Microanatomy - Histology of Hematopoietic System Flashcards
what is hematocrit?
what do u add to blood sample to measure hematocrit?
what method is used to display blood cells? (which stain?)
is the volume percentage of red blood cells in blood, measured as part of a blood test: normally ~ 45%
- add an anticoagulant, like heparin, to prevent clotting
- display blood cells: blood smear - wrights stain
what % of plasma is water / solids?
what makes up solids of plasma?
- 91/2% = water
- 8/9% = solids
plasma solids:
- coagulants (like fibrinogen)
- proteins (albumin): maintain osmotic pressure and transport other proteins
- electrolytes: stabilise pH
- immunoglobuilins
erythrocytes:
- shape?
- lifespan?
- where do they get destroyed?
- what are they replaced by?
- where are they produced?
- shape: biconcave
- lifespan: 120 days
- where do they get destroyed: in the spleen
- what are they replaced by: reticulocytes
- where are they produced: bone marrow
platelets:
how are they produced?
function? basic
- small fragments derived from megakaryocyte
- megakaryocytes develop cytoplasmic projection: become proplatelets -> platelets (after 7-10 days)
- function in coagulation
where do u find megakaryocytes?
what do they look like?
- in bone marrow
- much larger than other cells
- lobated nucleus
how does haemostasis occur? (basic)
what happens if have low platelet levels? name for this
which stage in haemostasis doesnt occur if dont have clotting factors?
- *primary haemostasis:**
- platelets form an initial plug: platelet plug
- *secondary haemostasis:**
- clotting proteins produce a firm thrombus
//
- low platelet levels: thromobocytopenia - bleeding and bruising
- low clotting factors: haemophiliia - no secondary haemostasis
symptoms & examination signs of anaemia?
- *symptoms**:
- tired
- faint
- angina
- rapid heart beat
- *signs:**
- pale
- tachycardia
- bounding pulse
- systolic flow murmur
- cardiac failure
- retinal haemorhagge
what are causes of anaemia? which is the main?
- *-** most common cause: iron deficiency
- infection (hookworm)
- growth spurt
- pregnancy
- cancer
but: anaemia is caused by something else / an underlying cause -> have to find this
how do u subdivide different types of anaemia based on mean cell volume? (3)
based off mean cell volume (MVC)
- microcytic: MVC <80 fL (rbc are smaller than usual)
- *- normocytic:** MVC 80 -100 fL (normal sized, but just less off them an expected)
- *- macrocytic:** MVC > 100 fL (rbc are larger than usual)
what are the following caused by?
- microcytic:
- normocytic:
- macrocytic:
- microcytic: iron deficiency, thalassaemia (an inherited blood disorder that causes your body to have less hemoglobin than normal)
- normocytic: acute blood loss, renal failure, SCA, leukaemia
- macrocytic: alchohol and liver disease
how do u subdivide anaemia by production of rbc?
increased destruction: high reticulocytes. due to bleeding or haemolysis
reduction production: low reticulocytes. anaemia of chronic disease, aplasia, cancers
which leukocytes are granular (3) and agranular? (2)
which leukocytes are most and least common?
- *granular:** neutrophils, basophils, eosinophils
- *agrunular:** monocytes, lymphocytes
most common: neutrophils
least common: basophils
- role of neutrophils? - how do they do their antimicrobial functions (3)
- what is the name of when neutrophils go through endothelium?
- what happens at end of neutrophil life?
1. role: respond to pathogens invading the body
- constantly patrol for infection
- trap and kill invading pathogens: phagocytosis, degranulation and neutrophil extracullar traps
- when migrate through endothelium: diapedesis
- multi step (see photo)
3. end of neutrophil life: The efferocytosis (engulfment of apoptotic cells by phagocytes) of apoptotic neutrophils by macrophages promotes anti-inflammatory signaling, prevents neutrophil lysis, and dampens immune responses.
what is neutrophilia?
what is neutropenia?
when do you see each?
- *neutrophilia:** increase in neutrophils
- infection
- inflammation
- tissue damage
- haemorrhage
- *neutropenia:** decrease in neutrophils
- HIV
- sepsis
- bone marrow failure, leukaemia
- medications
what are eosinophils and basophils associated with?
eosinophils: allergic reaction, parasitic infections & chronic inflammation
basophils: variety of causes (e.g. chronic myeloid leukaemia)
which cells are found in the blood (8) and which are found in tissue (5) - focus on tissue
- *blood**:
- platelets
- erythocytes
- basophils
- neutrophils
- eosinophils
- monocytes
- NK cells
- small lymphocytes
- *tissues:**
- mast cells
- macrophage (derived from monocytes)
- B & T cells
- plasma cells
- where do u find accumulations of lymphocytes that are not in secondary lymphoid tissue
The mucosa of the digestive, respiratory and urinary tracts often contains small aggregations of lymphocytes called lymphoid follicles. These are called ‘Mucosa associated lymphoid tissue’ (MALT).
sites of initial immune response
what happens in lymph nodes?
describe the structure - (capsule, trabeculae & reticular tissue?)
in which part of lymph nodes do u find b and t cells?
- maintain / differentiate B cells (plasma & memory cells)
- home for T cells
- detect and react to lymph-borne antigens
- *structure:**
- covered in a capsule made from dense connective tissue
- capsular extensions, of deep connective tissue, called the trabeculae, which provide support for blood vessels entering into the nodes
- reticular tissue: provide additional support to the matrix/stroma.
The nodes are covered by a capsule of dense connective tissue, and have find lymphocytes
- cortex (under the capsule) - lymphoid follices: B cells
- deep cortex: **T cells
- medulla:B cells (**immature)
what happens to thymus after puberty?
strucutre:
- surrounded by?
- subdivides into?
- where are developing T cells found?
- thymus after puberty: turns into adipose tissue
- *-** It has two lobes (bilobular) divided up into many lobules
- cortex: highly cellular, outer, more darkly staining region.
- medulla: inner lighter staining region is less cellular
- *- CT** surrounds the thymus as a **capsule
- parenchymacontains developing T cells (thymocytes)** in an extensive meshwork formed by epithelioreticular cells
label these parts of thymus histology :)
what are epithilioreticular cells?
* where do u find macrophages in thymus? *
what are hassals corpuscles?
thymus macrophages: in the cortex
hassals corpuscles: concentric layers of flattened reticular epithelial cells filled with keratohyalin granules and keratin.
what is parenchyma (white pulp and red pulp) named based off?
what is found within white and red pulp?
based of colour of fresh sections !! not processed tissue
white pulp: B and T cells, APCs and plasma cells
red pulp: old & damaged RBC, macrophages, lymphocytes
The red pulp makes up roughly 80% of the spleen parenchyma. It is separated from the white pulp by the marginal zone. The red pulp is primarily made up of tissue known as the cords, which is rich in macrophages, and the venous sinus.
label this bit of spleen :)
