Circulatory System: Blood Flashcards
What are the three main components of the circulatory system?
heart, blood vessels, and the blood
What cardiovascular system only refers to ____
the heart and the blood vessels
Hematology is the study of ___
blood
What are the three main functions of the circulatory system?
Transport
protection
regulation
What does the Circulatory system transport?
Oxygen, CO2, nutrients, wastes, hormones and stem cells
How does the Circulatory system protect?
Limits the spread of infection, causes inflammation, destroys microbes and cancer, neutralizes toxins, and initiates clotting
What does the Circulatory system regulate?
Fluid balance, pH, Temperature control
How much blood do adults have?
4-6L
What is blood?
A liquid connective tissue consisting of cells and extracellular matrix.
What is the extracellular matrix of blood?
Plasma
What are the formed elements of blood?
RBC’s, WBC’s, and platelets
What are erythrocytes and leukocytes?
red blood cells and white blood cells
What are the two categories of leukocytes?
Granulocytes and Agranulocytes
What are the three Granulocytes?
BEN
Neutrophils
Eosinophils
Basophils
What are the two Agranulocytes?
LM
Lympocytes
Monocytes
How many types of formed elements are there?
7
Plasma makes up ____ of blood
Erythrocytes make up ___
and WBC’s and platelets make up ___
55
45
<1%
What is the Buffy coat when blood is separated?
WBC’s and platelets
What is serum and how is it different from plasma?
Serum is the remaining liquid after blood clots
it is identical apart from the absence of fibrinogen which was used during clot formation
What are the three major types of plasma proteins?
Albumin’s
Globulin’s
Fibrinogen
What are Albumins?
- The smallest and most abundant plasma proteins
- They contribute to blood viscosity and osmolarity
- influence blood pressure, flow, and fluid balance
What are Golbulins?
- Antibodies
- Provide immune function
- 3 types Alpha, Beta, Gamma
What is Fibrinogen?
The precursor to fibrin. involved in clotting
Where are plasma proteins formed?
the liver except gamma globulin’s (produced by plasma cells)
What are the Nitrogenous compounds that are found in plasma?
- Free amino acids from dietary protein and tissue breakdown
- Nitrogenous wastes (urea)
What is urea as product of and how is it removed from the body?
it is a product of catabolism and is removed by the kidneys
What are the 3 main gasses that are found dissovled in plasma
02, C02, nitrogen.
What is the main electrolyte found in blood plasma?
Na+ makes up 90% of all plasma cations
What is viscosity?
The resistance of fluid to flow resulting from the cohesion of the particles
Whole blood is ___ times as viscous as water
Plasma is ___
- 5 to 5.5
2. 0
What is osmolarity of blood?
the total number of those dissolved particles that cannot pass through the blood vessel wall
What occurs if the blood osmolarity is too high?
the blood will absorb too much water increasing blood pressure
What occurs if the blood osmolarity is too low?
too much water stays in the tissues droping blood pressure ad causing edema
How is optimum osmolarity regulated?
Regulation of sodium ions, proteins, and RBC’s
What is hemopoiesis?
the production of blood especially its formed elements
What are hemopoietic tissues?
tissues the perform hemopoiesis
What is the yolk sacs role in hemopoesis ?
Produces the stemcells that produce the first blood cells and they colonize fetal bone marrow, livers, spleens, and the thymus
What is the Livers role in hemopoesis?
Produces only in fetus stops after birth
What is the spleens role in hemopoesis ?
continues to Produces lympocytes
What is the main producer of all 7 formed elements of blood?
Red bone marrow
What are pluripotent stem cells? (PPSC)
-Formally called hemocytoblasts and hemopoietic stem cells
Stem cells that produce formed elements of blood
What is a Colony-forming unit?
A specialized stem cell that only produces one class of formed element of blood
What is Myeloid hemopoiesis?
blood formation in the bone marrow most common
What is Lymphoid Hemopoiesis?
blood formation in the lymphatic organs only lymphocyte’s after infancy
What are the two primary functions of erythrocytes?
- Carry oxygen from lungs to cell tissues
- Pick up CO2 from tissues and bring to lungs
Erythrocytes discard what two organelles during development?
Mitochondria
Nucleus
How to erythrocytes produce ATP?
Via anaerobic fermentation
How is blood type determined?
By surface glycoproteins and glycolipids
What two cytoskeletal proteins give erythrocytes durability and resilience? What does this allow erythrocytes to do?
Spectrin and Actin
Allows them the strech and bend to squeeze through small capillaries
What % of the cytoplasm of erythrocytes is hemoglobin?
33%
What is the function of Carbonic anhydrase in the cytoplasm of erythrocytes?
It converts CO2 into carbonic acid which allows for easy transport to the lungs and wells as helps maintain pH balance
What is the importance of the four globins (protein chains) that are present in Hemoglobin?
They bind CO2
What is the importance of the Heme groups in hemoglobin?
That are non-proteins that bind O2 to ferrous ions at their center.
What is hematocrit?
Packed cell volume
% of whole blood volume composed of RBC’s
Why do women have lower Hematocrit levels?
Less androgens
menstrual loss
inversely proportional to percentage of body fat
What is Erythropoiesis?
The production of RBC’s
How long is the development and What is the average lifespan of erythrocytes?
3-5 days to develop
120 day lifespan
What is the first committed cell in the development of RBC’s?
A hemopoietic stem cell differentiates into a colony-forming unit (CFU)
What hormone is released from the kidneys that in involved in erythropoiesis?
erythropoietin
EPO
What do CFU cells become in the process of erythropoiesis?
They become Erythroblasts
What do erythroblasts begin to synthesize?
Critical component of RBC’s
Hemoglobin
What do erythroblasts become? What event is part of this transformation
They become reticulocytes once the nucleus is discarded from the erythroblast
Why are reticulocyte’s named as such?
because of their fine network of endoplasmic reticulum
What percentage of circulating blood consists of still developing reticulocytes?
0.5-1.5%
Explain the process of erythropoesis and all of the cells involved. also what hormone regulates the process and where does it come from?
- Erythropoietin(EPO) from the kidneys regulates the process
- Hemopoietic stem cell differentiates into a colony-forming unit
- CFU becomes a Erythroblast the begin to synthesize hemoglobin
- Erythroblasts eject their nuclei and become reticulocytes
- Reticulocytes mature to become erythrocytes * some may enter the bloodstream prematurely
How many steps in the process of iron metabolism?
8
What two main bodies are involved in iron metabolism?
Stomach and Liver
What is the general process of iron metabolism in the stomach?
Ingested iron is converted into its bio available form and binds to gastroferritin and is transported to the small intestine for absorption
What is the general process of iron metabolism in the liver?
- Iron from the blood stream is transported via transferrin
- some iron is released for storage
- the remaining iron is sent to other organs
What protein does iron bind to in the liver when it is being stored? What is it stored as?
apoferritin
to be stored as ferritin
What is the bioavailable form of iron? What two types are ingested normally and what converts it into the Bioavailable type?
- Fe2+ is the bioavailable form
- Fe2+ and Fe3+ is ingested
- Stomach acid converts Fe3+ into Fe2+
What is the role of Vit B12 and Folic acid in the process of erythropoiesis?
They allow for the rapid cell division and DNA synthesis needed during erythropoiesis
What is the role of Vit C and copper acid in the process of erythropoiesis?
They are cofactors for enzymes that synthesize hemoglobin
What is the name of the alpha globulin that transports copper in the blood?
ceruloplasmin
Explain the negative feedback loop that controls erythrocyte homeostasis
- Low blood count causes hypoxemia
- The low O2 levels are detected by the kidneys
- the kidneys produce more erythropoietin (EPO) to stimulate the bone marrow
- RBC increases in 3-4 days
What are four main causes of increased erythropoiesis?
- Hypoxemia
- High altitude
- Increased exercise
- Loss of lung tissue in emphysema
Where do expired erythrocytes begin the process of death and disposal?
Liver and spleen
What is the first stage of Death and disposal of Erythrocytes?
Hemolysis in narrow channels of spleen and liver
What happens to the erythrocytes after they go through hemolysis?
- Heme is separated from Globin
- Globin’s are hydrolyzed into amino acids
- iron is removed from heme
- Macrophages digest leftover bits
What happens to the iron after it is removed fro heme?
It is stored and reused
What are the four steps in the breakdown of Heme after iron is removed?
GYKL
- Heme Pigment is converted into biliverdin
- Biliverdin is converted into Bilirubin
- Bilirubin is released into blood plasma(kidneys-yellow urine)
- Liver removes bilirubin and secretes it into bile and is the excreted
What do bacteria create in the small intestine to help digest bilirubin?
urobilinogen
makes feces brown
What is polycythemia?
What are the two types and their differences?
- It is an excess of RBC’s
- Primary is caused by a cancer of erythropoietic cell lines in red bone marrow
- Secondary is caused by environmental factors such as dehydration, emphysema, high altitude, or physical conditioning.
What are the dangers of polycythemia?
Increased blood volume leads to increased blood pressure, viscosity can lead to embolism, stroke, or heart failure
What are the three categories of anemia?
- Inadequate erythropoiesis or hemoglobin synthesis
- Hemorrhagic anemia’s from bleeding
- Hemolytic anemia’s from RBC destruction
What type of anemia does kidney failure cause?
Inadequate erythropoiesis due to insufficient production of (EPO) erythropoietin
What is Pernicious anemia?
Autoimmune attack on stomach tissue that leads to inadequate absorption of Vit B12
What is hypoplastic anemia?
The slowing of erythropoiesis
What is aplastic anemia?
Complete cessation of erythropoiesis
What are the three potential consequences of anemia?
- Tissue hypoxia and necrosis
- Blood osmolarity is reduced, producing edema
- Blood viscosity is low causing low pressure and possible cardiac failure
What is sickle-cell anemia
general overview
- Genetic defect effects the 6th amino acid of the beta chain changing the structure of Hb to HbS
- RBC’s become sticky and rigid
- RBC’s stic together and are pulled into a sickle shape.
What is sickle cell anemia’s relationship with the malaria parasite?
Causes resistance to malaria
Who discovered the ABO blood types? What year?
Karl Landsteiner
1900
Blood types are based on interactions between _____ and _____
Antigens and antibodies
What are antigens?
Complex molecules on the surface of cell membranes that activate immune response
What are agglutinogens?
Antigens on RBCs that are the basis of blood typing
What are antibodies? what do they do?
- Proteins (gamma globulins) secreted by plasma cells
- Part of imune response
- binds to foreign antigens to mark them for destruction
What are agglutinins?
antibodies in the blood plasma that bring about transfusion mismatch
What is agglutination?
The clumping of RBC’s due to an antibody molecule binding to antigens
What are the names of the two RBC agglutinogens? What determines them?
Antigen A
Antigen B
determined by glycolipids on RBC surfaces
Blood type is determined by the presence or absence of ___ on RBC’s
antigens
What is the most common ABO type? Least common?
most common is O
Least is AB
Why is mismatched blood type transfusion a bad thing?
- your body’s antibodies attach to the antigens of the foreign blood and cause it to clump (agglutination)
- These agglutinated RBC’s can block small blood vessels and release their Hb
- the released Hb can block kidney tubules and cause renal failure
What is Rh?
an agglutinogen that was discovered in rhesus monkeys accounts for the positive or negative factor of ABO blood types
What is the most reactive Rh antigen? What does its presence determine?
Rh D
Determines whether or not the patient is Rh positive or not
What is hemolytic disease of newborns? (HDN)
What causes it how can it be prevented?
If an Rh- mother produces antibodies against an Rh+ fetus they will travel across the placenta and cause a loss of blood in the fetus.
due to second Rh+ child, Rh+ transfusion before pregnancy,
prevented using the drug RhoGAM that binds to fetal agglutinogens so the mother doesnt form Rh D antibodies
What is the least abundant formed element in blood?
leukocytes
What is the general function of leukocytes?
They protect against infectious microorganisms and other pathogens
How long do Leukocytes spend in the blood stream?
few hours until they migrate to connective tissue
What are granules in leukocytes?
Lysosomes can azurophillic granules
What are granulocytes?
Leukocytes that have specific granules that contain enzymes and other chemicals that are defensive
What are the three Granulocytes?
Most to least common
Neutrophils
Eosinophils
Eosinophils
What are the two agranulocytes?
Lymphocytes
Monocytes
What is the function of neutrophils?
they are aggressive antibacterial WBC’s
What is neutrophila?
A increase in the number of neutrophil due to bacterial infection
When do the numbers of eosinophils increase?
When there is a parasitic infection, collagen diseases, allergies, and dieases of the spleen and CNS
What is the function of eosinophils?
The phagocytosis of antigen-antibody complexes, allergens, and inflammatory chemicals
the release of enzymes to destroy large parasites
What are the two substances the basophils release?
Histamine
Heparin
What does histamine do?
It acts as a vasoconstrictor and speeds up the flow of blood to an injured area
What does Heparin do?
Acts as an anticoagulant
promotes the mobility of other WBC’s in the area
What are the functions of lymphocytes?
- They destroy cells
- present antigens to activate other immune cells
- Coordinate actions of other immune cells
- secrete antibodies and provide immune memory
What are the functions of monocytes?
-They leave the bloodstream to become macrophages
What is leukopoiesis?
the production of white blood cells?
What are the leukocyte cell types that differentiate from Hemopoietic stem cells? (HPC’s)
Myeloblasts
Monoblasts
Lymphoblasts
What do meyloblasts give rise to?
- Neutrophils
- eosinophils
- basophils
What do monoblasts give rise to?
monocytes
What do lymphoblasts give rise to?
All forms of lymphocytes
Where do T-lymphocytes go to complete their develoment?
The thymus
Red bone marrow stores and releases what types of WBCs?
Granulocytes and Monocytes
DO circulating WBC’s stay in the blood stream?
no
How long do granulocytes stay in the bloodstream?
8hrs
How long do monocytes stay in the blood stream?
20 hrs
What is leukopenia?
low WBC count
What is leukocytosis?
High WBC count
What is leukemia?
Cancer of the Hemopoietic tissue that causes the high production of circulating leukocytes
What are the 5 values in a complete blood count?
HHTDR
- Hematocrit
- Hemoblobin concentration
- Total count for RBC’s reticulocytes, WBC’s, and platelets
- Differential WBC count
- RBC size and Hemoglobin concentration per RBC
What is hemostasis?
the sessation of bleeding
What is a hemorrhage?
excessive bleeding
What are the three hemostatic mechanisms?
VPB
Vascular spasm
PLatelet plug formation
Blood clotting
What cell forms platelets?
Megakaryocytes
What are some functions of platelets
– Secrete vasoconstrictors that help reduce blood loss
– Stick together to form platelet plugs to seal small breaks
– Secrete procoagulants or clotting factors to promote
clotting
– Initiate formation of clot-dissolving enzyme
– Chemically attract neutrophils and monocytes to sites of
inflammation
– Phagocytize and destroy bacteria
– Secrete growth factors that stimulate mitosis to repair
blood vessels
Explain the process of platelet formation
- Thrombopoiesis occurs as stem cells with thrombopoietan become megakaryoblasts
- megakaryoblasts grow very large to become megakaryocytes that live in bone marrow
- Megakaryocytes release fragments of their cytoplasm into the blood to become platelets
Where are most platelets stored?
the spleen
What is a vascular spasm?
Prompt constriction of a broken blood vessel to protect against further blood loss
What are the 3 causes of a vascular spasm?
- Pain receptors activate
- Smooth muscle is inured
- Platelets release vasoconstrictiors (serotonin)
What are the effects of Vascular spasms?
Prompt constriction of the broken vessels to provide time for the other clotting pathways
What is prostacyclin?
A platelet repellent that coats the endothelium of blood vessels
prevents unnecessary clot formation
Explain the process of platelet formation
- a broken vessel exposes its collagen
- platelets attach to the collagen and other platelets
- The platelets pseudopods contract drawing the platelets together and forming a plug
- The platelets release vasoconstrictors, ADP, and thromboxane A2
What is the function of the ADP released by platelets during plug formation?
to attract and degranulate more platelets
What is the function of the thromboxane A2 released by platelets during plug formation?
To promote platlet aggregation, degranultion, and vasoconstriction
How is the platelet plug process perpetuated?
via a positive feedback loop
What is coagulation? Give a brief overview of its process
Clotting caused by the conversion of fibrinogen to fibrin threads forming the framework of the clot
WHat are procoaguants?
Clotting factors produced by the liver that are present in the plasma
What are the three clotting pathways
the intrinsic and extrinsic that lead to the common
What is the extrinsic pathway initiated by? What is its cascade order?
Initated by thromboplastin (factor III)
cascades VII, V, X
What is the intrinsic pathway initiated by? What is its cascade order?
Initated by platlets reeasing Hageman factor (XII)
cascades XI, IX, VIII, X
What ion is required in all clotting pathways?
Calcium
After the X factor is activated by either pathway what is the brief sequence of events that complete the clotting?
-Factor X leads to the production of prothrombin
-prothrombin is converted into thrombin via prothrombin activator
-thrombin converts fibrinogen to fibrin
Fibrin creates a polymer and is cross-linked by XIII to create a framework
What is the positive feedback in the common clotting pathway?
Thrombin speeds up formation of prothrombin activator
How is clotting efficiency measured?
bleeding time after a 1mm deep incision
Clot retraction occurs within ___ minutes
30
What is the function of Kallikrein and what factor speeds up its production?
Converts plasminogen into plasmin (A fibrin-dissolving enzyme)
Factor XII
What is hemophila?
A hereditary disease that causes a deficiency in a clotting factor
What clotting factor is missing in Hemophillia A?
Factor VIII
What clotting factor is missing in Hemophillia B?
Factor IX
What clotting factor is missing in Hemophillia C?
Factor XI
What is a thrombosis?
An abnromal clott in an unbroken vesses
What is a thrombus?
a clot
What is a pulmonary embolism?
when a clot breaks free and travels to the lungs causing blockage
What is an infarction
tissue death due to clot blockage
What vitamin is required for clotting?
K
What class of drugs are warfarin, and cumarin?
Vit K antagonists
What does aspirin suppress what can reduce clotting?
Thromboxane A2
What is streptokinase?
an enzyme produced by streptococci bacteria that dissolves clots
WHat is TPA?
Tissue plasminogen activator
