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Flashcards in Blood Study Guide Deck (41)
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1
Q

Define the Cardiovascular System

A

refers to the system only the heart and blood vessels

2
Q

Define Arteries, Capillaries, Veins

A

Arteries- transport blood away from the heart

Capillaries- permeable microscopic vessels between arteries and veins; sites of exchange between blood and body tissues; this is how oxygen and nutrients exit the blood and how carbon dioxide and cellular wastes enter the blood.

Veins- transports blood towards the heart.

3
Q

Describe the general functions of blood

A

Transport- O2, CO2 nutrients, wastes, hormones, and stem cells

Protection- Inflammation, limit spread of infection, destroy microorganisms and cancer cells, neutralize toxins, and initiate clotting

Regulation- Fluid balance, stabilizes pH of ECF, and temperature control

4
Q

Describe the components of blood: plasma and formed elements

A

Adults have 4-6 L of blood.

Blood is a liquid CT consisting of cells and extracellular matrix

Plasma- matrix of blood; clear, light, yellow fluid

Formed elements: Blood cells and fragments; RBCs, WBCs, Platelets

5
Q

Describe the General characteristics of blood

A

Volume in adult body: Females- 4-5 L, Males 5-6 L

Volume/Body Weight: 80-85 mL/kg

Mean Temperature- 38 degrees C (100.4 degrees F)

pH- 7.35- 7.45

Viscosity (relative to water)- Whole Blood: 4.5- 5.5; plasma: 2.0

Osmolarity: 280-296 mOsm/L

Mean salinity (mainly NaCl): 0.9%

6
Q

What percentage of centrifuged blood is occupied by formed elements and plasma?

A

Plasma- 55%

Buffy Coat- < 1% (white blood cells and platelets)

(Formed elements) Red Blood Cells- 45% Hematocrit

7
Q

Define Hematocrit

A

% of RBC in a sample; 45% of the total

8
Q

Describe the composition of plasma

A
92% water
Plasma proteins- 5%= albumins, globulins, fibrinogen
electrolytes
Wastes
Nutrients, vitamins, hormones
Gases- N2, O2, CO2
9
Q

Define Colloid.
What are the Plasma Proteins?
Define colloid osmotic pressure
Define and describe the importance of blood viscosity and osmolarity
Briefly explain why high or low levels of viscosity or osmolarity are a problem.

A

Colloid- a mixture composed of protein within water, where the protein ranges from 1-100 nanometers; appears opaque or milky.

Plasma Proteins include:
Albumins: Smallest most abundant, contribute to viscosity and osmolarity; influence blood pressure, flow, and fluid balance.
Globulins: circulating antibodies, provide immune system functions; alpha, beta, gamma globulins
Fibrinogens: precursor of fibrin threads that help form blood clots

Colloid osmotic pressure- osmotic pressure exerted by plasma proteins; responsible for drawing fluids into the blood and preventing excess fluid loss from blood capillaries into the interstitial fluid.

Viscosity(thickness)- resistance to a fluid to flow, resulting from the cohesion of its particles; slow-moving

Osmolarity- the total molarity of those dissolved particles that cannot pass through the blood vessel wall.

importance of blood viscosity- increased viscosity opposes blood flow and raises blood pressure
Importance of blood osmolarity-
too high (hypertonic)- blood absorbs too much water, therefore, increasing blood pressure,
too low(hypotonic)= too much water stays in tissue, BP drops, resulting in edema.
Optimum osmolarity is achieved by regulation of NA ions, proteins, and RBCs

10
Q

Describe the 4 major plasma proteins and their functions: Albumins, Globulins, Fibrinogens, and Regulatory proteins.

A

Albumins: Smallest most abundant, contribute to viscosity and osmolarity; influence blood pressure, flow, and fluid balance.

Globulins: circulating antibodies, provide immune system functions; contain alpha, beta, gamma globulins

Fibrinogens: precursor of fibrin threads that help form blood clots

Regulatory: includes both enzymes to accelerate chemical reactions in blood and hormones being transported throughout the body to target cells.

11
Q

What are the formed elements?

A

Erythrocytes(RBCs)- 95.1%
Leukocytes (WBCs- neutrophils, basophils, monocytes, lymphocytes)-0.1%
Platelets-4.8%

12
Q

Define hematopoiesis, hemocytoblast, erythropoiesis, myeloid stem cell, proerythroblast, erythroblast, normoblast, reticulocyte. What hormone stimulates RBC production.

A

hematopoiesis- production of blood, especially its formed elements.
hemocytoblast- hematopoietic stem cells; produces myeloid line (erythrocytes, leukocytes) and lymphoid line (lymphocytes).
erythropoiesis- erythrocyte production
myeloid stem cell- what erythropoiesis begins with; ; under the influence of multi CSF forms a progenitor cell
proerythroblast- large, nucleated cell
erythroblast- smaller than proerythroblast; produces hemoglobin in cytosol
normoblast- smaller cell again with more hemoglobin in cytosol, but nucleus ejected.
reticulocyte- lost all organelles except some ribosomes; still can produce hemoglobin through protein synthesis.

the hormone that stimulates RBC production is erythropoietin.

13
Q

Describe Leukopoiesis and thrombopoiesis

A

Leukopoiesis- Production of white blood cells

Thrombopoiesis- production of platelets

14
Q

Describe an erythrocyte

A

Diameter-7.5 micrometers
2.0 micrometers thick at rim

Most of the organelles lost

Lacks mitochondria- anaerobic formation to produce ATP
Lacks nucleus and DNA- no protein synthesis or mitosis

15
Q

Describe the 2 principle functions of erythrocytes

A
  1. Carry O2 from lungs to cells tissue

2. Pick up CO2 from tissues and bring to lungs

16
Q

Define the hemoglobin. Briefly describe its color, abundance in RBC, and its 3 functions

A

hemoglobin- red-pigmented protein that transports O2 and CO2.

33% in RBC. Hb is bright red when oxygenated and darker red when deoxygenated.

Each Hb molecule consists of:

  1. 4 heme groups that bind O2 to its Fe and can transport 4 O2 molecules.
  2. Globin is the protein portion of hemoglobin and binds about 5% of CO2 in blood.
  3. Globin can also bind Hydrogen ions (H+) which helps buffer the blood and maintain pH.
  4. Acts as a buffer
17
Q

Discuss two ways in which a RBC is an example of complexity of structure and function: lack of mitochondria and plasma proteins.

A

lack of mitochondria- forces RBCs to make ATP exclusively by anaerobic respiration or fermentation so they don’t consume the O2 they are transporting.

Plasma proteins- give membrane durability and resilience; stretch and bend as squeezed through small capillaries.

18
Q

Describe hemoglobin structures and their gas carrying ability: globins and heme

A

Each Hb molecule consists of:

  1. 4 heme groups that bind O2 to its Fe and can transport 4 O2 molecules.
  2. Globin is the protein portion of hemoglobin and binds about 5% of CO2 in blood.
  3. Globin can also bind Hydrogen ions (H+) which helps buffer the blood and maintain pH.
  4. Acts as a buffer
19
Q

Why is iron essential in RBC? Describe the stomach’s role with dietary iron.

A

Iron= key nutritional requirement; it is lost daily through urine, feces, and bleeding.
Men 0.9 mg/ day and women 1.7 mg/day
Low absorption rate of iron requires consumption of 5 to 20 mg/ day.

Dietary iron: ferric (Fe3+) and ferrous (Fe2+)
Stomach acid converts Ferric into absorbable ferrous.

20
Q

Briefly describe the roles of the proteins transferrin and ferritin in iron metabolism.

A

ferratin- binds Fe2+ and transports it to small intestine.

Transferrin- transports iron to bone marrow, liver, and other tissues.

21
Q

Define biliverdin and bilirubin. Define urobilinogen, stercoblin, and urobilin.

A

biliverdin- green pigment heme is converted to
bilirubin- yellow pigment biliverdin is converted to

urobilinogen- brown feces
stercoblin- brown pigment expelled from body as a component of feces

urobilin- yellow pigment excreted by kidneys.

22
Q

Explain what determines a person’s blood type. Define antigen (agglutinogen) and antibodies (agglutinins), and agglutination.

A

Surface antigens (agglutinogens), ABO blood group and Rh protein, determine the blood type.

antigen (agglutinogen)- complex glycolipid molecules on surface of RBC cell membrane that activate an immune response; genetically unique to individual; cell identity markers; determine blood type.

antibodies (agglutinins)- circulates in plasma; can form an antigen-antibody complex; antibodies in the plasma that bring about transfusion mismatch.

agglutination- antibody molecule binding to antigens; causes clumping of RBCs.

23
Q

Explain how a person’s blood types relate to transfusion compatibility. Define a transfusion reaction.

A

Blood types and transfusion compatibility are a matter of interactions between plasma proteins and erythrocytes.

transfusion reaction- if a person receives mismatched blood plasma bind to their respective surface antigens within the erythrocyte plasma membrane; erythrocytes clump and may block small blood vessels.

24
Q

Explain what determines a person’s Rh blood group.

A

The patient is considered Rh+ if having D antigen (agglutinogens) on RBCs.

25
Q

Describe the cause, prevention, and treatment of Hemolytic disease of the newborn.

A

Hemolytic disease of a newborn can occur if Rh- mother has formed antibodies and is pregnant with 2nd Rh+ child.

prevention: RhoGAM given to pregnant Rh- women; binds fetal agglutinogens in her blood so she will not form anti-D antibodies.

26
Q

Explain the function of leukocytes (WBC). Define diapedesis and chemotaxis.

A

Leukocytes- protect against infectious microorganisms and other pathogens.

Diapedesis- leukocytes squeezing between endothelial cells of blood vessel walls.

chemotaxis- leukocytes are attracted to site of infection by the presence of molecules released and damaged by cells, dead cells, or invading pathogens.

27
Q

What distinguishes granulocytes and from agranulocytes?

A

granulocytes: specific granules in their cytosol; neutrophils, eosinophils, basophils
agranulocytes: small specific granules in the cytosol that are not clearly visible under a microscope; monocytes, lymphocytes.

28
Q

List and briefly describe the appearance, size, number, and function of 3 types of granulocytes.

A

Neutrophils- 9-12 micrometers, 50-70%, polymorphonuclear leukocytes, barely visible granules in cytoplasm; 3-5 lobed nucleus; aggressively antibacterial; phagocytic; neutrophilia- rise in # of neutrophils in response to bacterial infection.

Eosinophils- 10-14 micrometers, 1-4%; large rosy- orange granules, bilobed nucleus, phagocytize antigen-antibody complexes, produce peroxidase against parasitic worms, play a role in allergic response.

Basophils- 8-10 micrometers, less than 1%, large, abundant, blue-violet granules, obscure a large bilobed, s-shaped nucleus; increased #s in chickenpox, sinusitis, diabetes; secrete histamine, secrete heparin.

29
Q

Briefly describe the appearance, size, number, and function of the two types of agranulocytes.

A

Monocytes- 12-15 micrometers, 2-8%, kidney or horseshoe-shaped nucleus, leave bloodstream and transform into macrophages, phagocytize pathogens and debris, “present” antigens to activate other immune systems.

Lymphocytes- 5-7 micrometers, 20-40%, ovoid/round, large, uniform dark violet nucleus
Immunological cells- t-cells coordinate with immune cell activity, b-cells become plasma cells and produce antibodies, NK cells attack abnormal (cancer) cells and infected tissue.

30
Q

Define Differential WBC count. Define leukopenia and leukocytosis. List the causes and effects of each

A

differential WBC count- measures the amt of each type of leukocyte in your blood, and determines whether any of the circulating leukocytes are immature.

leukopenia- reduced # of leukocytes; causes the person to have to risk of a person developing an infection or decrease the ability to fight infection.

Leukocytosis- slightly elevated leukocyte count and may be caused by a variety of factors such as recent infection or stress.

31
Q

Describe platelet structure and give the typical platelet count.

A

platelets (thrombocytes) irregular-shaped, membrane-enclosed cellular fragments that are about 2 micrometers in diameter; no nucleus. In adults, they range from 150,00 to 400,00 per cubic millimeter of blood.

32
Q

Briefly describe the site and process of platelet production (thrombopoiesis) and the hormone that stimulates it.

A

thrombopoiesis- produced in red bone marrow by megakaryocytes.

the hormone that stimulates thrombopoiesis is thrombopoietin.

33
Q

define hemostasis

A

hemostasis- stoppage of bleeding (happens when cut).

34
Q

Briefly describe the relative quickness and effectiveness of the 3 homeostatic mechanisms of hemostasis: vascular spasm, platelet plug formation, and coagulation

A

Vascular spasm- prompt constriction of a broken vessel; most immediate protection against blood loss.
Pain receptors- short duration (minutes)
Smooth muscle injury- longer duration; provides time for other two clotting pathways.

Platelet plug formation- intact vessel have a smooth endothelium coated with prostacyclin- a platelet repellant.
Broken vessel exposes collagen; makes platelets sticky.
Platelets degranulate releasing serotonin, ADP, snd thromboxane A2

Coagulation (clotting)- last and most effective defense against bleeding
conversion of plasma protein fibrinogen into insoluble fibrin threads to form framework of clot.

35
Q

What is the source and significance of prostacyclin, thromboxane A and ADP?

A

Prostacyclin- what smooth endothelium is coated with; platelet repellant

Thromboxane A- an eicosanoid promoting platelet aggregation, degranulation, and vasoconstriction.

ADP- attracts and degranulates more platelets

36
Q

Describe the process of platelet plug formation.

A

Intact vessels have a smooth endothelium coated with prostacyclin- a platelet repellant.

Broken vessel exposes collagen; makes platelets sticky.

Psuedopods contract- draw together a platelet plug. Platelets degranulate releasing a variety of substances: serotonin (vasoconstrictor), ADP (attracts and degranulates more platelets)
Thromboxane A2 (eicosanoid)- promotes platelet aggregation, degranulation, and vasoconstriction.

Positive feedback cycle is active until break in small vessel is sealed.

37
Q

Describe the process of platelet plug formation: extrinsic and intrinsic mechanisms.

A

extrinsic pathway (cuts)- factors released by damaged tissues begin to cascade.

intrinsic pathway (unwanted clots)- factors found in blood begin to cascade (platelet degranulation).

38
Q

compare what factors initiate coagulation in the intrinsic and extrinsic mechanisms. What common factor is the end result for both mechanisms?

A

the common factor is Factor X- leads to production of prothrombin activator

39
Q

Follow the steps of coagulations from factor X to fibrin including coagulants or clotting factors.

A
  1. Active Fiber X combines with factors II and V, Ca2+, and platelet factor 3 to form prothrombin activator.
  2. Prothrombin activator activates prothrombin to thrombin.
  3. Thrombin converts soluble fibrinogen into insoluble fibrin.
  4. In the presence of Ca2+, factor XIII is activated, Factor XIII cross-links and stabilizes the fibrin monomers into a fibrin polymer that serves as the frame of the clot.
40
Q

What is the sympathetic response to blood loss?

A

Survival response is initiated. As blood volume decreases, blood pressure decreases. Increased vasoconstriction, increased heart rate, and increased force of contraction in an attempt to maintain blood pressure.

41
Q

Explain what happens to blood clots when no longer needed: clot retraction, plasmin, vessel repair, and fibrinolysis.

A

clot retraction- occurs as clot is forming when actinomyosin, a contractile protein within platelets, contracts and squeezes the serum out of the developing clot. Makes clot smaller.

Plasmin- degrades fibrin strands through fibrinolysis.

fibrinolysis- dissolution of clot