Blood Flashcards
general composition of blood:
plasma + formed elements: - - erythrocytes (RBC), leukocytes (WBC), platelets
clotting occurs by:
formed elements and serum (plasma without
type/ function of blood:
specialised ct.
- for transport (of nutrients, remove end products, hormones)
- regulation (homeostasis)
- protection
blood composition of centrifuged blood and %:
hematocrit (RBC at bottom)
- 35-45% women
- 40-50% men
buffy coat (WBC middle)
plasma at top
plasma function:
maintains osmotic pressure, transport, clotting, immune function
plasma features:
aqueous solution (90% water)
solutes:
- proteins (7-8%): albumin, globulins (incl. immunoglobulins), (help clot) prothrombin + fibrinogen
- electrolytes
- nutrients, blood gases, hormones, waste products
where are blood cell types originated?
all blood cell types: bone marrow ct.
- erthrocyte (RBC) only in blood
- leukocyte (WBC) in other ct. and blood
function of erythrocytes and brief info:
RBC: oxygen and co2 transport
heamoglobin (protein + iron) carries oxygen
shape of erythrocytes:
biconcave disc, to increase SA:V ration
mature cells: no nucleus or organelles
lifespan of erythrocytes and removed by:
in adults: approx 120 days
removed by spleen, bone marrow and liver
Anemia eg:
abnormally low heamoglobin conc. and/or RBC count
- iron deficiency
- pernicious (insuffcient B12- helps mature RBC/ change shape)
- aplastic
- sickle cell
how is blood groups classified:
from antigens on RBC
14: A/B/O/AB and +/-
function and shape of leukocytes:
defense,
spherical shape (in plasma) but some: ameboid/motile leaving blood vessels to invade tissues
2 classifications of cell type leukocytes: and how
type of granules and nuclei shape
- granulocytes (polymorphonuclear: PMNs)
- agranulocytes (mononuclear)
features: granulocytes
nuclei have 2+ lobes, specific granules (bind neutral/basic/acidic component of dye mixtures) special functions, azurophilic granules (stain purple)
features: agranulocytes
round of indented nuclei, only has azurophilic granules
types of granulocytes:
neutrophils, eosinophils, basophils
types of agranulocytes:
lymphocytes, monocytes
neutrophils: function/ shape/ %
most common (50-70%)
- multi lobed nucleus (3-4)
- phagocytic (lysosomes), central in response: infection, injury, inflammation
eosinophils: function/ shape/ %
1-5% leukocytes
- bi lobed nucleus
- large ovoid granules
- similar size to neutrophils
- proliferate in allergic reactions, parasite destruction, phagocytosis
basophils: function/ shape/ %
rare: < 1%
- similar size to neutrophils
- nucleus in irregular lobes (obscured by specific granules)
- allergy, inflammation, granules have heparin (anticoagulant), histamine (cause hypersensitive reactions: hay fever, asthma)
monocytes: function/ shape/ %
2-8%
- largest of leukocytes
- nuclei indented (kidney bean/ horseshoe)
- pale cytoplasm
- phagocytic (engulf foreign microorganisms, dead/worn out cells, other tissue debris)
- close interactions with lymphocytes to recognise/ destroy foreign substances
lymphocytes: function/ shape/ %
20-40%
- small/ med/ large
- deeply staining nucleus, relatively thin rim of cytoplasm, no specific granules
- recognise/ respond to antigens, for cell mediated immunity: viral infections
- T, B, NK cells
- can’t histologically distinguish T and B cells
basophils: found where/ lifecycle
found in tissues with allergic reactions
1-2 years approx
lymphocytes: found where/ lifecycle
leave capillaries/ venules-> ct. will differentiate into macrophages
days in blood
months in ct.
monocytes: found where/ lifecycle
seen in ct. and epithelium
- densely packed in lymphoid tissue (spleen, lymph nodes, tonsils)
months - years
lymphocytes: found where/ lifecycle
seen in ct. and epithelium
- densely packed in lymphoid tissue (spleen, lymph nodes, tonsils)
months - years
monocytes: found where/ lifecycle
leave capillaries/ venules-> ct. will differentiate into macrophages
days in blood
months in ct.
difference btw eosinophils/ basophils:
more likely eosinophil than basophil
- eosinophil: 2 lobes equal size, dense granules in cytoplasm
- basophil: 2-3 lobes less defined, less granules- not dense mass
larger than usual no. of neutrophils may indicate:
acute or chronic infection
? increases due to allergic disorders:
basophils and eosinophils
leukaemia may have:
large no. of immature leukocytes
thrombocytes: features and ?/ml
- fragments of cells
- no nuclei but have mitochondria, ribosomes, enzyme systems and 4 types of granules
- 250 000 - 500 000/ ml
thrombocytes: function and life span
- promote coagulation
- repair gaps in blood vessel walls: aggregation, adhesion to self and endothelium,
- also activate clotting factors in plasma: fibrin, release serotonin (for vasorestriction)
10 days
what blood cells formed in: myeloid tissue
red bone marrow:
- erythrocytes
- granular leukocytes (neutro/basal/eosinophils)
- thrombocytes (platelets)
what blood cells formed in: lymphoid tissue
lymph nodes, spleen, thymus:
- agranular leukocytes (mono/lymphocytes)
what blood cells formed in: during embryonic and foetal development
yolk sac, liver, spleen
? stem cells give rise to all cell types:
pluripotent stem cells
- under control of cytokines and growth factors
