Chapter 19: Cardiovascular System - The Blood

Name some chemicals found in blood vesicles used to help increase blood clot formation

- ADP - ATP - Ca+2 - serotonin - thromboxane A2 (which helps strengthen a blood clot). - platelet-derived growth factor (PDGF), a hormone that can cause proliferation of vascular endothelial cells, vascular smooth muscle fibers, and fibroblasts to help repair damaged blood vessel walls.

Intrinsic Pathway

- Occurs within blood, has direct contact with blood, doesn't require damage of blood vessels. - Trauma of endothelium tissue releases phospholipids by damaging platelets, activating clotting factor x. - Clotting factor x + clotting factor v form prothrombinase

FUNCTIONS: Albumins in Blood Plasma? Describe the size and how numerous they are as well.

- Smallest and MOST NUMEROUS plasma protein - FUNCTION: Maintain osmotic pressure, an important factor in exchange of fluids across blood capillaries.

FUNCTION: fibrinogen in blood plasma? Describe the size and how numerous they are as well.

-Large Plasma Protein -Aids in blood clotting

FUNCTIONS: Globulin in Blood Plasma? Describe the size and how numerous they are as well.

-Large plasma protein cells that produce immunoglobulin -FUNCTION: Immunoglobulin help attack viruses and bacteria. Alpha and beta globulins transport iron, lipids, and fat soluble proteins. Gamma globulin - turn into antibodies and aid in immune response against microbes and foreign pathogens.

Different types of anticoagulants

1. Antithrombin - blocks the actions of factors XII, X, and II (prothrombin). 2. Heparin - produced by mast cells and basophils, combines with antithrombin and increases its effectiveness in blocking thrombin. 3. Activated protein C (APC) inactivates clotting factors not blocked by antithrombin, activates inhibitors for plasminogen

Clotting can be divided into 3 steps. Briefly name and describe what happens in each step

1. Intrinsic and Extrinsic Pathway - the result of these two pathways lead to formation of prothrombinase (enzyme) 2. Prothrombin is converted into thrombin by prothrombinase (enzyme) 3. Thrombin converts soluble fibrinogen into insoluble fibrinogen. (forms thread of clots)

Red Blood Cells only live for about how many days?

120 days. WHY: Red Blood cells go through alot of wear and tear, squeezing through tight blood capillaries and arteries. Since they don't have a nucleus or other membrane bound organelles, they cannot regenerate from the damage they withstand over their short life time.

Hemoglobin also transports about ________ % of CO2 from body cells to the lungs for exhalation

23 percent

Blood consist of __________ % of plasma and ____________% of formed elements

55% Plasma 45% Formed Elements

Red blood cells lack what?

A nucleus and other organelles. Cannot reproduce or carry out extensive metabolic activities.

What are the 3 Main Functions of Blood?

A. Blood Transports Oxygen From the lungs to body cells, CO2 from body cells to the lungs for exhalation, nutrients from GI tract, heat, wastes, and hormones from endocrine system. B. Regulates pH (buffer system) , body temperature, and water contents in cells C. Prevents blood loss through clotting and combats toxins and microbes through phagocytic white blood cells or specialized protein cells.

Physical Characteristics of Blood

A. Viscosity greater than that of water (thicker & more sticky); temperature of 38 C (100.4 F), pH of 7.35-7.45 (slightly alkaline = basic) B. 8% of body weight, volume ranges from 4 to 6 liters

The normal rate of hematocrit (total volume of RBC occupied in blood) is . . .

Adult females - 38-46% (42% in the average) Adult males - 40-54 % (47% average)

What happens if someone who has Type A blood, gets a transfusion from someone who has Type B blood?

Agglutination - clumping of microorganisms or blood cells, typically do to an antigen-antibody reaction. When these antigen-antibody complexes form, they activate plasma proteins of the complement family (described in Section 22.6). In essence, complement molecules make the plasma membrane of the donated RBCs leaky, causing hemolysis (hē-MOL-i-sis) or rupture of the RBCs and the release of hemoglobin into the blood plasma. The liberated hemoglobin may cause kidney damage by clogging the filtration membranes. Although quite rare, it is possible for the viruses that cause AIDS and hepatitis B and C to be transmitted through transfusion of contaminated blood products.

Blood Plasma consist of mostly water (91.5%) and protein solutes. What are the three important protein solutes in blood plasma?

Albumins Globulins Fibrinogens SN: also contains electrolytes, enzymes, hormones, etc.

pulmonary embolism

An embolus that breaks away from an arterial wall may lodge in a smaller-diameter artery downstream and block blood flow to a vital organ. When an embolus lodges in the lungs, the condition is called

RBC Life Cycle - Ferritin

An iron storage protein used in formation of red blood cells

A drop in hematocrit indicates what blood disorder?

Anemia - a lower than normal Red blood cell count

What happens to Red Bone Marrow as we age?

As we age, red marrow turns into yellow marrow, which consist of fat cells. This decreases the amount of red blood cells produced. If we begin to suffer from severe bleeding, our yellow marrow can revert back to red marrow so that more rbc can be produced (clotting)

Lymphocytes

B Lymphocytes, T Lymphocytes, and Natural Killer Cells. B-Lymphocytes (B-Cells) - inactive microbes toxins T-lymphocytes (T-cells) - attack viruses, fungi, transplanted cells, cancer cells, etc. responsible for transfusion reactions, allergies, and rejection of transplanted organs. Natural killer cells - tumor cells

ABO groups

Based off two glycoprotein antigens AB Type A - A antigen Type B - B antigen Type AB - Both A + B antigen Type O - No Antigen

Why do new borns suffer from anemia?

Because their liver, not kidneys (where normal erythropoiesis occurs) produce most erythropoietin. The liver is not sensitive to hypoxia (low o2 concentration in blood), so it doesn't produce RBC's when needed.

Why are granular cells called granular cells?

Because they have cytoplasmic granules that are visible through light microscope after being stained. Agranular leukocytes cannot be seen when stained or viewed under a microscope.

Describe the shape of a red blood cell

Bioncave disc - allows for greater surface area for diffusion of gas molecules into and out of Red Blood cell.

Blood Doping

Blood doping is the increasing of Red Blood cells in order to increase oxygen carrying capacity in the body. Drugs like Procrit and Epogen are used to treat anemia, but some use it to increase rbc count just to gain athletic gain. This can lead to high blood pressure and can make the heart pump harder than normal. This can also increase risk of stroke.

Bone marrow examination

Bone marrow examination is done to test for certain blood disorders such as leukemia or severe anemias. Bone Marrow Aspiration - withdrawal of a small amount of red bone marrow with a fine needle or syringe Bone marrow biopsy - removal of a core of red bone marrow with larger needle

The chemical attraction of WBC's to disease or injury site is termed

Chemotaxis Common stimuli include: toxins released by microbes kinins - product of damage tissue cells Colony stimulating factors (CSF)

What is Leukopenia?

Decrease in white blood cell count. Never beneficial. Common causes include: radiation, shock, and certain chemotherapeutic agents (usually with cancer patients)

Basophils

Develop into mast cells Mast cells liberate heparin, histamine, and serotonin in allergic reactions that "INTENSIFY" the inflammatory response.

Fibrinolytic system

Dissolves small, inappropriate clots; it also dissolves clots at a site of damage once the damage is repaired. Fibrinolysis - dissolution of clots whenever we do not need them.

What is the importance of emigration, chemotaxis, and phagocytosis in fighting bacterial invaders?

Emigration - the process in which white blood cells leave the blood stream and attack foreign invaders in the body. Selectin on endothelial lining of blood vessels attach to intergrin on neutrophils that help lead those WBC's to damaged tissue area. Chemotaxis - is the stimulus the attract white blood cells to foreign pathogen. These include toxins released by microbe, kinin (product of damage tissue), etc. Phagocytosis - the ingestion of microbes (typically by neutrophils and monocytes/macrophages.)

Describe the process of emigration, how does it work?

Emigration is the process in which white blood cells leave the blood stream in order to combat areas of inflammation or infection in the body. When a certain area of the body is infected, endothelial cells display adhesion molecules called "SELECTINS" in response to injury. This cause the lining of blood vessels to stick to the carbohydrates of neutrophils, causing them to slow down and roll along the endothelium lining. On the surface of neutrophils, adhesion molecules called "INTERGRINS" help tether neutrophils to lining of blood vessels and into interstitial fluid of injured tissue.

Erythropoietin

Erythropoietin is a hemopoietic growth factor that increases the number of red blood cell pre cursors.

Erythropoietin - Where is it produced?

Erythropoietin, the hemopoietic growth hormone that regulates the amount of red blood cell precursors , is produced in the kidneys. If kidneys get damaged, RBC count can decrease, leading to low O2 transport in the body.

RBC Life Cycle - After Fe+3 attaches to transferrin, what happens next?

Fe+3 detaches from transferrin and attaches to ferritin, a iron storage protein

RBC Life Cycle - Once Fe+3 reattaches to transferrin (2nd time), what happens to iron molecule?

Fe+3 is transported to Red Bone Marrow. Inside red bone marrow, RBC precursors are taking up for hemoglobin synthesis. Iron is used for heme portion, amino acid is used for globin portion. Erythropoiesis occurs (production of rbc).

Formed Elements, What are they?

Formed elements is the other 45% of blood. It consist of three main parts: Erythrocytes - Red Blood Cells Leukocytes - White blood cells Thrombocytes - Platlets

How many oxygen groups can be on one single hemoglobin molecule

Four - one on each peptide chain (2 alpha + 2 beta).

How are Leukocytosis and Leukopenia different?

Leukocytosis is the increase of white blood cells, which is usually the result of acute infection Leukopenia is the decrease in white blood cells. This is due to things such as radiation or chemotherapy.

Hypoxia - What is it?

Low Oxygen deficiency in the blood. Hypoxia may be due to being a high altitudes where there is low O2 concentration, anemia (low production of red blood cells), etc.

Lymphoid stem cells give rise to..

Lymphocytes - T lymphocytes, b-lymphocytes, natural killer cells.

Agranular leukocytes include

Lymphocytes - stain dark and is round/slightly indented. cytoplasm stain sky blue and form rim around nucleus. Increase in the number of large lymphocytes has diagnostic significance of acute viral infections and immunodeficiency disease. monocytes - kidney shaped, cytoplasm blue-gray, foamy appearance (azurophilic granules = lysosomes) Differentiate into macrophages.

What chemical(s) does neutrophils release in order to destroy foreign pathogens

Lysozomes - which is found in tears, sweat and saliva. Defensin - provides a broad range of antibiotic activity against bacteria and fungi. they poke holes in microbe membranes, resulting in death of foreign pathogen.

White blood cells and other nucleated cells in the body have proteins called ____________________ protruding from their plasma membrane into the extracellular fluid. These act as "cell identity markers".

Major Histocompatibility Complex (MHC) antigens

Blood Volume in Males vs. Females

Males - 5 to 6 liters of blood Females - 4 to 5 liters of blood

Pluripotent cells are derived from..?

Mesenchyme cells (origin of all connective tissue cells)

What are selectins?

Selectins - adhesion molecules on the lining of blood vessels that stick to carbohydrates on the surface of neutrophils to help guide them through interstitial fluid to infected area.

When blood drawn out of a blood vessel, it condenses into two layers, a liquid layer, and a gel layer. What are these two layers called?

Serum - liquid portion (plasma) Clot - gel consisting of a network of insoluble protein fibers called fibrin, in which formed elements of blood are trapped.

Some myeloid cells can differentiate into Progenitor cells. Describe CFU-E, CFU-Meg and CFU-Gm are and what they eventually give rise to?

The CFU's are just another way of describing progenitor cells. CFU-E stands for "Erythrocytes" which give rise to red blood cells. CFU-Meg stands for "Megakaryocytes" - platlets CFU-GM produces granulocytes - neutrophil and monocytes

Why do men have a higher hematocrit volume than females?

The Hormone testosterone (which is more present in males than females) produces more erythropoietin, a hormone used to stimulate the growth of RBCs

RECEPTOR in Erythropoiesis? (Location)

The kidney

RBC life cycle - After erythropoiesis occurs in Red bone marrow, what happens to the non iron portion of heme

The non portion part of heme is converted to biliverdin (green pigment) and bilirubin (yellow pigment). Once biliverdin enters blood stream, it goes to the liver.

Hemopoiesis

The process by which formed elements (RBC, WBC, platelets) of blood is developed

What is Emigration?

The process in which White blood cells leaves the bloodstream in order to phagocytize foreign pathogens/microbes.

the red bone marrow from the donor is taken from what part of the body?

The red bone marrow from a donor is usually removed from the iliac crest of the hip bone under general anesthesia with a syringe and is then injected into the recipient's vein, much like a blood transfusion.

What is the function of electrolytes in Blood Plasma?

They aid in maintaining osmotic pressure, for exchange of gases between blood capillaries.

Thromobopoietin - Where is it produced?

Thrombopoietin, a hemopoietic growth factor that gives rise to platlets, is produced in the liver.

Thrombopoietin

Thromobopoietin is a hemopoietic growth factor that regulates the amount of platelet precursors (Megakaryocytes).

RBC Life Cycle - Once the heme portion of hemoglobin is detached from the red blood cell, It attaches to which plasma protein and why?

Transferrin - Once heme separates from globin, the iron from heme is in form of Fe+3, which attaches to transferrin in order to transport through the blood stream

RBC Life Cycle - Transferrin

Transferrin - transporter of Fe+3 through the blood stream

Which Antigen does each ABO group Have?

Type A - B antibodies Type B - A antibodies Type AB - no antibodies Type O - both A & B antibodies

Universal Donors

Type O blood

RBC life cycle - Once biliverdin enters the liver, it goes to the large intestine and is converted to __________ by bacteria

Urobilinogen

Withdrawing Blood: What is the most common method used to withdraw blood?

Venipuncture - withdrawal of blood from a vein using a needle and collecting tube. a torniquet is wrapped around the arm above the venipuncture site, which causes blood to accumu

Common Pathway

WHAT HAPPENS: 1. Prothrombinase (an enzyme produced in intrinsic or extrinsic pathway) with the help of calcium converts prothrombin into thrombin. 2. Thrombin is converted into soluble fibrinogen then its converted into insoluble fibrin. Thrombin activates factor XIII (fibrin stabilizing factor) The more thrombin created, it used to create fibrin (clotting factor in blood) = prevention of blood loss.

Vascular Spasm

When arteries become damaged, blood vessels begin to constrict (become narrower) to prevent blood loss. This helps reduce loss of blood until the other mechanisms for hemostasis kick in later.

Embolus

blood clot, bubble of air, fat from broken bones, or a piece of debris transported by the bloodstream

What is the function of the enzyme carbonic anhydrase (CA) In hemoglobin (in rbc's).

converts CO2 and water into carbonic acid. Significant: allows for better transport of CO2 in blood plasma when its in the form of carbonic acid. Also aids as a great buffer.

What is a differential white blood cell count?

its a count of the five different white blood cells to detect infection or inflammation, possible effects of poisoning by chemicals or drugs, monitor blood disorders, and effects of chemotherapy.

Erythropoiesis

production of red blood cells in red bone marrow from precursor red blood cells called erythroblast.

Cytokines

small glycoproteins that stimulates proliferation of progenitor cells involved in nonspecific defense (phagocytes), and immune responses (B + T cells). Two important families of cytokines include CSF (colony stimulating factors) and interleukins.

RBC Life Cycle - Most of uroblinogen is eliminated as feces as brown pigment called ______________

stercobilin.

Clotting an undamaged blood vessel (usually a vein) is a process called?

thrombosis

RBC Life Cycle - Some of Urobilinogen is converted to _____________ once it reaches the blood stream

urobilin (excreted as urine)

STIMULUS in Erythropoiesis?

Hypoxia - low o2 concentration in the blood

What is the primary site of hemopoiesis?

RED BONE MARROW - a highly vascularized connective tissue located between trabeculae of "spongy bone tissue". Present in axial skeleton, pectoral and pelvic girdles, epiphysis of the humerus and femur.

RH Blood Group

RH Positive - RH antigen RH Negative - No RH antigen (rare) If a person that is RH negative is exposed to someone who is RH positive, antibodies are formed but most of the time, nothing bad happens due to the immune response. Once you are exposed one time, you body begins to make antibodies. If a pregnant woman is pregnant and is RH -, and her baby is RH +, the blood from the baby can leak through the placenta and mix with mother's blood, if this happens the first time, nothing happens But if the mother has a second child, who is also RH -, this could lead to complications, because those antibodies made previously could attack the baby! This is due to antigen-antibody reaction causing agglutination (blood clumping) and hemolysis of the baby's rbcs. The result is Hemolytic Disease of the NewBorn (HDN).

Which ones are more numerous: RBC or WBC?

Red Blood Cells

Formed Elements is composed of what three things?

Red Blood cells (gives formed elements red color), also known as erythrocytes White blood cells, also known as leukocytes Platelets, also known as thrombocytes (blood clotting).

Myeloid stem cells give rise to...

Red blood cells Platelets monocytes neutrophils eosinophils basophils mast cells

What is the function of CO2 in blood plasma

Regulation of blood pH (buffer system)

What is Red Bone Marrow Transplant?

Replacement of cancerous red bone marrow cells. This is usually done by chemo, where radiation kills off all cancerous cells before replacement.

Erythroblast divide and proliferate into _________ , which loses its nucleus, causing the cell to indent and have characteristic bioncave shape

Reticulocytes - mature into red blood cells within 1-2 days after leaving red bone marrow

Extrinsic Pathway - Describe whats going on

-Shorter than the intrinsic pathway 1. Tissue Factor (known as thromboplastin) leaks from the "exterior" part of the blood vessel. 2. Tissue Factor (thromboplastin) activates "clotting factor x" (with the help of Calcium). 3. Clotting factor x then activates clotting factor v. Clotting factor v + x combine with calcium to produce prothrombinase.

Red Blood Cell Life Cycle - STEPS

1. Macrophages in the spleen, liver or red bone marrow phagocytize ruptured red blood cells. 2. The globin (small glycoprotein) and heme (iron containing group) split 3. Globin is broken down into amino acids (reused for production of other proteins) 4. Iron is removed from Heme group, as Fe+3,, and attaches to transferrin - a transporter for Fe+3 in the blood 5. Fe+3 detaches from transferrin, and attaches to ferrtin (storage protein) 6. Fe+3 detaches from ferritin, and re-attaches to transferrin 7. The Fe+3-transferrin complex is carried to Red Bone marrow., where red blood cell precursor cells (proethyroblasts) take it up through endocytosis for the use of hemoglobin synthesis. Iron is needed for heme portion and amimo acid is needed for globin portion. Vitamin B12 is needed for hemoglobin synthesis. 8. Erythropoiesis in red bone marrow result in red blood cells that enter circulation 9. When iron is removed from Heme, the non iron portion of heme is converted to biliverdin (green pigment) then into bilirubin (yellow). 10. Bilirubin is transported to liver 11. Within the liver, bilirubin is released by liver cells into bile, passing into small intestine then to large intestine 12. In large intestine, bacteria converts bilirubin into urobilinogen. 13. Some Urobilinogen is converted into yellow pigment called urobilin, excreted in urine. 14. Most uroblinogen is released and eliminated in feces in form of brown pigment called stercobiin (gives feces brown color)

RBC Life Cycle - Describe steps 1-3 in your own terms.

1. Macrophages in the spleen, liver or red bone marrow phagocytize worn out red blood cells. 2-3. The globin (glycoprotein part) is broken from the heme portion (iron containing part). Globin is broken down into amino acids which is used for protein synthesis.

Steps for Plug formation of platelets

1. Platelet adhesion - when platelets attach to endothelium wall of blood vessels (connective tissue of endothelium). 2. Platelet release reaction - Once platelets attach to damaged blood vessels, they begin a chain of reactions. ADP and Thromboxane activate platelet formation. Serotonin and Thromboxane A2 begin to contraction of smooth muscle fibers on blood vessels (reducing blood flow to damage tissue) 3. Platelet Aggregation: ADP causes platelets to become more sticky, causing a greater accumulation of platelets at the damaged tissue. This is called the platelet plug

what are some draw backs to red bone marrow transplants?

1. Since the recipient's white blood cells have been completely destroyed by chemotherapy and radiation, the patient is extremely vulnerable to infection. (It takes about 2-3 weeks for transplanted bone marrow to produce enough white blood cells to protect against infection.) 2. transplanted red bone marrow may produce T cells that attack the recipient's tissues, a reaction called graft-versus-host disease. Similarly, any of the recipient's T cells that survived the chemotherapy and radiation can attack donor transplant cells. 3. Another drawback is that patients must take immunosuppressive drugs for life. Because these drugs reduce the level of immune system activity, they increase the risk of infection. Immunosuppressive drugs also have side effects such as fever, muscle aches, headache, nausea, fatigue, depression, high blood pressure, and kidney and liver damage.

Three Mechanism(s) to reduce blood loss?

1. Vascular Spasm - smooth muscle of a blood vessel wall contracts (becomes more narrow) to stop bleeding 2. Platelet Plug formation - clumping of platelets around the damage to stop bleeding 3. blood clotting (coagulation)

Color of Blood

Color of Blood (Red) varies due to amount of Oxygen concentration. Saturated with O2 - bright red Unsaturated with O2 - dark red

Eosinophils

Combat the effects of histamine in allergic reactions, phagocytize antigen-antibody complexes and combat parasitic worms.

White blood cells can be classified into what two categories

Granular and agranular

What is the main stimulus for erythropoiesis?

Hypoxia - low concentration of O2 in the blood. This stimulates the kidneys to release Erythropoietin (hemopoietic growth factor) that stimulates production of red blood cells. More RBC = more oxygen.

The percentage of total blood volume occupied in RBC is called the ________________

Hematocrit

What is the importance of the Heme group in hemoglobin?

Heme contains a Fe+2 iron molecule on it that reversibly binds to oxygen.

Describe the hemoglobin structure in RBC

Hemoglobin is composed of a protein called globin. Globin has 4 peptide chains (2 alpha and 2 beta) Each peptide chain has a heme group on it

In Red Blood Cells, what gives them their red color?

Hemoglobin.

The main goal of hemostasis is to prevent what?

Hemorrhages - the large loss of blood from blood vessels.

What is Hemostasis?

Hemostasis is the process in which our body stops blood loss

EFFECTOR in Erythropoiesis

Increase in EPO increases the amount of red blood cells produced, RESULTING in more oxygenated blood.

What is Leukocytosis?

Increase in White Blood cells. This usually occurs due to stresses caused by foreign microbes/pathogens that enter the body (normal response). Above 10,000/uL

What are intergrins?

Intergrins - adhesion molecules that line wall of neutrophils that help stick to endothelium lining (blood vessels) in order to reach damaged tissue cells.

What is a Cord blood transplant?

Is when stem cells from the umbilical cord are removed from a syringe and then frozen (for red blood cell production). It has advantages over red bone marrow transplants 1. Easily collected using syringe and frozen 2. less likely to cause graft vs. host disease - attack of its own tissue from T-Cells 3. More abundant 4. Can be stored 5. Cause less infection.

RBC Life Cycle - Once Fe+3 is released by ferritin (iron storage protein), what happens next in the cycle.

It reattaches to transferrin (iron transporter protein)

CONTROL CENTER in Erythropoiesis

Kidney releases EPO (Erythropoietin) - a hormone that stimulates production erythroblast into reticulocytes faster

Precursor cells

Known as "blast" - actually develop into actual formed elements of the blood

In hemopoiesis, pluripotent stem cells in red bone marrow breaks off and produce which two stem cells?

Myeloid stem cells Lymphoid stem cells

These White blood cells respond the quickest to the site of infection.

Neutrophils

There are five known WBC's stated in this text, what are they?

Neutrophils Basophils Eosinophils Lymphocytes Monocytes

Granular leukocytes include which three leukocytes?

Neutrophils - smallest, evenly distributed and pale lilac (color). Neutrophilic (doesn't attract acid or basic colors when stained), nucleus 2-5 lobes. As cell ages, lobes increases. Many differently shaped lobes are known as polymorphonuclear leukocytes. Basophils - stain blue when stained (baso = basic loving). granules obscured with nucleus, has two lobes Eosinophils - stain red-orange with acid dye. granules do not cover or obscure nucleus. two lobes.

Hemoglobin also regulates blood flow and pressure. What gaseous hormone regulates blood flow and pressure in hemoglobin?

Nitric Oxide (NO). Nitric oxide increases "vasodilation", increase in blood vessels, that improves blood flow and enhances oxygen delivery to cells.

Unlike Red Blood cells, White Blood Cells have what?

Nucleus + organelles. They do not have hemoglobin

Universal recipients

People who are TYPE AB are universal recipients because they do not have either Type a or B antibodies.

WBC's, specifically Neutrophils and macrophages, are active in what process? Describe what this process is?

Phagocytosis - the ingestion of bacteria and dispose of dead matter.

Plasminogen

Plasminogen is an enzyme that is converted to plasmin and promotes fibrinolysis (dissolution of clots when not needed). Plasminogen is converted to plasmin by thrombin, activated factor XII, and tissue plasminogen activator (t-PA), which is synthesized in endothelial cells of most tissues and liberated into the blood.

When Red blood cell count is too High, what is that called?

Polycythemia (65% and higher) - makes blood more hard to pump through the heart, increases high blood pressure, increased risk of stroke.

Anticoagulants

Prevent, delay the amount of blood clotting occurring in blood