CH 18 Flashcards
What is included in the cardiovascular system (not circulatory)?
Blood vessels and the heart
What are the components of blood?
Platelets, WBCs, RBCs, and Plasma
What are the functions of plasma proteins?
Clotting, immune defense, and transport of iron, copper, lipids, and hydrophobic hormones
Which property of blood is defined as the total molarity of dissolved particles that cannot pass through the blood vessel wall?
Osmolarity
What term refers to the production of blood, especially the formed elements?
Hematopoiesis
Which blood cells are critical to survival because of their ability to transport oxygen?
Erythrocytes
Which blood cells are biconcave and lack a nucleus and other organelles?
Erythrocytes
Functions of Albumin
Solute transport, pH buffering, regulation of blood viscosity and osmolarity
Globulins function
Immunity
Fibrinogen function
Clotting
Structure of adult hemoglobin
2 alpha chains and 2 beta chains
What could decreased blood osmolarity lead to?
Low blood pressure and Edema (too much water in the tissues , swollen tissues)
T or F: Erythrocytes circulate for about 120 days before they die
True
What is the most abundant formed element of the blood?
Erythrocytes
What is the role of Erythropoietin (EPO)?
Stimulates RBC production
At which stage of erythrocyte development are the RBCs released into the blood?
Once they are Reticulocytes, they are released from the bone marrow into the blood
How many heme groups are there in each hemoglobin molecule?
- Heme groups bind oxygen to iron. 1 hemoglobin molecule can carry 4 molecules of oxygen
What nutrient is critical for hemoglobin synthesis?
Iron
How long does it take to produce Erythrocytes?
Usually 3 to 5 days
What is a possible side effect of excessive antacid use?
Decreased absorption of iron by the intestine
Old blood cells usually die as they pass through what organ?
The spleen
What organ secretes Erythropoietin (EPO)?
The kidneys
The rupture of red blood cells is called what?
Hemolysis
How do reticulocytes differ from mature red blood cells?
Reticulocytes have polyribosomes and are far less numerous than RBCs. Only 0.5-1.5% of circulating blood cells are reticulocytes
Inadequate Erythropoietin or hemoglobin synthesis, hemorrhage, and increased RBC destruction are all common causes of what erythrocyte disorder?
Anemia
Steps of Iron Metabolism after absorption from Small intestine into Blood stream
1) Absorbed Fe2+ (ferrous ion) binds to transferrin in blood plasma
2) Some transferrin releases Fe2+ for storage in the liver
3) Fe2+ binds apoferritin to be stored as ferritin in the liver
4) Remaining transferrin goes to other organs where Fe2+ is used
Antigens on the surface of Erythrocyte membranes determine what?
Blood type
Iron needs to be in the Fe2+ form to be absorbed. What converts Fe3+ to Fe2+?
Stomach Acid
Why are only old RBCs destroyed in the spleen?
Old cells rupture in the narrow channels of the spleen because they are no longer flexible and resilient
A person who has A+ blood has what antigens expressed on the surface of their RBCs?
Antigen A and Antigen D
What is hemolysis?
The destruction of RBCs
What causes hemolytic disease (erythroblastosis) of the newborn (HDN)?
Maternal anti-D destroys fetal erythrocytes
A person’s specific blood type is based on what?
Antigens expressed on the RBC plasma membrane
Which WBCs are classified by agranulocytes?
Monocytes and lymphocytes
Which erythrocyte cell-surface antigens determine a person’s ABO blood group?
Antigens A and B (O is the absence of antigen A or B)
The most numerous WBCs are usually what?
Neutrophils
What term refers to the development of WBCs?
Leukopoiesis
What types of leukocytes are classified as granulocytes?
Neutrophil, eosinophil, and basophils
A giant precursor cell with a multilobed nucleus and fragments to form platelets
Megakaryocyte
What is hemostasis?
A physiological process that controls/prevents excessive bleeding
WBC differential % in a healthy person
Neutrophils 60-70%
Lymphocytes 25-33%
Monocytes 3-8%
Eosinophils 2-4%
Basophils < 0.5%
What are the 3 hemostatic mechanisms?
Vascular spasm, platelet plug formation, blood clotting
What is leukopoiesis?
Production of WBCs
What is vascular spasm?
A short-lived mechanism in which the damaged vessel narrows to minimize blood loss
What is the purpose of a differential WBC count?
To determine the number and ratio of each type of leukocyte in a sample
What may activate platelets?
Exposed collagen
What are megakaryocytes?
Giant bone marrow cells that break off to produce platelets
As platelets aggregate during the second step of hemostasis, which events occur?
Platelets degranulate resulting in the release of thromboxane A, ADP and serotonin
What is the first response to a blood vessel injury?
Vascular spasm
What is the main goal of coagulation?
Conversion of fibrinogen into fibrin
When collagen in the wall of a blood vessel is exposed as a result of injury, ______ adhere and develop long, spiny pseudopods which draw the vessel walls back together
Platelets
The release of clotting factors by damaged blood vessels and peri vascular tissues initiates what pathway of coagulation?
Extrinsic pathway
The reproduction of fibroblasts and smooth muscle cells during injury repair is triggered by what?
Platelet-derived growth factor (PDGF)
Steps of Platelet Plug formation
1) Contact with collagen of a broken vessel or another rough surface
2)Platelets grow long spiny pseudopods
3)Pseudopods contract and draw the vessel walls together
4)Mass of platelets forms a platelet plug
What term refers to the interaction of protein factors to form a clot?
Coagulation
Platelet repulsion, dilution, and substances like heparin or anti thrombin help do what?
Prevent inappropriate clotting
The clotting cascade that originates within the blood itself is called what?
Intrinsic pathway
What term refers to a blood clot that breaks loose and travels throughout the bloodstream?
An Embolus
When they are in the tissues, masses of clotted blood are called?
Hematomas
RBC Count
The total number of RBCs in the blood
Hemoglobin Concentration
The measure of the concentration of hemoglobin in a given volume of packed red blood cells
Hematocrit
The percentage of whole blood volume composed of RBCs
Beginning of Extrinsic Pathway
Damaged vessel releases thromboplastin (Factor III)
Beginning of Intrinsic Pathway
Aggregated platelets release Hageman factor (factor XII)
List the leukocytes from most abundant to least in healthy individuals
Neutrophils, lymphocytes, monocytes, eosinophils, and basophils
Leukopenia
A total WBC count below 5,000 cells/uL
Leukemia
Cancer that produces a high number of circulating leukocytes and their precursors
Myeloid Leukemia
Marked by uncontrolled granulocyte production (myeloid tissue refers to bone marrow)
Lymphoid Leukemia
Involves uncontrolled lymphocyte or monocyte production
Leukocytosis
A total WBC count above 10,000 cells/uL
Acute Leukemia
Appears suddenly, progresses rapidly, and causes death within a few months
Chronic Leukemia
Develops more slowly and may go undetected for many months
Hypoxemia
Inadequate oxygen transport
Hypoxemia Negative Feedback Loop
1) Inadequate oxygen transport is detected by the kidneys and liver
2) When detected, erythropoietin (EPO) is produced and secreted
3) EPO stimulates the red bone marrow to produce RBCs
4) Oxygen transport throughout the body increases
Circulatory System refers to?
Heart, blood vessels, and blood
The body’s regular pH
7.4
What do Hemo- , Leuko- , and Erythro- mean?
Blood, white, and red
Why does BLOOD transport oxygen?
Because blood interacts with all the tissues all over the body
Why does blood transport OXYGEN?
Because oxygen provides a lot more energy for aerobic respiration than the amount of energy that can be produced from anaerobic respiration
What is Urea?
The most abundant nitrogenous waste
What are the plasma proteins?
Albumins, Globulins, and Fibrinogens
What does plasma lack that other connective tissues all have?
Plasma lacks fibers
What produces most of the plasma proteins?
The liver
What is the difference between blood plasma and serum?
In blood serum, the clotting factors have been filtered out
Hypoxia vs Hypoxemia
Hypoxia is not enough oxygen in the tissues and Hypoxemia is not enough oxygen in the blood
Why do tissues need oxygen to survive?
Tissues need oxygen to survive to produce ATP and synthesize proteins, to divide and multiply, and to conduct active transport of ions across cell membranes
What fraction of a L is a deciliter (dL) and what fraction of a L is a microliter (uL)?
1/10 of a liter and 1/1,000,000 of a liter
How many total cells are in your body rn?
About 50 trillion cells
What does Hematopoiesis refer to?
The production of ALL blood cells especially the formed elements
What produces blood cells in a fetus?
The liver, spleen, and thymus
What is the primary job of a stem cell?
Mitosis
Most abundant WBC
Neutrophil
Least abundant WBC
Basophil
Why do people that live at higher altitudes have higher RBC counts?
At higher altitudes there is less oxygen per breath. To compensate for that, RBC count increased to be able to grab more oxygen per breath and hold on to it as it comes into the lungs
What produces hemoglobin?
Erythroblasts
What foods contain dietary iron? Folic Acid? Vitamin C?
Meat and dark leafy greens
Dark leafy greens
Citrus like oranges
Where is excess iron stored?
In the liver
What helps store necessary dietary nutrients?
Intrinsic factor in the small intestine
Where is the spleen?
In left abdominal cavity
What is jaundice an indication of?
Liver damage/failure
Why do we only have 2 genes for every trait?
Because we get a gene from each parent, one from the mother and one form the father
What type of agglutinins (antibodies) do type O people produce?
Anti-A and Anti-B
What type of agglutinins do type AB people produce?
They produce neither agglutinin
Hemostasis
The control/cessation of bleeding
Hemorrhage
Excessive, uncontrolled bleeding (potentially fatal)
Why doesn’t your blood clot while its flowing?
Because there are anti-coagulant factors in the blood and the blood is diluted enough that clotting factors do not activate
What fiber is necessary for a blood clot?
Fibrin
What is a scab?
A scab is a dried blood clot
What is the stimulus for the positive feedback loop in platelet plug formation?
The exposed collagen that attracts platelets in the beginning
How would liver disease affect blood clotting?
Both prothrombin and fibrinogen are produced in the liver and are the precursors for the formation of Thrombin and thrombin is needed for formation of fibrin. Without these enzymes readily circulating in the blood, blood clotting will not happen efficiently enough
Action of Thrombin
Converts fibrinogen to fibrin
What Clotting pathway is more efficient?
Intrinsic pathway because while it has more steps, at each step more and more clotting factor is produced
What is Plasmin?
Plasmin is the enzyme that dissolves a clot
Prostacylin
Makes the endothelium a slippery surface to prevent erythrocytes from sticking to it
Most common form of Hemophilia
Hemophilia A , makes up for 83% of cases, is X-linked recessive , and is caused by missing factor VIII
Pulmonary embolism
A blood clot that moves to the lungs
Infarction
Death of tissue due to lack of oxygen
Common anticoagulants
Warfarin (prevents formation of fibrin) , Aspirin (suppresses thromboxane A2)
How does Hypoxemia lead to polycythemia?
Hypoxemia leads to an increase in erythropoiesis which can temporarily result in higher than normal levels of RBCs until the levels balance out
Negative affect of Sickle Cell shaped RBCs
Spiky cells can damage internal wall of capillary and cause the formation of clots
If both parents are carriers of Sickle Cell anemia, what are the chances offspring will have it?
25% chance
What is the most abundant plasma protein?
Albumin
