Test 1: Blood, Heart, & Cardiovascular System Flashcards
Blood is made up of the following
- Plasma: Water, Solutes (electrolytes, vitamins, etc), proteins, antigens etc.
- Formed Elements: RBC, WBC, and Platlets
Formed elements in blood
- Erythrocytes (RBC)
- Platelets
- Leukocytes (WBC)- 5 total/ 2 categories:
granulocytes (with granules)
- neutrophils
- eosinophils
- basophils
agranulocytes (without granules)
- lymphocytes
- monocytes
Name these formed elements in blood
A.Monocyte
B.Platelets
C.Small Lymphocyte
D.Neutrophil
E.Large Lymphocyte
F.Basophil
G.Small Lymphocyte
H.Neutrophil
I.Eosinophil
J.Erthyrocyte
K.Young Neutrophil
L.Monocyte
M.Neutrophil
Plasma Components
- Water
- Proteins
- Nutrients
- Electrolytes
- Nitrogenous Waste
- Hormones
- Gases
Plasma Proteins & Function
Formed by the liver (except globulins)
- Albumins: smallest and most abundant
* Contribute to and osmolarity; influence blood pressure, flow, and fluid balance viscosity - Globulins (Antibodies)
- Provide immune system functions
- Alpha, beta, and gamma globulins
- Fibrinogen
* Precursor of fibrin threads that help form blood clots - Haptogloblulin: transports hemoglobin released by dead erthytocytes
- Ceuloplasmin: transports copper
- Prothombin: promotes blood clotting
- Transferrin: transports iron
Plasma Nitrogenous Compounds
–Free amino acids from dietary protein or tissue breakdown
–Nitrogenous wastes (urea)
- Toxic end products of catabolism
- Normally removed by the kidneys
Plasma Nutrients
- Glucose
- Vitamins
- Fats
- Cholesterol
- Phospholipids,
- Minerals
Plasma Electrolytes
- Na+ : makes up 90% of plasma cations
- K+
- Cl-
- Ca2+
Plasma Gases
-Dissolved O2, CO2, and Nitrogen
Erythocyte: Structure & Function
- *Structure:**
- Disc shaped cell with thick rim
–Lose nearly all organelles during development
•Lack mitochondria
- Anaerobic fermentation to produce ATP
•Lack of nucleus and DNA
- No protein synthesis or mitosis
- Blood type determined by surface glycoproteins and glycolipids
•Stretch and bend as squeezed through small capillaries
Cytoskeletal proteins (spectrin and actin) give membrane durability and resilience
Function:
1.Gas Transport
–Carry oxygen from lungs to cell tissues
–Pick up CO_2 from tissues and bring to lungs
Blood Type & How They Are Determined
Antigen (Flags)
Types:
A+
A-
B+
B-
AB+
AB-
O+
O-
Important structural components in Erythrocytes that allow for its function
Important role in gas transport and pH balance
–Increased surface area/volume ratio
- Due to loss of organelles during maturation
- Increases diffusion rate of substances
–33% of cytoplasm is hemoglobin (Hb)
- 280 million hemoglobin molecules on one RBC
- O2 delivery to tissue and CO2 transport to lungs
- Carbonic anhydrase (CAH) in cytoplasm
–Produces carbonic acid from CO_2 and water
Leukocyte: Structure & Function
•Least abundant formed element
»5,000 to 10,000 WBCs/μL
- Protect against infectious microorganisms and other pathogens
- Conspicuous nucleus
- Spend only a few hours in the bloodstream before migrating to connective tissue
- Retain their organelles for protein synthesis
- Granule Presence in some
- All WBCs have lysosomes called nonspecific (azurophilic) granules
- Granulocytes (some WBCs) have specific granules that contain enzymes and other chemicals employed in defense against pathogens
Neutrophil: Stucture & Function
Structure:
–Neutrophils (60% to 70%): polymorphonuclear leukocytes
•Barely visible granules in cytoplasm; three- to five-lobed nucleus
Function:
•aggressively antibacterial
–Neutrophilia—rise in number of neutrophils in response to bacterial infection
Purpose of granulocytes
Contain enzymes and other chemicals employed in defense against pathogens
Eosinophils
Structure:
- Granulocyte
- –(2% to 4%)
•Large rosy-orange granules; bilobed nucleus
Function
•increased numbers in parasitic infections, collagen diseases, allergies, diseases of spleen and CNS
-Phagocytosis of antigen–antibody complexes,
allergens, and inflammatory chemicals
–Release enzymes to destroy large parasites
Basophils: Structure & Function
Structure:
- Granulocyte
- (less than 1%)
•Large, abundant, violet granules (obscure a large S-shaped nucleus)
Function:
- Increased numbers in chickenpox, sinusitis, diabetes
- Secrete histamine (vasodilator): speeds flow of blood to an injured area
- Secrete heparin (anticoagulant): promotes the mobility of other WBCs in the area
Lymphoctes: Structure & Function
Structure:
–(25% to 33%)
•Variable amounts of bluish cytoplasm (scanty to abundant); ovoid/round, uniform dark violet nucleus
Function:
•Lymphocytes—increased numbers in diverse infections and immune responses
–Destroy cells (cancer, foreign, and virally infected cells)
–“Present” antigens to activate other immune cells
–Coordinate actions of other immune cells
Secrete antibodies and provide immune memory
Monocytes: Structure & Function
Structure:
–Monocytes (3% to 8%)
•Usually largest WBC; ovoid, kidney-, or horseshoe-shaped nucleus
Function:
•increased numbers in viral infections and inflammation
–Leave bloodstream and transform into macrophages
- Phagocytize pathogens and debris
- “Present” antigens to activate other immune cells—antigen-presenting cells (APCs)
Platelet: Structure & Function
Structure:
-
•Platelets—small fragments of megakaryocyte cells
–2 to 4 μm diameter; contain “granules”
–Platelet contains a complex internal structure and an open canalicular system
–Amoeboid movement and phagocytosis
•Normal platelet count—130,000 to 400,000 platelets/μL
Function:
–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
Blood Properties
- Viscosity
- Osmolarity
Blood Viscosity
•Viscosity—resistance of a fluid to flow, resulting from the cohesion of its particles
–Whole blood 4.5 to 5.5 times as viscous as water
–Plasma is 2.0 times as viscous as water
•Important in circulatory function
ie: results from the cohesion of its particles. It is the thickness or stickiness of a fluid.
*An RBC or protein deficiency reduces viscosity. and causes the blood to flow too easily. Where as an excess can cause the blood to move in a sluggish way.Either condition puts a strain on the heart and can lead to serious cariovasular problems.
Blood Osmolarity
•Osmolarity of blood—the total molarity of those dissolved particles that cannot pass through the blood vessel wall
–If too high, blood absorbs too much water, increasing the blood pressure
–If too low, too much water stays in tissue, blood pressure drops, and edema occurs
–Optimum osmolarity is achieved by the body’s regulation of sodium ions, proteins, and red blood cells
Hematocrit
Also known as packed cell volume
•centrifuge blood to separate components
–Erythrocytes are heaviest and settle first
•37% to 52% total volume
–White blood cells and platelets
- 1% total volume
- Buffy coat
–Plasma
- The remainder of volume
- 47% to 63%
- Complex mixture of water, proteins, nutrients, electrolytes, nitrogenous wastes, hormones, and gases
Blood Fractionation
Seperation of blood components based on relative densities.
Centrifugation is a method that allows for fractionation.
Erythopoesis
- Erythroposis = erythrocyte production
- 1 million RBCs are produced per second
- Average lifespan of about 120 days
- Development takes 3 to 5 days
Steps:
- Hematopoietic stem cell (HSC) becomes an erythcte colony forming unit (ECFU) - has receptors for erythropoetin (EPI), a hormone secreted by the kidneys
- EPO stimulates the ECFU to transofrm into an erythroblast
- Erythroblasts multiply , build up large cell population.
- Once complete, nucleus shrivels and is discharged from cell- the cell is now called a reticulocyte.
- Reticulocyte leave the bone marrow and enter the citculating blood. Within a day or two, the last of the polyribosomes disintegrate and disappear, and the cell is a matrue erythrocyte.
*About 0.5-1% of circulating RBC are reticulocytes but the percentage may rise under certain circumstances. Blood loss would stimulate erythropoesis.
Leukopoesis
Leukopoesis= production of WBC
Begins with the same HSC as erythropoesis
Some HSC differentiate into distinct types of CFU and then go on to form the following cell lines
- Myeloblasts: ultimately differentiate into 3 types of granulocytes (neutrophils, eosinophils, and basophils)
- Monoblasts- which look identical to myeloblast but lead to monocytes
- Lymphoblasts: which proucte all lymphocytes
•Red bone marrow stores and releases granulocytes and monocytes
CFUS have receptors for colony stimulating factors- mature lymphocytes and macrophages secrete several types of CSFs in response to infections and other immune challenges. Each CSF stimulates a different WBC to develop in response to specific needs. Thus a bacterial infection may trigger the production of neutrophils whereas an allergy stimulates oesinophil prouction, each procress working through its own CSF!
Leukocyte Life Cycle
•Circulating WBCs do not stay in bloodstream
–Granulocytes leave in 8 hours and live 5 days longer
–Monocytes leave in 20 hours, transform into macrophages, and live for several years
–Lymphocytes provide long-term immunity (decades), being continuously recycled from blood to tissue fluid to lymph and back to the blood
Hemoglobin
Structure:
Makes up 33% of RBC
consists of fout protein chains called globins, two are alpha and two are beta
Each chain is conjugatred with a nonprotein moeity called the heme group.
Heme group: bind oxygen to an iron atom.
Function:
Gives RBC its red color
Involved in oxygen transsports
Also aids in carrying away CO2 and buffering blood pH
Heparin
- An anticoagulant released by Basophils
- promotes the mobility of other WBCs in the area
Histamine
- A vasodilator
- Example: released by Basophilsas a way to speed flow of blood to an injured area
Growth Factors
-Platlets secrete growth factors that stimulate mitosis to repair blood vessels
Serotonin
- Vasoconstrictor
- Example: platlets will release during hemostatis during vasccular spasm stage (prompt constriction of a broken vessel- most immediate protection against blood loss)
Thromboxane A2
- An eicosanoid, promotes platelet aggregation, degranulation, and vasoconstriction
- Example: used during platelet plug formation
Erthrocyte Disorders
- Any imbalance between the rates of erythopoesis and RBC destruction may produce an excess or deficiency of red cells.
- RBC Excess: polycythemia
- RBC Deficiency: Anemia
Polycythemia
•an excess of RBCs
–Primary polycythemia (polycythemia vera)
•Cancer of erythropoietic cell line in red bone marrow
–RBC count as high as 11 million RBCs/μL; hematocrit 80%
–Secondary polycythemia
•From dehydration, emphysema, high altitude, or physical conditioning
–RBC count up to 8 million RBCs/μL
•Dangers of polycythemia
–Increased blood volume, pressure, viscosity
Can lead to embolism, stroke, or heart failure
Anemia Types
•Causes of anemia fall into three categories
1.Inadequate erythropoiesis or hemoglobin synthesis
- Kidney failure and insufficient erythropoietin
- Iron-deficiency anemia
- Pernicious anemia—autoimmune attack of stomach tissue leads to inadequate vitamin B_12 absorption
- Hypoplastic anemia—slowing of erythropoiesis
- Aplastic anemia—complete cessation of erythropoiesis
- Hemorrhagic anemias from bleeding
- Hemolytic anemias from RBC destruction
Anemia Consequences
–Tissue hypoxia and necrosis
- Patient is lethargic
- Shortness of breath upon exertion
- Life-threatening necrosis of brain, heart, or kidney
–Blood osmolarity is reduced, producing tissue edema
–Blood viscosity is low
•Heart races and pressure drops
Cardiac failure may ensue
Sickle Cell Disease
- Hereditary defects that occur mostly among people of African descent
- Caused by recessive allele that modifies structure of Hb (makes HbS)
–Differs only on the sixth amino acid of the beta chain
–HbS does not bind oxygen well
–RBCs become rigid, sticky, pointed at ends
–Clump together and block small blood vessels
–Can lead to kidney or heart failure, stroke, joint pain, or paralysis
–Heterozygotes (only one sickle cell allele) are resistant to malaria
Leukocyte Disorders: Types
Normal WBC Count: 5,000-10,000 WBC/ µL
- Lekopenia= a count below this
- Leukocytosis= a count above this
- **Leukemia: cancer of hematopoteic tissues that usually produces an extradoinarly high level of leukoctyes and their precurots.
Leukopenia
•low WBC count: below 5,000 WBCs/μL
–Causes: radiation, poisons, infectious disease
–Effects: elevated risk of infection
Leukocytosis
—high WBC count: above 10,000 WBCs/μL
–Causes: infection, allergy, disease
–Differential WBC count: identifies what percentage of the total WBC count consist of each type of leukocyte
Leukemia
•Leukemia—cancer of hemopoietic tissue usually producing a very high number of circulating leukocytes
–Myeloid leukemia: uncontrolled granulocyte production
–Lymphoid leukemia: uncontrolled lymphocyte or monocyte production
–Acute leukemia: appears suddenly, progresses rapidly, death within months
–Chronic leukemia: undetected for months, survival time 3 years
–Effects: normal cell percentages disrupted; impaired clotting; opportunistic infections
Microscope
Platelet/ Clotting Disorders: Types
•Deficiency of any clotting factor can shut down the coagulation cascade
- Hemophilia: family of hereditary diseases characterized by deficiencies of one factor or another
- Physical exertion causes bleeding and excruciating pain
- Hematomas—masses of clotted blood in the tissues
- Thrombosis—abnormal clotting in unbroken vessel
- Infarction (tissue death) may occur if clot blocks blood supply to an organ (MI or stroke)
Clotting Disorders: Physical Exertion
•Physical exertion causes bleeding and excruciating pain
–Transfusion of plasma or purified clotting factors
–Factor VIII produced by transgenic bacteria
Clotting Disorders: Thrombosis
•Thrombosis—abnormal clotting in unbroken vessel
–Thrombus: clot
•Most likely to occur in leg veins of inactive people
–Pulmonary embolism: clot may break free, travel from veins to lungs
•Embolus—anything that can travel in the blood and block blood vessels
Clotting Disorders: Infarction
•Infarction (tissue death) may occur if clot blocks blood supply to an organ (MI or stroke)
–650,000 Americans die annually of thromboembolism (traveling blood clots)
Clotting Disorders: Hemophilia
- Hemophilia—family of hereditary diseases characterized by deficiencies of one factor or another
- Sex-linked recessive (on X chromosome)
–Hemophilia A missing factor VIII (83% of cases)
–Hemophilia B missing factor IX (15% of cases)
Hemophilia C missing factor XI (autosomal)
Clotting Disorders: Hematomas
masses of clotted blood in the tissues
Platelet Production
•Thrombopoiesis
–Stem cells (that develop receptors for thrombopoietin) become megakaryoblasts
•Megakaryoblasts
–Repeatedly replicate DNA without dividing
–Form gigantic cells called megakaryocytes with a multilobed nucleus
- 100 mm in diameter, remains in bone marrow
- Megakaryocytes—live in bone marrow adjacent to blood sinusoids
–Long tendrils of cytoplasm (proplatelets) protrude into the blood sinusoids: blood flow splits off fragments called platelets
•Platelets circulate freely for 5-6 days
–40% are stored in spleen
Platelet Structure
Structure:
•Platelets—small fragments of megakaryocyte cells
–2 to 4 μm diameter; contain “granules”
–Platelet contains a complex internal structure and an open canalicular system
–Amoeboid movement and phagocytosis
•Normal platelet count—130,000 to 400,000 platelets/μL
Platelet Function
•Platelet functions
–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
Circulatory System
Heart, Blood Vessels, and Blood
Cardiovascular System
Heart & Blood Vessels
Systemic Circuit
- Left side of the heart
- Fully oxygenated blood arrives from the lungs via pulmonary veins
- Blood sent to all organs of the of the body via the aorta
- Thicker Walls to provide more pressure to pump blood throughout the body
Pulmonary Circuit
- Right side of the heart
- Oxygen-poor blood arrives from the inferior & superior vena cava venae cavae
- Blood sent to the lungs via the pulmonary trunk
How can you distinguish between the systemic and pulmonary circuits ?
Pulmonary Circuit
- Pulmonary circulation carries deoxygenated blood from the right ventricle of the heart to the lungs through the pulmonary artery
- Carries oxygenated blood from the lungs to the left atrium of the heart by the pulmonary vein
- Composed of pulmonary artery and pulmonary vein
- Carries blood to the lungs
- Helps to release carbon dioxide from the blood while dissoliving oxygen in the blood
Systemic Circuit
- Systemic Circulation carries oxygenated blood from the left ventricle of the heart to the rest of the body by the aorta
- Carries deoxgenated blood from the body to the right atrium of the heart by the superior and inferior vena cava
- Composed of the inferior and superior vena cava, aorta, and other small blood vessles
- Carries blood throughout the body (including heart)
- Helps to provide nutrients and oxygen to the metabolizing cells in the body
How does the heart supply itself with the oxygen and remove CO2 ?
- Via Coronary Circulation
- Not done through the heart chambers but instead through diffusion of substances through the myocardium
- Myocardium has its own supply of arteries and cappilaries that deliver blood to every muscle cell
- CO2 is removed / drained from the coronary sinus veins
Name these parts
A.Great Cardiac Vein
B.Circumflex branch of Left Cornary Artery (LCA)
C.Coronary Sinus
D.Left marginal branch of LCA
E.Right Coronary Artery (RCA)
F.Right marginal branch of RCA
G.Posterior interventricular branch of RCA
H.Posterior interventricular vein
I.Posterior View
Name these parts
A.RCA
B.Small Cardiac Vein
C.Right marginal branch of RCA
D.LCA
E.Left auricle
F.Circumflex branch of LCA
G.Great Cardiac Vein
H.Anterior interventricular branch of LCA
I.Anterior View
Arterial Supply (anterior)
•Left coronary artery (LCA) branches off the ascending aorta
–Anterior interventricular branch
•Supplies blood to both ventricles and anterior two-thirds of the interventricular septum
–Circumflex branch
- Passes around left side of heart in coronary sulcus
- Gives off left marginal branch and then ends on the posterior side of the heart
- Supplies left atrium and posterior wall of left ventricle