Histology - Heart, Blood, Respiratory,GI Flashcards
1
Q
What is the pericardium?
A
The layer of cells surrounding the heart there is the visceral and the parietal pericardium. it is made of squamous epithelial cells
2
Q
What is the parietal pericardium?
A
The layer of the cells that goes on the inside of the fibrous sac of the heart.
3
Q
What layer is beneath the pericardium?
A
epicardium a fatty tissue.
4
Q
What is the structure and appearance of the myocardium?
A
striated muscle cells with a central nuclei with branching and have intercalated discs.
5
Q
What are intercalated disks?
A
They connect the actin filaments between myocytes they contain gap junctions transmit the electrical signals. they have adhering junctions with desmosomes.
6
Q
What is in the epicardium?
A
Arteries and veins and fatty connective tissue
7
Q
What is between the fibres of heart muscle?
A
Endomysium and can contain lymphocytes it is loose fibrous connective tissue.
8
Q
What hormone is released from the tissue in the atrium?
A
Atrial natriuretic peptide
9
Q
What is involved in the conducting system of the heart?
A
SAN AVN bundle of his purkinje fibres they are subendocardial not easily seen on H&E PAS can show glycogen rich plasma
10
Q
What is the inner most layer of the heart?
A
the endocardium which is a single layer of simple squamous layers this covers the valves too.
11
Q
What are the three layers of the valve?
A
Fibrosa, Spongiosa, and Ventricularis with endothelial cells on both sides.
12
Q
How many nuclei do cardiac muscle cells have?
A
one
13
Q
What is plasma?
A
blood minus the cells contained in it eg water salts minerals proteins hormeones and clotting factors
14
Q
What is serum?
A
Plasma minus clotting factors.
15
Q
How many RBCs are in a mL of blood?
A
4-6million
16
Q
What is the diameter of a RBC?
A
6.5-8.5um
17
Q
Where are red blood cells destroyed
A
in the liver and spleen
18
Q
What is the endoskeleton made of?
A
Spectrin
19
Q
What are granulocytes?
A
cells that have visible granules in them, Neutrophils eosinophils and basophils
20
Q
What are the agranulocytes?
A
Lymphocytes, Monocytes they are less common.
21
Q
What does the neutrophil look like?
A
It has a multi-lobed nucleus, a granular cytoplasm pale cytoplasm and is 12-14um wide contain myeloperoxidase.
primary granules are lysosomes
secondary granules are specific granules and secrete substances that mobilise inflamatory mediators
tertiary granules have gelatinases and adhesion molecules.
22
Q
What two types of stem cells are in the bone marrow?
A
Haematopoietic stem cells that form all the types of blood cell in the body and bone marrow stromal cells or mesenchymal stem cells these can produce fat bone and cartilage.
23
Q
Why do red blood cells use anaerobic respiration?
A
They contain few organelles so cannot do aerobic respiration.
24
Q
What proportion of WBC are neutrophils?
A
40-75%
25
What proportion of WBC are eosinophils?
5%
26
What proportion of WBC are basophils?
0.5%
27
What proportion of WBC are lymphocytes?
20-50%
28
What proportion of WBC are monocytes?
1-5%
29
What do eosinophils look like?
bi-lobed nucleus strongly eosinophilic granules eg look pink, crystalline losenge shaped crystals charcot-layden inclusions. can be hard to see nucleus due to granules
30
What do eosinophils do?
antagonistic to basophils, they often appear when. have receptors for IgE inhibit mast cell secretion come when there are parasitic infections and neutralise histamine
31
What do basophils look like?
the have dark-blue staining granules, the also have a bilobed nucleus but is often obscured by the granules
32
What is the function of basophils?
the have IgE receptors which help in the inflammatory response to allergens the granules contain histamine which can be released they are the circulating form of mast cells
33
What do lymphocytes look like?
Cant tell difference between B or T cells, they have a larged pink nucleus and small blue grey cytoplasm there are few granules.
34
What do Plasma cells look like?
Have an ecentrically located nucleus, chromatin is clumped making a clock shape???? the cytoplasm is basophilic giving it a blue colour there is a pale area near the nucleus called the perinuclear hoff produced by the golgi apparatus.
35
What do monocytes look like?
kidney bean shaped nucleus, non-granular nucleus.
36
What do platelets look like?
Anuclear small fragments of cells
37
What are the two lines of blood cell progenerators?
Common myeloid progenitors that produce all but lymphocytes and common lymphoid progenitor that produces lymphocytes
38
What is the general structure of bone marrow?
There are highly branches vascular sinuses and a reticulin scaffolding with interstices with haemopoietic cells.
39
What are reticulocytes?
immature red blood cells, they may have granules and a nucleus
40
When are you likely to see reticulocytes in the circulating blood?
Hypoxia or anaemia and with severe blood loss
41
Where in the myocardium are bundle branches?
in the septum
42
What is the function of thenasal cavity?
Smell and taste, transport filtration humidification warm
43
What is respiratory epithelium?
pseudostratified columnar, cilliated cells with interspersed goblet cells
44
What is the epithelium in the nose?
Nostrils is keratinised stratified squamous, behind it is non-keratinised the rest is respiratory epithelium
45
What is olfactory epithelium?
pseudostratiefed columnar cilliates but no goblet cells and cillia are stereocillia, it has basal epithelial cells, below it there are nerve fibres. has serous glands of bowman
46
Where is the olfactory epithelium?
Roof of nasal cavity down septum and lateral wall
47
What are bipolar neurons?
A neurone with the cell body in the centre and 2 axonal processes from either side.
48
What is the epithelium in the nasopharynx?
respiratory epithelium
49
What is the epithelium of the nasal sinuses?
respiratory epithelium
50
What is the larynx made of?
Hyline cartilage
51
What are the coverings of the larynx?
respiratory epithelium but not on vocal cords
52
What are the vocal chords lined with?
Stratified squamous epithelium overlying loose fibrous tissue called reinke's space no lymphatics
53
What supports the trachea?
Cshaped rings of cartilage contains seromucinous glands,
54
What fills the gap in the c shaped cartilage?
A muscle longditudinal called trachealis
55
What underlies main bronchi , lobar bronchi and segmental bronchi?
Smooth muscle partial rings respiratory epithelum neuroendocrinologie cells goblet cells
56
What is different about bronchioles?
Still have smooth muscle u has clara cells fewer goblet cells and cilliated columnar epithelium
57
What are clara cells?
they hace Mitochondrea sER secretory granules, no cillia vesicular cytoplasm not sure on function. could secret lipoprotein or stem cells in detoxifiers
58
What come after terminal bronchioles?
Respiratory bronchioles the start of gas exchange.
59
What are respiratory bronchioles structure?
cuboidal and cillated epithelium, smooth muscle and no cartilage
60
What are type 1 pneumocytes?
Flatterned cells with proud nucleus, 40% of cells 90% of SA few organelles inportant part of blood air barrier
61
What are type 2 pneumocytes?
60%of cells but 5-10% of surface, roundes to columnar rich mitochondria and ER in cytoplasm, they produce surfactant.
62
What can macrophages look like?
They have black aeas from carbon they phagocytose bateria
63
What are pores of Khon?
holes between alveoli that allow the spread of disease
64
What is the blood air barrier complex?
surfactant layer Membrane ot type 1 pneumocyte then cytoplasm and other membrane then basement membrane cell membrane of endothelial cell cytoplasm and other membrane then gets to the blood
65
What is the pleura like?
Flat mesothelial cells simple squamous.then loose fibrocollagenous tissue, then external elastic layer then fibrocollagenous layer then then irr`egular elastic layer.
66
What epithelium is the nasopharynx?
usually respiratory but can be squamous
67
What tissue is submucosal in the nasopharynx?
mucosa-associated lymphoid tissue.in waldeyer's ring
68
Where are beuroendocrine cells in respiratory epithelium?
in the basal layer they are very dark staining.
69
What is the difference between MALT and a lymph node?
Lymph nodes are encapsulated and MALT is associated with epithelium.
70
How are macrophages removed from the lungs?
Mucocilliary escalator or the lymphatics.
71
What is the fancy name for swallowing?
deglutination
72
What is the lining of the mouth?
Stratified squamous
73
What epithelium are the lips?
non-keratinising stratified squamous with a rete ridge system
74
what are the sebaceous glands of the mouth called?
fordyce's spots
75
What type of pithelium is the dorsal side of the tongue?
keratinising stratified squamous.
76
What type of epithelium is the ventral side of the tongue?
non-keratinising stratified squamous
77
How is the tounge divided into two regions?
anterior two thirds and posterior third is separated by a c shaped line of 6-10 dome shaped protrusions called circumvallate papillae
78
What are circumvalate papillae?
Have a moat around it with salivary glands and staste buds. they are flattened domes,
79
What characterises the posterior third of the tongue?
lymphoid tissue, in the form of mucosa associated lymphoid tissue. there are many salicary outlets here
80
What characterised the anterior two thirds of the tongue?
there are many papillae incluing circumvallate, filiform and fungiform
81
What doe filiform papillae look like?
they are most numerous type and are tall and narrow and pointed. They are keratinised especially at the tip. they don't have taste buds
82
What is the appearance of the fungiform papillae?
Randomly scattered mushroom shaped head they do contain taste buds.
83
What is the appearance of a taste bud?
Thin spindle shaped cells the full thickness of the epithelium in an oval cluster
84
What are the cells of the submandibular salivary gland like?
They are mixed so some dark some pale. there are purpleish staining zymogen granules.
85
How are the mucous cells aranged?
In a duct with a blind end and there are demilunes of zymogen rich serouc cells at the end.
86
What is the appearance of intercalated ducts?
Cuboidal or low columnar pale pink
87
What is the appearance of interlobar ducts?
Striated at the base tall columnar. It's biochemically active.
88
What is present in the parotid gland other than serous secreting cells?
Adipose tissue
89
What epithelium lines the oesphagus?
stratified squamous epithelium, lamina propria and muscularis mucosae. basal zone can be several layers thick being cuboidal or columnar.
90
What is odd about the lamina proproa?
It extends upwards in places into the epitelium.
91
Where is the thickest walls of the oesophagus?
Near the junction with the stomach.
92
What is the muscular arrangement in the oesophagus?
At the top quite random but lower down it is continuous sheets of longditudinal and circular mucosa. at the top some is skeletal but lower down it is all smooth continuous with the stomach
93
What is the abnormality that can occur at the oesphageal junction to the stomach?
It is most is stratified squamous but below diaphragm is columnar epitelium like the stomach. with exposure to acid the lower portion of the oesophagus can become columnar epithelium called barret's oesophagus
94
How long is the anal canal?
3-4cm long
95
What is the epithelium of the anal canal?
the upper region is columnar like the rectum and the lower is non keratinising stratified squamous type.
96
What is the pectinate(dentate line of the anal canal)?
marks the embruological separation of the anal membrane and the gut. there are anal glands at this level.
97
What are the plexuses of the anus?
Internal haemorroidal and external haemorrhoidal plexus of veins
98
What is are the valves of the GI tract?
The oesphagastric sphincter to stop stomach acid entering the oesphagus, the gastro-duodenal/ pyloric sphincter that controls emphtying of the stomach. there is the ileocecal valve between the ilium and the caecum. and the internal and external anal sphincter.
99
What is GALT?
Gut associated lymphoid tissue. produces lymphcytes plasma cells and macrophages often in submucosa
100
What are peyer's patches?
They are areas of GALT that have formed nodules int he terminal ilium
101
How many layers of muscle does the stomach have?
three layers there are the innernal oblique fibres followed by the circular fibres then longditudinal fibres.
102
What are the folds of stomach called?
Rugae
103
What are the functions of the gastric epithelium?
Produce HCl solution porteolytic enzymes enzymes and mucus to protect itself
104
What are the types of gastric mucous cells?
Surface and neck. surface mucous cells are tall and columnar with basal nuclei and clear staining cytoplasm the have some microvilli and a surface glycocalyx. Neck cells are smaller and less regular in shape, finely granular cytoplasm hard to identify
105
What are the acid producing cells like?
Parietal/oxyntic cells are pyramidal cells with pale eosinophilic cytoplasm and central nuclei. broad attachement to basal membrane. have an invagination called canaliculi for high SA
106
what do chief cells do and look like?
Produce pepsinogen and they are basal nuclei rich rER look like exocrin pancreas.
107
What do endocrine cells do?
The secrete serotonin and somatostatin and gastrointestinal polypeptide-like substance. and gastrin mainly in neck region
108
what is the structure of the stomach epithelium?
Three zones superficial neck and deep. downgrowths called crypts or pits.
109
What is common in the neck region?
Stem cells (immature),they migrate up and down to the other zones to replenish them
110
what is the deep zone like?
composed of glands with the base in muscularis mucosae.
111
What is the three different areas for the deep zones?
The cardia, body and pylorus
112
What is cardiac mucosa like?
superficial and deep zones are roughly equal in length small neck. surface has many mucous cells the, in the deep zone there are lots of acid secreting cells and endocrince cells they are coiled ducts. muscularis mucosea is quite thick
113
What is body mucosa like?
shorter superficial and longer deep zones. mainly mucous and enzyme and acid producing cells
114
What is pyloric mucosa like?
superficial can branch long and similar deep also branching. acid producing cells but also endocrine producing. more acid producing close to the sphincter.
115
What gives a larger surface area in the small intestine?
large folds called plicae circularis most pronounced in jejunum, the surface has villi and microvilli they also have crypts
116
What muscular layers are present in the small intestine?
Longitudinal and circular.
117
What are the three functional zones of the small intestinal epithelium?
Villi, crypts and neck zone
118
What types of cell are in the small intestine epithelium?
Entercytes, mucous cells, paneth cells, endocrine cells and stem cells
119
What are enterocytes?
Tall columnar cells round or oval nucleus in their lower section. they have the microvilli on them.
120
What covers the microvilli?
A glycocalyx which contains enzymes.
121
What organaelles are present in the enterocytes?
lots of lysosomes sER and centrioles golgi and mirochondria or Na ATPase
122
Where are mucous cells usually found in the small itestine?
In thr upper two thirds of the crypts and more in the ilium
123
Where are paneth cells found?
In the lower third of te crypt
124
What are paneth cells?
They are protein secreting cells the secrete defensins which are secreted and protect against infection.
125
Where are the endocrine cells located?
in the lower third of crypts mainly but also in the vili.
126
What do paneth cells look like on H&E stains
homogenous pink large red granules
127
What do endocrine cells look like?
Roughly triangular in shape broad base and narow apex to the lumen, spherical nucleus and pale staining
128
What do endocrine cells in the small intestine secrete?
Serotonin, enteroglucagon, somatostatin, secretin, gastrin Vasoactive intestinal peptide and motilin
129
Where are small intestine stem cells ?
In the lower third of the crypts
130
What is in the lamina propria of the small intestine?
Blood vessels and lymhatics. there are many lymphocytes in the lamina propria
131
How is the duodenum different from the rest of the small intestine?
It is retro peritoneal, the villi form ridge and leaf patterns and there are lots of mucous secreting bruners glands and it recieves secretons from the liver and pancreas
132
What is a burnner's gland?
They are mucous glands that secrete alkaline mucous they contain endocrine cells too.
133
What is the jejunum like?
It has the most developed villous system. most absorption happens there
134
Where do the secretions of the exocrine pancreas enter the duodenm?
The second part of the duodenum through the ampulla of vater controlled by the sphincter of oddi
135
What do the exocrine cells of the pancreas look like?
They are eosinophilic due to the zymogen granules.
136
What molecules do pancreatic enzymes break down?
Lipids, cholesterol starch peptides.
137
What is the pancreatic secretion like?
It is alkaline
138
What is the function of the large intestine?
to modify the fluid content of the faeces as it passes through.
139
What does the epithelium of the large intestine do?
absorbs water and salt and secrete mucous to lubricate
140
What is the epithelium like?
There are deep straight crypts that secrete mucous and endocrine secretions. mainly columnar some microvilli
141
What is the appendix like?
Blind ended diverticulum, 5-10 cm long and shrinks after aged 20
142
What is the structure like?
In a child it is lots of lymphoid and follicle formation.The epithelium is columnar like the large intestine.
143
Why can appendicitis occur?
When the end gets blocked it can trap bacteria and cause it to become infected
144
What substance is prominant in the stomach?
Elastin fibres
145
What can the parotid saliva contain?
Immunoglobulins
146
where are the intrinsic muscles of the tongue attached to?
Nowhere they are self contained
147
Where does the sublingual salivary duct go?
to many ducts but main one under the tongue
