AP 2 - Blood (Dr. Chinnery)

Define hematocrit

- % of blood volume composed of RBCs

Female Hematocrit (average value)

- 38 - 46 % in women

Male Hematocrit (average value)

- 40 - 54 % in men (due to inc. testosterone)

Describe the physical characteristics of blood

- More viscous than water - 100.4 degrees F - pH 7.4 (ph 7.35 - 7.45) - 4 - 5 Liters (adult men 5-6 L, adult women 4-5 L)

Given a person's specific blood type, be able to predict the blood types of people who can receive the person's blood and the blood types of people who can donate blood to that person.

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Name the 2 fluids that service the cells of the body

1) Blood 2) Interstitial fluid/ extracellular fluid *O2, nutrients, hormones, and wastes are exchanged between these 2 fluids

Name the 4 major components of blood

1) Plasma 2) Red Blood Cells (RBC) 3) White Blood Cells (WBC) 4) Platelets •About 55% of the volume of blood is plasma and 45% of the volume is the three blood cells

Functions of blood

1) transportation 2) protection (from disease & blood loss) 3) regulation (ph & body temperature)

Briefly describe the process by which red blood cells, white blood cells, and platelets are formed. Be sure to include hemocytoblasts, myeloid stem cells, lymphoid stem cells, growth factors, reticulocytes, and erythropoietin

1. All formed elements arise from stem cells of the red bone marrow. 2. One step lower on the hierarchy of stem cells is the hemocytoblast (baby blood cell). 3. This then splits into the myeloid stem cells and lymphoid stem cells. Lymphoid stem cells - give rise to lymphocytes Myeloid stem cells - give rise to all other blood cells and platelets. (SEE "CELL FAMILY TREE" DIAGRAM FOR BETTER DETAILS)

What are the 3 steps of the platelet plug formation?

1. Platelet Adhesion 2. Platelet Release Reaction 3. Platelet Aggregation

Compare a thrombosis to an embolus

1. Thrombosis Is a clot forming in an unbroken blood vessel 2. Embolus Is a free floating clot in the blood that may cause strokes and myocardial infarctions; low dose aspirin blocks synthesis of thromboxan A2 and reduces inappropriate clot formation.

Name the components that make up plasma

1. Water 2. Proteins

Platelet counts

150,000-400,000/mm3

WBC counts

5,000 to 10,000 per cubic mm

State the percentage of the formed elements that are RBCs

99%

Identify the factors that determine a person's blood type

A person's blood type is checked before an individual gives or receives blood. Blood types are based on the presence or absence of certain protein molecules called antigens.

Describe the functions of each of the proteins found in plasma

Albumins - major component of osmotic pressure of plasma Globulins - antibodies (immunoglobulin) & transport proteins Fibrinogens - functions in blood clotting Regulatory Proteins - enzymes involved in the chemical reactions that occur in the blood and hormones that are being transported throughout the body to their target cells

Define anemia

An abnormally low red blood cell count Anemia results in the inability of the blood to carry and deliver sufficient oxygen to the body cells. Symptoms include general fatigue, shortness of breath, and premature muscle fatigue.

State the type of tissue blood is classified and explain why

Blood is a CONNECTIVE tissue 1. because it contains cells (WBC, RBC, Platelets) 2. protein fibers (proteins are converted to fibers) 3. ground substance (plasma).

Describe regulation in blood

Buffers in the blood stabilize the pH of the fluid surrounding cells (extracellular fluid). Blood vessels in the skin are dilated (relaxed) or constricted so that heat from the blood can be given off or conserved.

clots retraction

Clot retraction follows minutes after the clotting cascade. The clot plugs ruptured area of blood vessel; platelets pull on fibrin threads causing clot retraction and expelling serum; edges of damaged vessel are pulled together and endothelial cells repair the blood vessel.

Vascular Spasm (Vasoconstriction)

Cutting the wall of a blood vessel triggers pain receptors. Reflex vasoconstriction of small blood vessels and arterioles can reduce blood loss for several hours until other mechanisms can take over. Chemical agents such as serotonin are involved.

Describe how clots are dissolved and how clots that are not appropriate are prevented

Factor XII / Hageman's factor converts inactive plasminogen in plasma to plasmin which dissolves fibrin threads once tissue repair is completed. Fibrinolytic system dissolves small, inappropriate clots. clot prevention in vessels involves heparin from basophil which acts as an anticoagulant. Other agents involved in preventing unwanted clots are tissue plasminogen activator (tPA) and antithrombin III.

Describe the structure of hemoglobin

Globin is composed of 4 polypeptide chains Heme pigment is bonded to each globin chain one Fe+2 ion attached to each heme (so 4 Fe+2 per hemoglobin). Each Fe+2 can combine reversibly with 1 O2 molecule. Thus 1 hemoglobin can carry 4 molecules of O2

Classify the 2 types of WBCs as either granulocytes or agranulocytes

Granulocytes = Nuetrophils, Eosinophils, Basophils ( "-phils") Agranulocytes = Lymphocyte, Monocyte

Name the process in which blood loss is prevented when a blood vessel wall is damaged

Hemostasis

State the general function of WBC's

Involved in fighting infections

Give the functions of each major type of white blood cell

Neautrophil - Destroy bacteria by phagocytosis Lymphocyte - Mount immune response by direct cell attack (T cells) or via antibodies (B cells) Monocyte - Phagocytosis: Differentiates into macrophages and dendritic cells in response to inflammation Eosinophil - turn off allergic responses and releases toxins that kill bacteria and parasites but also causes tissue damage Basophil - Responsible for defense against parasites. Releases histamines that cause inflammation and may be responsible for allergic reactions

Name the five types of leukocytes (white blood cells)

Never Let Monkeys Eat Bananas Nuetrophil Lymphocyte Monocyte Eosinophil Basophil

List the 5 types of WBCs from most abundant to least abundant

Never Let Monkeys Eat Bananas - Neutrophils, Lymphocyte, Monocyte, Eosinophil, Basophil

Give examples of nutrients found in plasma

Nutrients absorbed from the gut or from other organs of origin are carried in the plasma, such as glucose, fats, amino acids, minerals, and vitamins.

State the percentage of WBCs found circulating in the blood at any one time

Only 2% of total WBC population is in circulating blood at any given time. The rest are in the lymphatic fluid, skin, lungs, lymph nodes, and spleen.

Give examples of waste products found in plasma

Other proteins wastes such as urea and bilirubin also found

Describe the structure of thrombocytes (platelets)

Platelets have no cell nucleus: they are fragments of cytoplasm that are derived from the megakaryocytes of the bone marrow, and then enter the circulation.

State the lifespan of RBCs and platelets, and life span of WBCs

RBC's lifespan - 120 days Platelets - 8-9 days WBC's - 13 - 20 days

Compare the structure of adult vs. fetal hemoglobin

Structurally, both adult and fetal hemoglobin are tetramers containing four protein subunits. Adults have 2 beta and 2 alpha, while fetal have 2 alpha and 2 gamma subunits. This allows the fetal hemoglobin to have an affinity to oxygen

Describe transportation in blood

The blood transports heat, dissolved gases, nutrients, hormones, and metabolic wastes • Blood picks up O2 from the lungs and drops off CO2. • Blood picks up nutrients from the digestive tract. • Blood picks up hormones from endocrine glands. • Blood picks up wastes and carries it to the kidneys, lungs, and other organs of excretion

Describe the general functions of each of the common electrolytes found in plasma

The electrolytes in plasma include • Na+ - nerve impulses • K+- nerve impulses • Ca2+- muscle contraction, bone & teeth structure, cell signaling, etc • Cl— maintain negative conc. inside cell • HCO3— acts as buffer (maintains pH) • and others.

Describe the function of platelets

To facilitate blood clotting - the purpose of which is to prevent loss of body fluids

Determine the antigen(s) and antibodies present in a given blood type

Type A: A person with type A blood has A antigens on the surface of his or her red blood cells and B antibodies in his or her blood plasma. Type B: A person with type B blood has B antigens on the surface of his or her red blood cells and A antibodies in his or her blood plasma. Type AB: A person with type AB blood has both A and B antigens on the surface of his or her red blood cells and no A or B antibodies in his or her blood plasma. Type O: A person with type O blood has neither A nor B antigens on the surface of his or her red blood cells and both A or B antibodies in his or her blood plasma.

Describe the appearance of white blood cells when viewed through a microscope

WBC are larger and circular and contain nuclei (unlike RBC). The nuclei each have unique shapes based on the type of WBC it is.

Describe how RBCs are recycled

Worn out cells are removed by fixed macrophages in the spleen and liver. The RBCs are broken down and the components are recycled: a. Globin is broken down into amino acids and used to create new proteins b. Heme is split into iron (Fe+2) to be used in bone marrow for hemoglobin synthesis and into biliverdin (green) which is converted to bilirubin (yellow). Bilirubin is secreted by the liver into bile and is excreted in feces and urine)

Give the function of hemoglobin

a protein that transports primarily oxygen but also some carbon dioxide.

Name the proteins found in plasma

a. Albumins b. Globulins c. Fibrinogens d. Regulatory proteins

Define the term hemophilia

an inherited deficiency of clotting factors. Bleeding occurs spontaneously or after minor trauma. Treatment is transfusions of fresh plasma or concentrates of whatever clotting factor the person is unable to make.

hemo

blood (hemoglobin)

Name the location in which blood cells are formed

bone marrow

-cytes

cells

Describe the structure of mature red blood cells, including their shape, presence or absence of organelles, presence of hemoglobin, etc.

flexible, biconcave cells without a nucleus, without many organelles, and filled with hemoglobin.

-poiesis

formation, production

Coagulation or clotting

is the transformation of blood from a liquid into a solid gel. Formation of a clot on top of the platelet plug strengthens and supports the plug, reinforcing the seal over a break in a vessel. The ultimate step in clotting is the conversion of a large, soluble protein made in the liver called fibrinogen to an insoluble, threadlike protein called fibrin. This is catalyzed by the enzyme called thrombin. Other substances required for clotting are Ca2+, 12 enzymes synthesized by liver cells called clotting factors and substances released by platelets or damaged tissues.

Give examples of gases found in plasma

oxygen, carbon dioxide

platelet aggregation

property of platelets to adhere to an injured surface and then attract other platelets, which clump together or aggregate at the area, plugging up an injury to the vascular system

erythros

red; erythrocytes

Name common electrolytes found in plasma

sodium (most abundant), potassium, calcium, chloride, magnesium, and bicarbonate

Describe the major function of mature red blood cells

to transport oxygen to body cells and deliver carbon dioxide to the lungs

Define polycythemia

too many RBCs (over 50%). Caused by dehydration, tissue hypoxia, high altitude, blood doping in athletes

Identify which of the components of plasma makes up 92% of the plasma

water

leukos

white (leukocyte)

chronic leukemia

• Is accumulation of mature WBCs in bloodstream because they do not die.

acute leukemia

• Is uncontrolled production of immature WBC's • This crowds out normal red bone marrow cells and prevents the production of RBC's and platelets

platelet release reaction

• Platelets activated by adhesion, release ADP and thromboxane A2. • These chemicals work together to activate other platelets just passing by.

Describe protection in blood

• Protects against fluid loss through damaged vessels. Platelets in the blood and clotting proteins minimize blood loss when a blood vessel is damaged. • Protects against pathogens and toxins. White blood cells (leukocytes) in the blood help defend against infection

common pathway

• Prothrombin is converted to thrombin. • Thrombin in the presence of Ca2+ converts soluble fibrinogen to insoluble fibrin threads. • Thrombin then activates fibrin stabilizing factor XIII (which will stabilize the fibrin clot and makes it insoluble.)

platelet adhesion

• The membranes of the cells that line the inside of the damaged blood vessel become sticky when collagen protein fibers are exposed. • Platelets are attracted to the collagen protein fibers.

Instrinsic pathway

• This pathway involves 7 separate steps and begins when damage to blood vessel wall activates the clotting factor called Factor XII (Hageman factor).

extrinsic pathway

• This pathway takes a shortcut and requires only 4 steps and begins when blood has escaped into the tissues. • Damaged tissues leak thromboplastin into the bloodstream which then activates Factor X. • Factor X catalyzes the conversion of prothrombin into thrombin.