Histology - Heart, Blood, Respiratory,GI Flashcards
What is the pericardium?
The layer of cells surrounding the heart there is the visceral and the parietal pericardium. it is made of squamous epithelial cells
What is the parietal pericardium?
The layer of the cells that goes on the inside of the fibrous sac of the heart.
What layer is beneath the pericardium?
epicardium a fatty tissue.
What is the structure and appearance of the myocardium?
striated muscle cells with a central nuclei with branching and have intercalated discs.
What are intercalated disks?
They connect the actin filaments between myocytes they contain gap junctions transmit the electrical signals. they have adhering junctions with desmosomes.
What is in the epicardium?
Arteries and veins and fatty connective tissue
What is between the fibres of heart muscle?
Endomysium and can contain lymphocytes it is loose fibrous connective tissue.
What hormone is released from the tissue in the atrium?
Atrial natriuretic peptide
What is involved in the conducting system of the heart?
SAN AVN bundle of his purkinje fibres they are subendocardial not easily seen on H&E PAS can show glycogen rich plasma
What is the inner most layer of the heart?
the endocardium which is a single layer of simple squamous layers this covers the valves too.
What are the three layers of the valve?
Fibrosa, Spongiosa, and Ventricularis with endothelial cells on both sides.
How many nuclei do cardiac muscle cells have?
one
What is plasma?
blood minus the cells contained in it eg water salts minerals proteins hormeones and clotting factors
What is serum?
Plasma minus clotting factors.
How many RBCs are in a mL of blood?
4-6million
What is the diameter of a RBC?
6.5-8.5um
Where are red blood cells destroyed
in the liver and spleen
What is the endoskeleton made of?
Spectrin
What are granulocytes?
cells that have visible granules in them, Neutrophils eosinophils and basophils
What are the agranulocytes?
Lymphocytes, Monocytes they are less common.
What does the neutrophil look like?
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.
What two types of stem cells are in the bone marrow?
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.
Why do red blood cells use anaerobic respiration?
They contain few organelles so cannot do aerobic respiration.
What proportion of WBC are neutrophils?
40-75%
What proportion of WBC are eosinophils?
5%
What proportion of WBC are basophils?
0.5%
What proportion of WBC are lymphocytes?
20-50%
What proportion of WBC are monocytes?
1-5%
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
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
What do basophils look like?
the have dark-blue staining granules, the also have a bilobed nucleus but is often obscured by the granules
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
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.
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.
What do monocytes look like?
kidney bean shaped nucleus, non-granular nucleus.
What do platelets look like?
Anuclear small fragments of cells
What are the two lines of blood cell progenerators?
Common myeloid progenitors that produce all but lymphocytes and common lymphoid progenitor that produces lymphocytes
What is the general structure of bone marrow?
There are highly branches vascular sinuses and a reticulin scaffolding with interstices with haemopoietic cells.
What are reticulocytes?
immature red blood cells, they may have granules and a nucleus
When are you likely to see reticulocytes in the circulating blood?
Hypoxia or anaemia and with severe blood loss
Where in the myocardium are bundle branches?
in the septum
What is the function of thenasal cavity?
Smell and taste, transport filtration humidification warm
What is respiratory epithelium?
pseudostratified columnar, cilliated cells with interspersed goblet cells
What is the epithelium in the nose?
Nostrils is keratinised stratified squamous, behind it is non-keratinised the rest is respiratory epithelium
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
Where is the olfactory epithelium?
Roof of nasal cavity down septum and lateral wall
What are bipolar neurons?
A neurone with the cell body in the centre and 2 axonal processes from either side.
What is the epithelium in the nasopharynx?
respiratory epithelium
What is the epithelium of the nasal sinuses?
respiratory epithelium
What is the larynx made of?
Hyline cartilage
What are the coverings of the larynx?
respiratory epithelium but not on vocal cords
What are the vocal chords lined with?
Stratified squamous epithelium overlying loose fibrous tissue called reinke’s space no lymphatics
What supports the trachea?
Cshaped rings of cartilage contains seromucinous glands,
What fills the gap in the c shaped cartilage?
A muscle longditudinal called trachealis
What underlies main bronchi , lobar bronchi and segmental bronchi?
Smooth muscle partial rings respiratory epithelum neuroendocrinologie cells goblet cells
What is different about bronchioles?
Still have smooth muscle u has clara cells fewer goblet cells and cilliated columnar epithelium
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
What come after terminal bronchioles?
Respiratory bronchioles the start of gas exchange.