Question | Answer |
Blood: a fluid connective tissue composed of | Plasma :liquid portion |
Erythrocytes | Red Blood Cells |
Leukocytes | White Blood Cells |
Hematocrit | Percent of blood volume that is RBCs |
what is the percentage of RBC in Males | 47% |
what is the percentage of RBC in Females | 42% |
Physical Characteristics of blood | Sticky, opaque fluid
Color scarlet to dark red
pH 7.35–7.45 |
Tempature of blood and percentage of body weight ? | 38 C and 8 % of body weight |
Average volume of blood in males and females ? | Males 5-6 L and Females 4-5 L |
What are the functions of blood ? | Distribution of blood
O2 and nutrients to body cells
Metabolic wastes to the lungs and kidneys for elimination
Hormones from endocrine organs to target organs |
What are blood regulations ? | Regulation of blood
Body temperature by absorbing and distributing heat
Normal pH using buffers
Adequate fluid volume in the circulatory system |
What does blood protect ? | Protection against
Blood loss
Plasma proteins and platelets initiate clot formation
Infection
Antibodies
Complement proteins
WBCs defend against foreign invaders |
What is 90% of water and its
Proteins are mostly produced by the liver & are the most abundant solutes ( 8% by wt ) in the plasma. | Blood Plasma |
What is the percentage of albumin in blood plasma ? | 60% |
Blood plasma has _________ _________of metabolism—lactic acid, urea, creatinine | Nitrogenous by-products |
Blood Plasma has ____________—glucose, carbohydrates, amino acids
Electrolytes—Na+, K+, Ca2+, Cl–, HCO3–
Respiratory gases—O2 and CO2
Hormones | Nutrients |
Only _______are complete cells | White Blood Cells |
_________have no nuclei or organelles | Red Blood Cells |
__________are cell fragments | Platelets |
Most blood cells originate in what and do not divide ? | Bone Marrow |
What are biconcave discs, anucleate, essentially no organelles and
Filled with hemoglobin (Hb) for gas transport | Erythrocytes |
Erythrocytes contain the plasma membrane protein _______and other proteins,Which Provide flexibility to change shape as necessary. | spectrin |
Erythrocytes are the major factor contributing to | blood viscosity |
Structural characteristics contribute to gas transport
Biconcave shape—huge surface area relative to volume
>97% hemoglobin (not counting water) | Erythrocytes |
What are the fuctions of Erythocytes ? | RBCs are dedicated to respiratory gas transport |
Hemoglobin binds reversibly with what ? | Oxygen |
What is the hemoglobin structure of Erythocytes ? | Protein globin: two alpha and two beta chains
Heme pigment bonded to each globin chain |
Each Hb molecule can transport | four O2 and 1 billion RBC |
O2 loading in the lungs
Produces what ? | Oxyhemoglobin (Ruby red) |
O2 unloading in the tissues produces what ? | deoxyhemoglobin or reduced hemoglobin (dark red) |
CO2 loading in the tissues Produces _____________(carries 20% of CO2 in the blood) | carbaminohemoglobin |
What is the process of blood cell formation and
Occurs in red bone marrow of axial skeleton, girdles and proximal epiphyses of humerus and femur | Hematopoiesis |
What gives rise to all formed elements
Hormones and growth factors push the cell toward a specific pathway of blood cell development | Hemocytoblasts |
red blood cell production is known as | Erythropoiesis |
A hemocytoblast is transformed into a | proerythroblast |
Proerythroblasts develop into early | early erythroblasts |
Erythropoiesis phases in development | 1.Ribosome synthesis
2.Hemoglobin accumulation
3.Ejection of the nucleus and formation of reticulocytes |
Too few RBCs leads to | tissue hypoxia |
Too many RBCs increases | blood viscosity |
Balance between RBC production and destruction depends on | Hormonal controls
Adequate supplies of iron, amino acids, and B vitamins |
This substance is a direct stimulus for erythropoiesis
Released by the kidneys in response to hypoxia ? | Erythropoietin |
Causes of hypoxia | Hemorrhage or increased RBC destruction reduces RBC numbers
Insufficient hemoglobin (e.g., iron deficiency)
Reduced availability of O2 (e.g., high altitudes |
Effects of EPO | More rapid maturation of committed bone marrow cells
Increased circulating reticulocyte count in 1–2 days |
Testosterone also enhances EPO production, resulting in higher ____counts in males | RBC |
Life span of erythocyctes :
Old RBCs become fragile, and Hb begins to degenerate | 100–120 days |
Heme and globin are | Separated |
What is salvaged for reuse ? | Iron |
Heme is degraded to yellow the pigment | bilirubin |
the body in feces as | stercobilin |
Globin is metabolized into | amino acids |
Blood has abnormally low O2-carrying capacity and is accompanied by fatigue, paleness, shortness of breath, and chills is known as ? | Anemia |
Deficiency of vitamin B12
Lack of intrinsic factor needed for absorption of B12
Treated by intramuscular injection of B12 or application of Nascobal | Pernicious anemia |
Absent or faulty globin chain
RBCs are thin, delicate, and deficient in hemoglobin | Thalassemias |
Defective gene codes for abnormal hemoglobin (HbS)
Causes RBCs to become sickle shaped in low-oxygen situations | Sickle-cell anemia |
excess of RBCs that increase blood viscosity | Polycythemia |
Results from:
Polycythemia vera—bone marrow cancer
Secondary polycythemia—when less O2 is available (high altitude) or when EPO production increases
Blood doping | Polycythemia |
What makes up <1% of total blood volume
Can leave capillaries via diapedesis
Move through tissue spaces by ameboid motion and positive chemotaxis | Leukocytes |
what has WBC count over 11,000/mm3
Normal response to bacterial or viral invasion | Leukocytosis |
What are neutrophils, eosinophils, and basophils | Granulocytes |
what has the most numerous WBCs
Polymorphonuclear leukocytes (PMNs)
Fine granules take up both acidic and basic dyes
Give the cytoplasm a lilac color
Granules contain hydrolytic enzymes or defensins
Very phagocytic—“bacteria slayers” | neutrophils |
What is Red-staining, bilobed nuclei
Red to crimson (acidophilic) coarse, lysosome-like granules
Digest parasitic worms that are too large to be phagocytized | eosinophils |
Rarest WBCs
Large, purplish-black (basophilic) granules contain histamine | Basophils |
an inflammatory chemical that acts as a vasodilator and attracts other WBCs to inflamed sites | Histamine |
lymphocytes and monocytes
Lack visible cytoplasmic granules
Have spherical or kidney-shaped nuclei | Agranulocytes |
Large, dark-purple, circular nuclei with a thin rim of blue cytoplasm
Mostly in lymphoid tissue; few circulate in the blood
Crucial to immunity | Lymphocytes |
act against virus-infected cells and tumor cells | T-Cells |
give rise to plasma cells, which produce antibodies | B-Cells |
The largest leukocytes
Abundant pale-blue cytoplasm
Dark purple-staining, U- or kidney-shaped nuclei | Monocyte |
Leave circulation, enter tissues, and differentiate into macrophages | Monocytes |
Actively ________________; crucial against viruses, intracellular bacterial parasites, and chronic infections | phagocytic cells |
Monocytes activate ____________to mount an immune response | lymphocytes |
The Production of WBCs
Stimulated by chemical messengers from bone marrow and mature WBCs | Leukopoiesis |
Abnormally low WBC count—drug induced | Leukopenia |
Bone marrow totally occupied with cancerous leukocytes
Immature nonfunctional WBCs in the bloodstream
Death caused by internal hemorrhage and overwhelming infections | Leukemia |
Small fragments of megakaryocytes
Formation is regulated by thrombopoietin | Platelets |
Form a temporary platelet plug that helps seal breaks in blood vessels
Circulating platelets are kept inactive and mobile by NO and prostacyclin from endothelial cells of blood vessels | Platelets |
Infectious mononucleosis: highly contagious viral disease.
Etiology Epstein-Barr virus.
The hallmark of this disease is excessive numbers of agranulocytes.
Symptoms include fatigue, chronic sore throat, low-grade fever, general malaise. | Mono |
Fast series of reactions for stoppage of bleeding | 1.Vascular spasm
2.Platelet plug formation
3.Coagulation (blood clotting) |
Platelet Plug Formation: Positive Feedback Cycle | At site of blood vessel injury, platelets
Stick to exposed collagen fibers with the help of von Willebrand factor, a plasma protein
Swell, become spiked and sticky, and release chemical messengers |
Normally platelets do not stick together or to | endothelial lining. |
Intact endothelial lining releases __________preventing platelet aggregation. (prostacyclin). | Chemicals |
When endothelial lining is damaged, ___________ are exposed and platelet stick to this tenaciously | collagen fibers |
All blood clotting factors normally circulate in the blood in the | inactive form until mobilized |
A set of reactions in which blood is transformed from a liquid to a gel | Coagulation |
Coagulation reinforces the platelet plug with | fibrin threads |
what are the three phases of coagulation | 1.Prothrombin activator is formed (intrinsic and extrinsic pathways)
2.Prothrombin is converted into thrombin
3.Thrombin catalyzes the soluble fibrinogen into insoluble fibrin mesh. |
Is triggered by negatively charged surfaces (activated platelets, collagen, glass)
Uses factors present within the blood (intrinsic) | Intrinsic pathway |
Is triggered by exposure to tissue factor (TF) or factor III (an extrinsic factor)
Bypasses several steps of the intrinsic pathway, so is faster | Extrinsic pathway |
Prothrombin activator catalyzes the transformation of prothrombin to the active enzyme | thrombin |
Thrombin converts fibrinogen to | fibrin |
Actin and myosin in platelets contract within | 30–60 minutes |
stimulates division of smooth muscle cells and fibroblasts to rebuild blood vessel wall | Platelet-derived growth factor |
stimulates endothelial cells to multiply and restore the endothelial lining | Vascular endothelial growth factor |
Begins within two days
Plasminogen in a clot is converted to
plasmin by tissue plasminogen activator
(tPA), factor XII and thrombin | |
Plasmin is a | fibrin-digesting enzyme |
clot that develops and persists in an unbroken blood vessel
May block circulation, leading to tissue death | Thrombus |
a thrombus freely floating in the blood stream | Embolus |
deficient number of circulating platelets
Petechiae appear due to spontaneous, widespread hemorrhage
Due to suppression or destruction of bone marrow (e.g., malignancy, radiation) | Thrombocytopenia |
Humans have ____ varieties of naturally occurring RBC antigens | 30 |
When serum containing anti-A or anti-B agglutinins (antibodies) is added to blood, agglutination will occur between the agglutinin and the corresponding | agglutinogens(antigens) |