Histology Flashcards
(154 cards)
1
Q
What is this slide stained with? What stains blue with this stain?
A
Alcian blue
- GAG rich structures
- Mucous
- Mast cells
- Cartilage
2
Q
What is this slide stain with?
What stains pink with this stain?
A
Eosin
- Colloidal proteins
- Plasma
Eosinophilic = Acidophilic
3
Q
What is this slide stained with?
What stains black with this stain?
A
Iron haematoxylin
- Nuclei
- Elastic fibres
4
Q
What is this slide stained with?
What stains magenta with this stain?
A
- Hexose sugars
- Goblet cell mucins
- Cartilage matrixs
- Glycogen
- Basement membranes
- Brush border
5
Q
What is this slide stained with?
What stains:
- Purple
- Red/pink
- Pale blue
- Dark blue
A
Purple = chromatin/nuceli and netrophil granules
Red/pink = Erythrocytes/eosin granules
Pale blue = Lymphocyte/monocyte plasma
Dark blue/purple = Basophil granules
6
Q
What is this stained with?
What stains:
Dark blue
Pale blue
Bright purple
A
Toludine blue
Dark blue = nuclei/ribosomes
Pale blue = cytoplasm
Bright purple = cartliage/matrix/mast cell and GAG rich
7
Q
What is this slide stained with?
What stains:
Pink Red
Yellow/Olive green
Dark brown
A
Van giesons trichrome with haemotoxylin counter stain
Pink red = collagen
Cell cytoplasm = yellow/olive green
Nuclei = black
Elastic tissue = dark brown
8
Q
What is this slide stained with?
What stains blue with this stain?
A
Haemotoxylin
- Nuclei
- RNA
9
Q
What is this slide stained with?
A
Silver stain
10
Q
Describe neurones?
A
Neurones are large
25-60 microns
Because of the thickness of slides cannot see all processes
1 to 5 dentritic processes
11
Q
Where is the epithelium from?
What type of epithelium is it and describe it?
A
From the gall bladder
Simple columnar
- Height > width
- Oval nucelus
- Longer axis perpendicular to base of the cell
- Often microvilli or cilia at the apical membrane
- GUT ENTEROCYTES and RESPIRATORY TRACT
12
Q
What type of epithelium is this?
Describe?
A
Intestinal epithelium
- Enterocytes with goblet cells
- Epithelia sit on BM permeability barrier between epithelium and connective tissue
- Microvilli at the apical surface (brush border)
- Brush border increases surface area
- Small intestine = simple columnar
Larger intestine > goblet cells
13
Q
What is this a slide of?
What stain has been used?
A
Microvilli/intestinal
Stained with PAS and haematoxylin
- Microvilli with carbohydrate rich glcocaylx
- Goblet cells and basement membrane rich in hexose
- The stain is magenta
14
Q
What type of epithelium is this?
A
Cuboidal epithelium
- Square
- Round nucleus
- Ducts at exocrine glands: sweat glands, salivary, pancreas and kidney tissue
15
Q
What type of epithelium is this?
A
Squamous (serosa at outer wall of intestine)
- Outer surface of most thoracic and abdominal organs
- Simple squamous epthielum = serosa
- Also lines pleura and peritoneal cavities
- Air sacs of lungs
- Flattened
- Cylindrical ellpitical nuclei at the base
16
Q
What type of epthielium is this where is it founf?
A
Stratified squamous non keratinsing epithlium (left is mouth)
Found in:
- Mouth
- Throat
- Oesophagus
- Anus
- Vagina
17
Q
What type of epthielium is this?
Where is it found
A
Keratinised stratified squamous epithelium
- Epidermis
- Lower layers are similar to stratified squamous
- Upper layers synthesise a unique collection of proteins - interact with cytoskeleton of cell to produce keratin
- Keratin: a dense protein that fills the cytoplasms of cells = tough and waterproof
- When the cell is full of keratin they die and are sloughed off
Left = Hairless skin at lower lip
pink = dead keratinised squames
Boundary later with blue keratohyaline granules STRATUM GRANULOSUM
18
Q
What type of epthlium is this?
Where is it found?
A
Pseudostratified
Multilayered but stretches when flattened
Slide = trachea
Also found in urinary tract
19
Q
What is this slide showing?
A
Caridiac muscle (myocardium)
- Branching chains of cardiac myocytes (15 x 100 microns)
- Striations (myofibrils and repeat sarcolemmas)
- Dark intercalated disks
20
Q
How does cardiac muscle differ from skeletal?
A
Structurally
- Branched mononuclear with no stem cells
Phyisologically
- Contract and relax without rest, secrete hormones (ANP when stretech excessively, increases water/Na+/K+ excretion and inhibits RAAS)
21
Q
What is this slide showing?
A
Intercalated disk
With desmosomes and adherant junctions (stick)
With gap junctions (electrical coupling)
Disc = Black
Myofibril = Blue/black
MIT/RBC = red
22
Q
What are the functions of the intercalated discs?
A
Desomosomes anchor one cardiac muscle to the next by immediate cytoskeleton filaments
Gap junctions allow ion transfer between cardiac muscle - electrochemical coupling not cardiac conduction!
23
Q
What is this slide showing?
A
Purkinje fibres (with PAS proceedure - magenta)
- Large modified muscles
- Large vacuoles
- Few myofibrils therefore pale H and E
- Stores of glyocogen (PAS)
Cardiac conduction
24
Q
Describe valves?
A
- Thick collagen with occasional elastic tissue
- Both surfaces with endothelial cells
- Chordae tendinae = Fibrous
25
Describe pericardium?
- Single layer of mesothelial cells on the basement membrane with thin loose elastic/ fiberous tissue
26
Describe endocardium?
- Single layer on the heart
- Endothelial cellls are on the basement membrane with thin loose elastic/fiberous tissue
27
What is the slide showing?
Artery = Left
Vein = right
3 layers
1. INTIMA (innermost)
- endothelial cells on loose connective tissue with occasional myo-intimal cells
2. MEDIA (middle)
- smooth muscle, elastic and collagen
3. ADVENTITIA (outermost)
- dense collagen and elastic
28
What is the slide showing?
Muscular artery
- Well defined medial later (smooth muscle in concentric rings)
- Medial layer interspersed with elastic
- Media/intima divide = Wavy internal elastic lamina
- Adventitia = thick strands of collagen/elastic with vasa varsorum and nerves
- Adventitia/media divide = external elastic lamina only in large muscular
29
What is this slide showing?
An artey with plaque and thrombus stained with iron haemotoxylin
30
What is this slide showing?
Elastic artery with mallory's stain
- Elastic = red
- Collagen and muscle = blue
- Medial layer thick with concetric SHEETs of elastic interspersed with smooth muscle
- As vessels enlarge - contain their own blood supply = vasa vasorum
At the top = intima then i.e. vascular endothelial cells on basement membrane
31
What is this slide showing?
Arterioles
- 3 layers of fewer of muscle at the media
- No internal elastic lamina therefore may completely close when the muscles contracts
- Poor adventitia - mainly collagen and elastin
Function: highly responsive to vasoactive stimuli - regulation of peripheral resistace
32
What is this slide showing?
Glandular acinus at the rectal mucosa
- Lined by enterocytes and goblet vells
n. b. mucosa does not ever contain blood vessels
33
What is this slide showing?
Mature adipose with capillaries
34
Describe capillaries?
- Sometimes have contractile pericytes
- Continous or fenestrated
Diameter is the size of an erythrocyte
35
What is this slide showing?
Enodthelial cells (electron micrograph)
- Specialised: released vasoactive substances
- Capillary at the centre - wall = 1 micron
36
Function of endothelial cells?
1. Influence muscle tone
2. Coagulation
3. Produce cell adhesion molecules - influence lymphocyte/neutrophil migration
4. AT of molecules acroos the cytoplasm
37
What is this slide showing?
Venules
- Thin walled
- Pericytes alongside them
- Pericytes become continuous as the vessel gets bigger
- In veins there are no pericytes, replaced by smooth muscle
- Irregular outline
38
What is this slide showing?
Veins, top left x2
- Same layers as arteries but thinner and poor boundaries
- Irregular outline, large lumen and therefore same blood at lower pressure
- Wider lumen than arterioles but slower flow therefore same vol/sec
39
What is this slide showing?
Large veins
- Thick wall
- Distinct intima/media layer
- Medial later with longitudinal smooth muscle
- Adventitia - thick with longitudinally arranged muscle fibres
40
What is this slide showing?
Lymph vessels
41
Describe lymph vessels?
- Pink staining blood plasma and valves
- Small = like cappillaires
- Large = like veins
- Walls = connective tissuse with some muscle
- Less pressure than in venules
- Somtimes lymphocytes
- Transports antigens and activates lymphocytes from tissue to lymph nodes and resident macrophages
- Drains excess fluid from tissue
- No nlood
42
What is this slide showing?
RBCs stained with leshimans stain - a type of romanovsky smears
- 44% of blood
- 4-5 million per microlitre
- Anucleate = leads to biconcavity
- lifespan = 120 days
- 7.5 microns
43
What is this slide showing?
Reticulocytes
- Mature RBCs loose cytoplasm and nucleus
- Reticulocytes = immature RBC with some visible ribosomes, i.e. some dark staining granules
- \<1% of circulating RBCs
- Increased number iwth increased RBC production in blood loss
44
What is this slide showing?
Eosinophils (romanovsky/leishman's)
- 2 to 3 lobed nucleus
- Bright pink granules
- Acidophils
- Circulation for a few hours
- 5% of 1%
- Diurnal = highest in the morning
- Phagocytose antigen/antibody complexes associated with parsitic infection
- Neutralise histamine
45
What is this slide showing?
NEUTROPHILS (leishmans stain)
Polymorphonuclear leukocytes
- Multi lobar nucleus
- Most numerous (40-70% of 1%)
- Phagocytic
- Engulf and destory bacteria
- Leave blood stream to enter tissue at the infection site
46
Describe granulocytes?
Fine granules = Granulocytes
1. Primary - lysosomes, acid hydrolases, antibacterial and digest
2. Secondary - neutrophil specific, regulation of the inflammation response
3. Teritiary - facilitate the insertion of proteins to cell membranes
47
What is this slide showing?
BASOPHILS
- Not multilobar
- Dark blue granules which appear to fill the cell
- Least common 1% of 1%
- Similar role to mast cells
- Secrete histamine and other vasoactive substances - increased blood flow locally
48
What is this slide showing?
LYMPHOCYTES
- Small cells with dark staining nucleus
- 20-50% of 1% (most common non granulocyte)
- B and T indistinguishable
- Immature grow to be bigger than RBC, smaller than granulocytes
- Mature are roughy of equal size to granulocytes
49
What is this slide showing?
MONOCYTE
- Kidney shaped nucleus
- No granules
- Pale blue cytoplasm
- Immature cells with differentiate to various forms when the leave the blood and enter the connective tissue
- Many diff to a macrophage
In the blood and alveolar spaces
50
What is this slide showing?
PLATELETS
- Smaller than a red cell
- Anucleate
- Fragments
- From mutlinuclear megakaryocytes
- Blue
51
4 types of platelet granules?
1. Alpha - clotting
2. Dense
3. Lysosomes
4. Peroxisomes - elimation of oxygen radicals
52
What is this slide showing?
Muscular artery
- Circumferential smooth muscle at the media
- When this contracted reduces the diameter of .vessel
53
What is this slide showing?
Elastic tissue (elastic van giesons with iron haemotoxylin counter stain)
- Elastic tissue is in tube like sheets - elastic lamina
- Elastic = black
- Smooth muscle = mushroom
- Collagen = pink
54
What is this slide showing?
RESPIRATORY EPITHLIUM stained with toludine bone
SIMPLE/PSEUDOSTRATIFIEF COLUMNAR CILIATED EPITHLIUM
- Nuclei and ribosomes = dark blue
- Cytoplasm = blue
- Non ciliated goblet cells
- Underlying tissue rich in BVS and seromucous glands
- Mucous prevents the dehydration of epithelium and traps partical matter
55
What is this slide showing?
NOSE (H&E and Alcian blue)
- Mucous/cartilage = blue
- Central bone plate = pink
- Respiratory epithelium either side
- Thin walled blood vessels between epithlium and bone
- Mucous containing goblet cells stain bright blue
56
What is this slide showing?
NOSE
- Similar cillated respiratory epithelium except at the opening
- Concha covered in respiratory epithelium
- Swell bodies - thin arterioles/venules deep to the epithelium
- Thin skin allows the escape of water moistening air
57
What is this slide showing?
OLFACTORY EPITHELIUM
- Roof of the nose below the cribiform plate
- Pseudo-stratified columnar epithlium with basla and sustenacular (supporting cells)
- Bipolar neurons - dentric processes to surface
- Serous glands to surface( solvent to odourous substances)
- Thicker than respiratory epithelium
Speicialised cells = Bowman's glands - small serous glands below the olfactory epithelium
58
What are sustenacular cells?
Tall narrrow cells in contact with basement membrane of olfactory epithelium
Bulky cytoplasm near lumen
Cytoplasm acculumates yellow/brown pigment
59
What does this slide show?
LARYNX
Respiratory epithelium except at the vocal folds
Vocal folds - stratefied squamous epithelium = more robust to with stand vibration
Below epiglottis larynx = 2 sets of folds
60
Describe the vocal folds?
Vocal folds
- Contain the free upper margin of elastic tissue (conus elasticus)
- Tensioned by voluntary skeletal muscle = vocalis muscle
FALSE FOLDS - upper = resp type
VESTIBULE - between = resp type
TRUE FOLDS = stratified squamous epithelium
61
What is shown on this slide?
TRACHEA
Pseudo-stratified, cilliated, columnar epithlium
62
What is shown on this slide?
VOCAL CORDS
stratified squamous epithelium
63
Where is this slide taken from?
What is the green arrow pointning to?
What is the red arrow pointing to?
Vocal folds
Green arrow pointing to seromucous glands
Red arrow pointing to voluntary skeletal muscle
64
Where is this slide taken from?
What is it showing?
TRACHEA
- n.b. in lower lung may obserbve C shaped rings of cartilage and oesophagus
- Lumen of the trachea = top
- C shaped cartilage = bottom
- Epithelium = pseudostratified columnar epithelium
- Note serous glands visible which secrete to the surface
- With h&e goblet cells stain white
65
Where is this slide taken from?
What is it showing?
BRONCHUS
- Respiratory epithelium
- Held open by hyaline cartilage framework (dark stain) which appear as isolated glands
- Smooth muscle band under epithelium
- Lymph nodules (MALT- mucosa associated lymph tissue) at connective tissue
66
Where is this slide from?
What is this slide showing?
TRACHEA
- Left arrow points to MALT nodule
- Right arrow boinds to smooth muscle band
Lymph node = discrete, encapsulated collection of lymphoid tissue
Malt nodule = no capsule, intimately related to epithelium
67
Where is this slide taken from?
What is it showing?
BRONCHIOLES
- \<1mm
- Simple ciliated respiratory epithelium
- No hyaline cartilage
- Smooth muscle
- Lymph nodes
- Closely associated with arteries and veins
- NO GOBLET CELLS
Unlikely bronchi may be constrictied by smooth muscle as there is no cartilage
68
Where is this slide taken from?
What type of epithelium?
TERMINAL BRONCHIOLE
Simple cuboidal epithelium
69
Describe terminal bronchioles?
- Simple cuboidal epithelium
- Sparsely ciliated
- Clara cells - many large ribosomes, ER, and granules - function is secretory and synthetic
- Sphincter like smooth muscle ring
70
Describe respiratory bronchioles?
- Simple cuboidal epithelium
- Larger than terminal bronchioles = beginning of the respiratory portion of the lung
71
Where is this slide taken from?
What type of epithelium?
ALVEOLI
- Walls = capillaries between SIMPLE SQUAMOUS EPITHELIUM
- Fibroblasts in the walls = Produce type 3 collagen (reticulin) and elastic tissue (recoil)
- 70% of SA \<1mm
- Adjoing alveoli connected by pores = equal inflation
72
Describe type 1 and type 2 pnuemocytes?
TYPE 1 CELLS thin
- Flat cells, flat nuclei 40% population, 90% surface area
TYPE 2 CELLS globular
- Secretes surfactant (lipid rich) 60% population, 10% surface area, rounded, round dark staining nuclei
73
Where is this slide taken from?
What is it showing?
ALVEOLI - ALVEOLAR MACROPHAGES
- Free roam in the alveoli = phagocytose particulate matter and cell debris
- From monocytes in the blood
- Other macrophages stay in the lung substance and engulf material that enters the alveoli wall
- Contains black ingested dust particles (carbon)
ALVEOLAR: enter terminal/resp bronchioles and pass to lymphatics or to be transported to mucocillary escalator
FIXED/SEPTAL: remain in the interstitium between cells and tissue
74
What is this slide showing?
What is:
A
BL
EP and EP1
G
Type 2 pneumocyte
A - alveolus
BL - basement membrane
EP and EP1 - type 1 pnemocyte
G - surfactant containing granules
75
What is this slide showing?
Pulmonary blood vessels
- Large pulmonary blood vessels accompanying bronchi
- Indistinguishable from systemic counterparts EXCEPT large pulmonary arteries which what longitudinally running elastic fibres in walls
- Large pulmonary beins with clearly defiined medial layer of muscle and elastic tissue and well defined
76
Where is this slide from?
What type of epithelium is it?
LIP
Mucosa = typical of the mouth stratified squamous non keratinsing epithlium
At the margin - abrupt transition to skin stratified squamous keratinsing epithlium
Connective tissue - submucosa = collagen and elastin
Deeper layers - glands and striated skeletel muscle (change in the shape of the oral cavity)
Small blood vessels @ submusoa helps to keep moist
77
Where is this slide from?
What type of epithlium is it?
LIP - TRANSITION
Transition from lower stratified squamous non keratinsing epithlium to upper stratefied squamous keratinsing epithlium
78
Where is this slide taken from?
What type of epithelium?
INNER LIP
- stratified squamous non keratinsing epithlium
- Small clumps of salivary tissue
- Sebaceous glands (fordyce's spots) open to surface rather than hair follicles
79
Where is this slide taken from?
Hair follicle from the keratinised surface of the lip
80
Where is this slide taken from?
What type of epithlium is shown?
Tongue
- Stratified squamous non keratinsing epithlium on ventral surface (lower)
- Stratified squamous keratinsing epithlium on dorsal surface (upper) - constant abrasion
Coarse multi directional skeletal muscle bundles
Intrinsic fibres: Skel muscle inserts to the fiberous connective tissue underlying muscosa
Extrinsic fibres: skel muscle inserts into lower jaw
Mixed sero-mucous salivary glands
Lymph nodules - particularly at posterior 1/3 of the tongue
81
Where is this slide taken from?
What type of epithlium?
TONGUE - UPPER SURFACE
- Stratified squamous keratinising epithilium
- Connective tissue
- 2 types of salivary gland
- Large bundles of striated muscle
82
Where is this slide taken from?
TONGUE - SEROUS GLANDS
- More pink staining
- Small serous salivary glands
- Cluster of grapes
- Nucelus on base
83
Where is this slide taken from?
TONGUE - MUCUS GLANDS
- Small salivary mucus glands
- Mucous = pale
84
Where is this slide taken from?
2 Paler staining tastebuds embedded in opposing sides of adjacent fungiform papillae
- Dorsal tongue surface: complex folds = papillae sweet (tip), salty (front/side), sour (further back) bitter (whole back)
85
Describe the three different types of pappilae?
1. FILIFORM PAPILLAE (thread like) - most common, tall, pointed at whole anterior 2/3
2. FUNGIFORM PAPILLAE (mushroom like) - at the top and sides and at the lateral side fungiform papillae = pale single, spindle shaped taste buds with nerve/synaptic vesicles
3. CIRCUMVALLATE PAPILLAE (V-shaped row) at marger anterior 2/3 and posterior 1/3
86
Where is this slide taken from and what is it showing?
PAROTID SALIVARY GLAND (SEROUS ONLY)
- Striated duct (top left)
- Surrounded by serous acini
- Synthesise alpha amylase
- Secreted via ducts to the mouth
- Ducts can alter ionic concentrations
1. Branches of the facial nerve pass through the gland
2. Large lymph nodes embedded within the gland
SECRETORY CELLS
Pyramidal, spherical nucleus, basal cytoplasm full of rER, apex contains prominent secretory granules (pink staining)
DUCT CELLS
Simple cuboidal (stratfied at the distal end)
87
Where is this slide taken from?
What is C ?
What is D?
Parotid gland
C is a nerve
D is a large lymph node
Inset is a close up of a lymph node
Parotid saliva contains IgA (from plasma), combines with proteinous pieces so reaches the intestine unmodified by amylase
Striated duct from invaginations indicative of water reabsorption
88
Where is this slide from?
What is it showing?
SUBLINGUAL SALIVARY GLAND
- Pale staining secretory cells
- Darker staining duct with simple cuboidal epithelium
- Flattened oval nucleus at the base of cells
- Branched tubular acinar glands
- Sticky mucus rich secretion
- Major constituent = polysaccharides
89
Where is this slide taken from?
What is it showing?
SUBLINGUAL GLAND = PSNS GANGLION
Many nerve cell bodies
Involved heavily in secretion regulation
90
What is this slide showing?
SUBMANDIBULAR SALIVARY GLANDS
- Well defined / globular
- Branched tubulo-acinar
- Interspersed with fat adipose
- Mixed secretion - part mucus, part enzyme rich
DEMI LUNES - serous cells form demi lunes at the closed end of tubules
91
What is this slide showing?
Lymph nodule within submandibular gland
92
What is this slide showing?
EPIGLOTTIS
- At posterior of the tongue
- Boundary of oropharynx and laryngeal pharynx
- Mostly stratified squamous non keratinising epithelium
- Lower part is posterior - pseudostratified columnar ciliated epithlium
BOX A = buccal surface - faces mouth
93
What is contained within the epiglottis?
1. Elastic cartilage
2. Lymph nodules
3. Salivary glands
94
What is this slide showing?
EPIGLOTTIS
Stratified squamous non keratinsing epithelium
95
What is X?
A taste bud surrounded by squamous epithelium
96
What is this slide showing?
SUBLINGUAL GLAND
- Mucinous acini
- Basally located nuclei
- Ducted lined by cuboidal/columnar epithlium
Michael Palin = Mucus Pale
97
What is this slide showing?
- Serous glands at the bottom
- Mucus glands at the top
- This is mixed
THEREFORE THIS IS A SUBMANDIBULAR GLAND
98
What is this slide showing?
This is purely serous (granules)
This a a partoid gland
THEREFORE IT CONTAINS BRANCHES OF THE FACIAL NERVE
99
What are the layers of the GI tract?
1. Mucosa - innermost
- 3 comps: epithelium (folded), connective tissue (lamina propria with lymphiod), smooth muscle ring (muscularis mucosa?
2. Submucosa
- Loose connective tissue, glands and lymphoid tissue, many blood vessels, MEISSNER'S PLEXUS (enteric nervous system)
3. External muscle coat (muscularis externa)
- 2 layers of smooth muscle that propel food, between layers = AUERBACHS PLEXUS
4. SEROSA
- Simple squamous epthelium
100
What is this slide showing?
What type of epithelium?
OESOPHAGUS
- Stratefied squamous non keratinising epithelium
- Think lamina propria
- Narrow muscularis mucosa
BELOW DIAPHRAGM
- simple columnar (same as gastric in stomach
- site of pathological change
101
Describe submucosa and muscularis externa of oesophagus?
Sub mucosa: Sero-mucinous glands (lubrication), large thin walled vessels (@ the distal end - oesophageal varicostities)
Muscularis externa:
Upper 1/3 = skeletal
Middle 1/3 = mixed
Lower 1/3 = smooth
102
What are the four regions of the stomach?
Describe the stomach?
STOMACH 4 regions: cardia, fundus, body, pylorus
- Cardia and body histologically similar wit w.r.t glands
- Mucosa folds into rugae
- Simple columnar epithelium punctuated by gastric pits (gastric gland drainage)
- Mucularis externa = 3 layers tihck
- Additional oblique muscle fibres for churning
103
Describe gastric glands?
Tubular at the mucosa
Fill the lamina propria
3 main cell types:
1. Parietal (HCl and intrinsic factor)
2. Chief cells (dig enzymes - pepsin)
3. Mucus neck cells (lubricant and acid resistant mucus)
- Full glands at the body and fundus
- No parietal cells or chief cells at cardia and pylorus
104
Where is this slide from?
What type of epithelium?
STOMACH BODY - GASTRIC MUCOSA
- Simple columnar epithelium produce acid resistant mucin
- Gastric pit invaginations = gree n arroves
- Several tall, straight or branched glands to each pit
- Submucosa = loose connective tissue with abundant vessels
- Muscularis externa = 3 layers of smooth muscle
Muscularis mucosa also contains elastic (black) to stop stomach collapse on emptying
105
Where is this slide from and what is it showing?
PARIETAL (OXYNTIC CELLS)
- A tgastric glands body/fundus
- Upper part of gland close to the pits
- Globular - stain bright pink with H and E
- Cell surface invaginated (intracellular canaliculi)
- Rich in carbonic anyhydrase
106
Where is this slide from and what is it showing?
CHEIF CELLS
- Pyramidal at the deeper gland
- Cytoplasm - blue with H and E - contains granules (pepsinogen/lipases)
- At the body and the fundus
- Close to the muscularis mucosa
PEPSIN = affinity for collagen
107
Where is this slide from and what is it showing?
PYLORIC REGION
- Cardiac and pyloric glands shorter
- Glands collected
- Mainly mucus neck cells
- Scettered with cells producing gastrin
108
What is this slide showing
Gastroduodenal junction
109
Describe the villi and crypts?
Intestinal lining - folds = pilcae circularis (highest in jejun lowest in distal colon)
Further surface area will increase - villi
VILLI: simple columnar epthiul with a short life but are replaced by the crypt population
Villi contain: venule, arteriole, lacteal, smooth muscle
Ventule and lacteal to the liver
CRYPTS OF LIEBERKUHN: between villi and stem population, migrate to the top and are shaved off (5 days)
110
What is this slide showing?
Describe
Enterocytes
- Major absorptive cell
- 300 short microvilli in apical surface - BRUSH BORDER
- Outer surface of brush border = glycocalx filter
- Most nutrients absorbed through this
- Water and glucose absorbed via some intracellular pathways
High concentrations of hexose suhars mean brush border stains intesely with PAS (MAGENTA )
111
Where is this slide from?
Describe?
DUODENUM
- 12 inches, few plicae circularis
- Villi - broad and leave like
- Few goblet cells
- Submucosa contains mucus secreting BRUNNERS GLAND -alkaline secretion neutralises chyme
Brunners gland = bottom right
Few pale stained goblet cells
Long crypts
112
Where is this slide from?
Describe?
DUODENUM
- Crypts form new enterocytes and goblet cells
- Dividing cells have very dark staining nuclei or sets of chromosomes
- At the bottom of crypts = differentiated paneth cells
- Secrete lysozyme - breakdown of bacterial cell walls
- Regulate flora of the gut
- Bright pink cytoplasmic granules
113
Where is this slide taken from?
Describe?
JEJUNUM
- Closesly packed plicae circularis
- MANY goblet cells
- Long narrow villi
- Short crypts
- Loos submucosa
- No bruners gland
- Lymph nodules at lamina propria but do not penetrate submucosa
114
Where is this slide taken from?
Describe?
ILEUM
- Final segement of small intestine therefore fewer plicae and shorter villi
- Goblet cells increase towards the distal end
- Large PEYERS PATCES at submcosa
115
Where is this slide taken from?
ILEUM .
Serosa - simple squamous on the edge of longitudinal muscle highlighted
116
What is this slide showing?
Describe?
VERMIFORM APPENDIX
- From caecum
- Simple columnar
- Goblet cells
- No villi
- Simple crypts
- Lamina propria and submucosa full of lymphoid tissue
- No musuclaris mucosa
- Muscularis externa present
- Transverse smooth muscle at the muscularis extera= taenia colis
- Fat filled
117
What is this slide showing?
Describe
APPENDIX
- Simple columnar
- Rudimentary crypts few goblet cells
- Lamina propria at sub mucosa full of lymphoid tissue
118
What is this slide showing?
Describe
COLON (close packed crypts abundant goblet cells)
- All segements similar histologically
- Little folding
- No villi
- Mucosa contains close packed crypts with abduntant goblet cells and enterocytes
- Restricted lamina propria
- Prominent muscularis muscoa
- Muscularis externa = thickened inner circular later, outer layer drawn into three longitudinal bands TAENIAE COLI
119
What is this slide showing?
RECTO ANAL JUNCTION
- Rectum = similar to colon
- Simple columnar epithelium
- Anal canal = stratified squamous epithelium (keratinised at the end as lip)
120
What is this slide showing?
Box B?
Box D?
RECTO ANAL JUNCTION
- Box B = striated muscle of sphincter
- Box D = anal glands
121
What is this slide showing?
Villous
Submucosa with Brunners glanfs
Duodenal epithelium contains some lymphocytes between epithlium
DUODENUM
122
What is this slide showing?
- All of this fits on a microscopic slide therefore not colon
- Flat mucosa with no villi
- Abundant lymphoid tissue in lamina propria and submucosa
- Lack a muscularis mucosa
- Recieves blood supply from superior mesenteric artery
VERMIFORM APPENDIX
123
What is this slide showing?
- Flat surface
- No villi
- Numerous straight crypts
- Abundant goblet cells
- Prominent muscularis mucosa
- Stem cells at the base of crypts
COLONIC MUCOSA
124
What is this slide showing?
LIVER
- Hepatic portal system recieves nutrients
- Main cells = hepatocytes
- 4 Lobes
- Polygonal lobules of cells
- Each lobule with central vein and radiating hepatocytes
- Between cords = sinusoids bathe hepatocytes in a mix of venous and arterial blood
- Blood drains from each lobule via central vein = hepatic
125
What is this slide showing?
LOBULE
Small muscular arterole = top left
Venule = bottom
Bile ductule = top right
- Cords of hepatocytes
- Sinusoids (wide thin fenestrated capillaries) = 70% portal venous blood, 30% portal arterial blood
- Portal triads at corners of the lobules
- Arteriole (hepatic artery), venule (hepatic portal vein), bile duct
Hepatocytes store: glycogen and tryglycerides
126
What are the main functions of hepatocytes?
1. Creation/store of energy as glycogen and fat
2. Synthesise plasma protiens
3. De-amination of amino acids and production of urea
4. Uptake, synthesis, excretion of bilirubin and bile acids
5. Detox and inactivation of drugs by oxidation, methylation or conjugation
127
Where is this liver from?
What are green arrows pointing to?
Liver
Cords of hepatocytes with paler staining sinusoids between
Nuceli of endothelial sinusoidal cells smaller and darker than that of hepatocytes
- wide thin walled fenestrated capillaries
- endothelial cells interspersed with:
**1. Kupffer cells = fixed macrophages**
**2. ITO cells - perisinuosoidal cells**
- too thin to resolve
- sit on a meshwork of reticulin (collagen 3)
- separated from hepatocyte cords by the SPACE OF DISSE
128
What is this slide showing?
Kupffer cells in the lining of the endothelium
- Phagocytose blood borne pathogens
- Part production of billirubin
Kupffer cells in slide have taken up blue/black ink
Line cords between staining pink hepatocytes
129
What is this slide showing?
Gl?
Mi?
N?
RER?
Hepatocyte ultrastructure
* GI = glycogen
* Mi = mitochondria
* N = nucleus
* RER = rough endoplasmic reticulum
sinusoidal membrane contains transport mechs for pinocytotic release of macromolecules canalicular membrane is target for bile discharge well developed rER - synthesis plasma proteins sER - inactivation of drugs (enzymes) glycogen particle rosettes and lipid droplets present n.b. peripheral hepatocytes are more active and exposed to more glucose first also hepatocytes at centre are depleted of glycogen first
130
What is this slide showing?
GALL BLADDER
- Billary tree = all cuboidal epthelium
- Smaller vessels = simple
- Distal end = Stratified
131
Describe gall bladder epithelium?
- Simple columnar with poor brush border
- Adapted for water reabsorption
- Epithelium (on submucosa) thrown into folds (not villi)
- Gallstones may be present at the lumen
- Large veins in wall (in image)
- Smooth muscle outer surface
- Serosa visible at the top (simple squamous)
n. b gall bladder contracts by CCK
132
What is is this slide showing?
EXOCRINE PANCREAS
Arrows - centroacinar cells
- Exocrine = mass of gland
- Serous (watery/enzyme rich)
- Digestive enzymes are from the same cell, secretion granules at upper part of the cell
- Enzymes released as food enters the duodenum
- Enzymes activated by alkaline enviornment of duodenum
133
What is this slide showing?
PANCREAS
1. Pacinian corpuscle - pressure sensor in the pancreaas
2. Nerve plexus with vagus nerve
Also contains islets of langerhans
134
What is this slide showing?
- Each acinus has a narrow intercalated duct
- IDs connect acinus to main duct
- Larger ducts - 1/2 main duct that enter duodenum with bile duct
SIMPLE CUBOIDAL EPITHELIUM THAT IS STRATIFIED AT THE END
135
What is this slide showing?
Portal triad alternative
136
What are the three types of muscle?
What are the other contractiles?
Smooth - visceral, any body organs and blood vessels
Skeletal - voluntary, mainly attached to bony skeleton, **striated**
Cardiac - only at heart branching/striated
Other contractiles:
1. Pericytes(along some BVs)
2. Myofibroblasts (scar formation)
3. Myoepithelial cells (milk @ lactate)
137
What is the slide showing?
Smooth muscle
- Discrete cells with cell junctions
- Longitudinal - fusiform with cylindrical nuclei
- Transverse - round cell and nucleu
- Central nucleus - no striations
NOT ORGANISED INTO SACROMERES .
- Anchored to cell membrane in clumbs
Electrically coupled via GAP JUNCTIONS
- surface receptors for hormonal stimuli
138
Describe smooth muscle arrangement and gap junctions?
- Each junction = 6 connection proteins
vital for coordinated contraction
Guarded central pore - small mols pass form one cell to the next = electrical coupling
139
Define: Sacromere?
A regular repeat structure within myofibrils = interdigited actin and myosin
140
Define: myofibril?
Small intracellular fibril, sacromeres joined end to end
141
Define: muscle fibre?
Fusion of many myocytes with 100s of myofibrils, surrounded by common plasmalemma
Behaves as a single cell - many nuclei
142
Define: fasiculus?
Bundle of muscle fibres surrounded by connective tissue
143
# Define:
Endomysium
Perimysium
Epimysium
Endomysium - a lace work of connective tissue between muscle fibres
Perimysium - surrounds group of fibres to form a fasciculus
Epimysium - connective tissue around fasciculi to form muscles
144
What is this slide showing?
Muscle fibre and longitudinal skeletal muscle
- Long unbranched
- Many nuclei
- Longitudinally = nuclei at fibre edges
- Transversely = aggregated to fasciculi, nuclei at edge
Left = tongue
EXTRINSIC FIBRES = poke out of mouth
INTRISIC FIBRES = manipulate food
145
What is this slide showing?
Skeletal muscle - transverse
- loosely aggregated to fasiculi by perimysium
- Nuclei at periphery of fibre
- Skeletal muscle individually innervated in motor units
- Mitachondria between muscle fibrils within muscle fibres
May see glycogen and lipid droplets
146
What is this slide showing and what is it stained with?
Sarcomere
Iron haematoxylin
- Unit structure of sacromere
- Z line to Z line
- in contraction shortens by up to 1/3
Myofibrils run parallel with sacromeres in register = STRIATIONS
147
What is contained wit?
I band?
A band?
H band?
I band = actin only
A band = actin and myosin
H band - myosin only (with m line)
SARCOMERES JOINED END TO END AND SIDE TO SIDE AT Z LINE
148
What is this slide showing?
CARDIAC MUSCLE
- Discrete rectangular cells that are joined end to end
- Cental nuclei
- Branching
- Connected by intercalated discs that hold cell in place physically and electrically couple
1. Desmosomes
2. Adherent junctions
3. Gap junctions
Aerobic respiration only many mitachondria, dont have own nerve supply
149
Describe sarcomeres?
When stimulated actin fibres slide within the A band
- Brings the z line closer together
- Shortens the sacromere by up to 30% **extrinsic work**
- Tension increases **intrinsic work**
Structural protein = titin
Upper fibril = contractile
Lower fibril = structural
150
What is this slide showing?
SKELETAL MUSCLE LONGITUDINAL
Slide is from **tongue**
- Each skeletal muscle fibre = hundreds of myoblasts fuse to syncitium
- Each fibre = many nuclei under plasmalemma at side of fibre - DISTINGUISHING PINT .
n. b. small fasicicles usually dneote small motor units = fine control
151
What is this slide showing ?
SKELETAL MUSCLE TRANSVERSE
- polygonal pink fibres
- arranged in clumps **fasicicles**
NOTE note all skeletal muscle is attached to bone - when skeletal musvle are attached together by fibrous connective tissue = raphe
152
What is this slide showing?
SKELETAL MUSCLE BANDING - IRON HAEMATOXYLIN
- I band = pale, predominantly actin
- Z line = at the centre of I band
- A band = darker staining = MYOSIN RICH
A band is not actin
@ the centre of each A band = paler H band with M line
I stands for **isotropic**
A stands for **anisotropic**
153
What is this slide showing?
FIBRE ARRANGEMENT LONGITUDINAL •
Striations (myofibrils and repeat sarcolemmas)
Dark = A band
Light = I band
Z lines connected
IN REGISTER \*between myofibrils = mitochondria and elements of sarcoplasmic reticulum DYSTROPHIN - binds actin to plasmalemma of muscle cells - structural integrity
154
What is this slide showing?
Fibre arangement transverse
- Actin and myosin = dots
Between myofibrils may see parts of Z tubules and sarcoplasmic reticulum
