
Ground substance
Glycoproteins
130
What is ground substance made up of
GAGs
| Proteoglycans
131
Collagen photomicrograph appearance
Very lightly stained
132
What are fibrocollagenous connective tissues characterised by
Collagen fibre quantity, type, organisation
133
Loose connective tissue characteristics
Few randomly organised col 1 fibres
Some col 3
Some elastin
134
Loose connective tissue use
Wrap + cushion organs
| Inflammation
135
Loose connective tissue location
Under epithelia
Lamina propria
Surrounds capillaries
Submucosa
136
Dense irregular connective tissue characteristics
Lots of col 1 in many directions
137
Dense irregular connective tissue uses
Structural strength
| Withstands tension in many direction
138
Dense irregular connective tissue location
Fibrous capsules of organs
Fibrous capsules of joints
Skin dermis
Submucosa
139
Dense regular connective tissue characteristics
```
Lots col 1 in 1 direction
Parallel fibres
Few elastic fibres
Withstand great force from 1 direction
Cells in periphery
```
140
Dense regular connective tissue location
Tendons
Ligaments
Aponeurosis
141
Reticular fibrocollagenous
Fine mesh of col 3
142
Reticular fibrocollagenous use
Forms soft internal skeleton to support cells
143
Reticular fibrocollagenous location
Lymphoid organs
144
What cells are in the ECM in fibrocollagenous tissues
```
Fibroblasts
Adipocytes
Macrophages
Neutrophils
Eosinophils
Lymphocytes
Plasma cells
```
145
What are supported by col 3
Highly cellular organs
146
Adipose tissue
High density adipocytes
147
Types of adipose tissue
White
| Brown
148
White adipose tissue characteristics
Unilocular
Widely distributed
Sparse ECM
149
White adipose tissue use
Energy storage in adults
Insulation
Shock absorption
150
White adipose tissue location
Breasts
Hypodermics
Around kidneys
151
Brown adipose tissue characteristics
Multilocular
Multiple fat droplets in each cell
Round central nuclei
Fibrocollagenous septa
152
Brown adipose tissue use
Heat production in newborns
153
Brown adipose tissue fibrocollagenous septa use
Separates brown adipose into lobules
Carry blood vessels
Carry nerves
154
Brown adipose tissue location
Babies
155
Why do babies have brown adipose tissue
Can’t shiver
156
Unilocular
Nuclei pushed to side of adipocytes by fat droplet
157
Cartilage use
Structural support
| Bone precursor
158
What maintains cartilage
Chondrocytes
159
What cells make chondrocytes
Chondroblasts
160
Cells in cartilage
Chondrocytes
161
Chondroblast use
Produce and deposit col 2
162
Chondrocytes location in cartilage
Lacunae
163
Cartilage ECM characteristics
```
Abundant
Rich in GAGs
Rich in hylauronic acid
Fine col 2 fibre lattice
80% water
```
164
Why are h2o and positive ions attracted to cartilage
Negatively charged proteoglycans and GAGs
165
What cells produce ECM in cartilage
Chondroblasts
166
Hyaline cartilage characteristics
Amorphous
| Firm
167
What is a chondrocyte
Chondroblast in lacunae
168
Hyaline cartilage location
Most of embryonic skeleton
Trachea
Epiphyseal growth plate
Articular cartilage in joints
169
What is the most common cartilage type
Hyaline cartilage
170
What is the difference between hyaline and elastin cartilage
Elastin cartilage has more elastic fibres
| Elastin cartilage is more flexible
171
Elastin cartilage location
Ear
| Epiglottis
172
Fibrocartilage characteristics
Thick collagen fibres
Mainly col 1 and 2
Less firm than other types
173
Fibrocartilage use
Tensile strength
| Shock absorber
174
Fibrocartilage location
Invertebral discs
| Pubic symphysis
175
Perichindrium
Specialised layer of highly vascularised fibrocollagenous tissue
176
Perichondrium locatiom
Surrounds cartilage
177
Perichondrium use
Nourishes chondrocytes
| Nutrients diffuse from perichondrium capillaries to cartilage
178
Where does cartilage get nutrients from
Surrounding perichondrium
179
Hypertrophy
Increase in muscle fibre size
180
Hyperplasia
Increase in muscle fibre number
181
Types of muscle tissue
Skeletal
Smooth
Cardiac
182
Where is muscle tissue derived from
Mesoderm
183
Muscle composition
Actin filaments
Myosin filaments
Basement membrane
184
Muscle photomicrograph appearance
Pink stained
185
Connective tissue ecm appearance
Light staining
186
Skeletal muscle use
Voluntary movement
187
Skeletal muscle location
Attached to bones/skin
188
Skeletal muscle characteristics
Long
Cylindrical
Multinucleate
Striated
189
Endomysium
Supporting reticular fibre network around basement membrane of skeletal msucle
190
Perimysium
Thick connective tissue around fascicles
191
Fascicles
Bundles Muscle fibres organised into
192
Epimysium
Sheath of dense connective tissue organising fascicles into whole muscles
193
Satellite cells
Stem cells that can add fibre aiding growth/ after damage
194
Sarcomere
Contractile unit of muscle
195
Myofibrils
Made up of sarcomeres
| Run longitudinally
196
Sarcomere components
```
Z lines
M lines
A bands
I bands
H bands
```
197
Z line
Actin filaments anchored
198
What defines the limit of a sarcomere
Z line
199
How many z lines in a sarcomere
2
200
M line
Myosin filaments anchored
201
How many m lines per sarcomere
1
202
A bands
Myosin filament band
203
What are the darker bands of a sarcomere
A band
204
I band
Actin doesn’t overlap with myosin
205
What is the lighter band of a sarcomere
I band
206
H band
Myosin filaments only
207
Cardiac muscle characteristics
```
Branching
Striated
Uninucleate
Central nuclei that connect at intercalated discs
No satellite cells
```
208
Where do cardiac muscle nuclei connect
Intercalated discs
209
Cardiac muscle function
Propels blood into circulation
210
Why is cardiac muscle damage permanent
Cardiac myocytes cannot divide
| No satellite cells in cardiac muscle
211
Intercalated discs
Communication cardiomyocytes
212
What allows synchronised contraction of cardiac myocytes
Ion transfer in intercalated discs
213
Smooth muscle characteristics
Elongated spindle shaped cells
Central nuclei
No striations
214
Smooth muscle function
Involuntary control
215
Smooth muscle location
Mostly hollow organ walls
| Blood vessels
216
Why does smooth muscle not shorten
Contraction not dependent on sliding filaments
217
How does smooth muscle cytoplasm stain
Dark
218
Contractile cells types
Myocytes
Myoepithelial cells
Myofibroblasts
Pericytes
219
Myoepithelial cells
Surround secretory portion of exo glands
220
Myofibroblasts
Secrete collagen to produce fibrocollagenous scars
221
Pericytes
Proliferate after injury -> become stem cells -> differentiate into fibroblasts
222
Neurone cell body and first part of dendrite
A
223
What cells surround neurones
Glial cells
224
CNS glial cells
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
225
Astrocyte characteristics
Highly branched
226
Astrocyte uses
CNS Enviro regulation
Blood brain barrier
Synapse Insulation
Proliferate around injury to form glial scar
227
Oligodendrocyte use
Myelin production
| Wrap membrane around axon
228
What type of brain/spinal matter are oligodendrocytes common in
White matter
229
Microglia characteristics
Specialised macrophage
Smallest glial cell
Hard to identify
230
Microglia use
Removed damaged cells and debris at injury site
231
Ependymal cell characteristics
Ciliated cuboidal epithelium
232
Ependymal use
Line brain ventricles
| Form part of choroid process that produce CSF
233
PNS glial cells
Satellite cells
| Schwann cells
234
Schwann cell uses
Forms myelin sheath
| Envelope forming unmyelinated axons
235
Schwann cell electromicrograph appearance
Very dark staining
236
How many axons can a Schwann cell myelinate
1
237
How can you tell tendons from ligaments
Tendons denser and regularly arranged
| Ligaments have more elastic fibres and are wavy
