Senario One - Blood and Immunity Flashcards
List the three main functions of the blood
transport, protection, homeostasis
What is the blood responsible for transporting?
oxygen and carbon dioxide, nutrients, waste products, lactic acid
How is the blood responsible for protection?
Providing the immune system and clotting to prevent blood loss
What is the role of the blood in homoeostasis
Controlling hormones, enzymes, PH and temperature
What are the main components of plasma and their percentages?
Protiens - 7% Water - 91.5% Other solutes - 1.5%
What are the main proteins found within the blood?
Albumins - 54% Globulins - 38% Fibrinogen - 7%
What solutes are found in plasma?
electrolytes, nutrients, gases, regulatory substances and waste products
what is the purpose of water within the blood plasma?
absorbs, transports and releases heat solvent and suspending medium
what is the function of Albumins?
maintenance of osmotic balance and exchange of fluids across the capillary wall
what is the function of globulins?
produce immunoglobulins - for virus and bacteria defense produce alpha and beta globulins for transport of iron, lipids and fat-soluble vitamins
what is the function of fibrinogen?
blood clotting
Main function of all plasma proteins?
colloid osmotic pressure contribute to blood viscosity transportation of hormones, fatty acids and calcium regulation of blood pH
what is the function of electrolytes?
maintain osmotic pressure, important in cell function
what is the function of nutrients
essential for cell function, growth and development
what gases are found within the blood plasma and what are their role?
oxygen - cell function carbon dioxide - blood pH nitrogen - no known funciton
what are the regulatory substances of blood plasma - and their function?
enzymes - catalyse chemical reactions hormones - regulate metabolism, growth and development vitamins - cofactors for enzyme reactions
what are the waste products found in the blood?
breakdowns from protein metabolism urea, uric acid, creatinine, creatine, bilirubin, ammonia
how many erythrocytes are there in normal circulation?
4.8-5.4 million/microlitre
what size are erythrocytes?
7-8 micrometers in diameter
what are the characteristics of an erythrocyte?
biconcave disc without nuclei strong and flexible plasma membrane lack mitochondria - so produce ATP anaerobically live for 120 days contains high [haemaglobin]
Function of erythrocytes?
haemoglobin within RBC transports oxygen and some Co2 in the blood
What are the 5 types of leukocytes and their common function?
neutrophils eosinophils basophils lymphocytes - B cells, T cells, NKCs Monocytes combat pathogens and other foreign substances that enter the body
How many leukocytes are there in the body?
5000-10000 per microlitre
how long to leukocytes live?
few hours to a few days
What is the size and structure of a neutrophil?
10-12 micrometres nucleus has 2-5 lobes connected by thin strands of chromatin, finely granulated cytoplasm
what is the function of neutrophils?
phagocytosis, destruction of bacteria with: - lysozyme - defensins - strong oxidants
what is the abundance of neutrophils in WBCs?
60-70%
what is the size and structure of an eosinophil?
10-12 micrometres 2 lobes in the nucleus, connected by a thick strand of chromatin large granules within the cytoplasm
what is the function of eosinophils?
combats the effect of histamine in allergic reactions phagocytose antigen-antibody complex destroy parasitic worms
what is the abundance of eosinophils in WBCs?
2-4%
what is the size and structure of basophils?
8-10 micrometres nucleus has 2 lobes large cytoplasmic granules
what is the function of basophils?
liberate heparin, histamin and serotonin in allergic reactions to intensity inflammatory response change haemodynamics and recruit cells in inflammation
what is the abundance of basophils in WBCs?
0.5-1%
what is the structure of lymphocytes?
range from 6 - 14 micrometers (the small lymphocytes are the smallest blood cell) round or slightly indented nucleus cytoplasm forms a rim around the nucleus
what is the main functions of lymphocytes?
mediation of immune response and antigen-antibody reactions
what is the abundance of lymphocytes in WBCs?
20-25%
what is the structure and size of monocytes?
12-20 micrometres - the largest kidney shaped nucleus and ‘foamy’ cytoplasm
what is the function of a monocyte?
phagocytosis - after transforming into a macrophage when leaving the blood
what is the abundance of monocytes in WBCs?
3-8%
what are the 7 defence mechanisms of the non-specific immune response?
?skin mucous membranes reflexes - cough and sneeze natural killer cells phagocytes inflammation fever
what is the role of the skin in non-specific resistance?
tightly packed cells prevent penetration waterproof produces acidic sebum, which bacteria are unable to survive in produces sweat containing lysozyme - breakdowns the proteins in the bacteria - unable to survive
what is the role of the mucous membranes in non-specific response?
Hairs in upper tract and cilia in lower tract mechanical waft substances towards the exit mucus acts as sticky surface to trap foreign bodies secretions - tears and salvia - contain lyzozyme gastric juices - low pH 2 - bacteria can’t survive
what is the role of reflexes in the non-specific response?
cough and sneeze - expel towards exit
what is the role of NKCs in the non-specific response?
attack abnormal body cells non-specifically spray the abnormal cell with poison - usually some healthy cells die in the process deficient in cancer patients so abnormal cells can poliferate
what is the role of phagocytes in the non-specific response?
neutrophils and monocytes recruited by chemical signalling to damaged site engulf bacteria r debris removing it from the area neutrophils die once ingested something monocytes are in lower quantity and take longer to be recruited but don’t die dead monocytes and neutrophils = pus
what is the role of inflammation in the non-specific response?
Basophils recruited cause vasodilation and prevent blood clotting too quickly - to allow additional leukocytes to be recruited lead to 5 cardinal signs of inflammation
what is the role of fever in the non-specific response?
pyrogens from WBCs to hypothalamus to reset bodies internal temperatures - body thinks its cooler than it is and so increases body temp high temp increases rate of reactions so pathogen eliminated more quickly - increased phagocytosis - division of pathogen decreases due to high temp
what is the structure of platelets
2-4 micrometer fragments formed from megakaryocytes - splinter into 2000-3000 fragments - become enclosed in plasma membrane - forming the platelet many vesicles, no nucleus last 5-9 days
Function of platelets
form platelet plug in haemostasis release chemicals promoting vascular spasm and blood clotting
what is the extrinsic pathway?
few seconds following trauma trauma to blood vessel means tissue factor leaks into the blood from outside the blood vessel causes formation of prothrombinase
what is the intrinsic pathway?
within a few minutes endothelial cells roughened or damaged - mean collagen fibres within CT of Bv are exposed – platelets in contact with collagen fibres form clotting factor damaged endothelial cells cause damage to platelets - release of phospholipids clotting factor and phospholipids act with calcium to form prothrombinase
what is the common pathway
once prothrombinase has been formed, acts with calcium to catalyse reaction converting prothrombin to thrombin thrombin confers fibrinogen into insoluble fibrin strengthens links between adhered platelet - plugs the Bv preventing blood loss , then contracts to bring walls of Bvs close to gether
what is intravascular clotting
clots form within the CVS due to roughened endothelial surface - triggered by atherosclerosis, trauma or inflammation OR due to blood stasis causing an accumulation of clotting factors
what its an embolus?
a travelling clot, air bubble, fat or debris within the CVS
what is a thrombus?
clot formed within the CVS
what is the structure and function of an elastic artery?
TI: well defined TM: thick and dominated with elastic fibres TE: thicker than TM transfer blood from he heart to the muscular arteries
what is the structure and function of a muscular artery?
TI: well defined TM: thick and dominated with smooth muscle fibres TE: thicker than TM distribute blood to arterioles
what is the structure and function of an arteriole?
TI: thin - with fenestrated lamina TM: 1-2 layers of smooth muscles - distally forms pre-capillary sphincter TE: loose and collagenous CT w/ symphathetic nerves Deliver blood to capillaries whilst regulating blood flow from the heart
what is the structure and function of a capillary
TI: endothelium and basement membrane No TM or TE permits exchange of substances with tissues delivers blood to post capillary venules
what is the structure and function of a post capillary venule
TI: endothelium and basement membrane No TM Sparse TE permits exchange of substances with tissues delivers blood to muscular venules
what is the structure and function of a muscular venule
TI: endothelium and basement membrane TM: 1-2 layers of smooth muscle TE: sparse Pass blood into the vein, act as reservoirs for large volumes of blood.
what is the structure and function of veins
TI: Endothelium and basement membrane containing valves – with larger lumen than artery TM: v. thin, with no external elastic lamina TE: thickest layer return blood to the heart - facilitated by valves
what is the tunica intima?
internal lining - direct contact with the blood Three parts: - endothelium - flattened cells, smooth frictionless surface - basement membrane - deep to endothelium - anchor for the endothelium - collagen make resilient to stretching and recoil - internal elastic lamina - boundary to tunica media - elastic sheet with openings to allow transfer between TI and TM
what is the tunica media?
muscle connective tissue layer - containing smooth muscle and elastic tissue regulates the diameter of the lumen internal elastic lamina forms boundary with TE
what is the tunica externa?
outer covering - elastic and collagen fibres contains nerves and tiny Bvs to supply the smooth muscle of TM anchors Bv to surrounding tissues
