chapter 17-blood
What is a hematocrit? A hematocrit is the percentage of leukocytes and platelets in a whole blood sample. A hematocrit is the percentage of plasma in a whole blood sample. A hematocrit is the percentage of erythrocytes in a whole blood sample. A hematocrit is the percentage of all formed elements in a whole blood sample.
A hematocrit is the percentage of erythrocytes in a whole blood sample.
Mr. Watkins's blood type was determined to be A positive. Which of the following types of blood can he receive? Only A positive and O negative. A positive but not A negative. A positive, A negative, O positive, and O negative. A positive, O positive, and AB positive.
A positive, A negative, O positive, and O negative.
Mr. R has beta-thalassemia minor; he is heterozygous for the beta-thalassemia gene, so he only makes half as many beta chains as normal. The red blood cells containing abnormal hemoglobin are destroyed more rapidly, so Mr. R suffers from mild anemia (low hematocrit). What are the beta chains, and why are they important in the hemoglobin molecule? Beta chains are the part of the erythrocyte that holds the hemoglobin in position so it can properly receive oxygen. Beta chains are the part of the hemoglobin that carries oxygen. All of the protein in hemoglobin is beta chains; therefore, hemoglobin could not exist without them. Beta chains are two of the four protein chains that hold heme groups in position and modulate their oxygen-binding properties.
Beta chains are two of the four protein chains that hold heme groups in position and modulate their oxygen-binding properties.
Which image shows the type of leukocyte responsible for antibody production? Five basic types of leukocytes. E C D B
D (The leukocyte in image D may directly target pathogens or produce antibodies.)
During which event of hemostasis do clotting factors (procoagulants) assist with the transformation of blood from a liquid to a gel? A B C D
D The gelling of blood due to formation of insoluble fibrin occurs during the coagulation stage.
Which of the following is true of the structure of an erythrocyte? Erythrocytes are cell fragments. Erythrocytes are larger than other cells in the blood. Erythrocytes are nucleated cells. Erythrocytes can bend and twist to fit through vessels.
Erythrocytes can bend and twist to fit through vessels.
If Maggie needed a blood transfusion immediately upon her arrival to the ED, before her blood type could be established, what type could be safely transfused? AB- No blood type can be safely transfused into every person. O+ O-
O-
Why was Mr. Watkins given PRBCs in addition to normal saline solution? What problem does the infusion of PRBCs address that the saline solution could not? PRBCs contain hemoglobin, so they are able to carry oxygen to the tissues. PRBCs enhance clotting, sealing off the injured vessels. PRBCs help restore blood ion composition to normal. PRBCs increase blood osmotic pressure, making the infused fluid stay in the vessels rather than move into the cells.
PRBCs contain hemoglobin, so they are able to carry oxygen to the tissues.
Which of the following sets of measurements from Harold's CBC does his doctor use to evaluate the health of his immune system? hematocrit, hemoglobin, RBC count neutrophil, basophil, platelet count WBC, hematocrit, platelet count WBC, neutrophil, basophil count
WBC, neutrophil, basophil count
What part of the hemoglobin molecule is eventually metabolized to stercobilin in the feces? transferrin a portion of the heme group iron globin
a portion of the heme group
The infusion of mismatched blood causes a "transfusion reaction" in which the infused RBCs go through __________. excessive coagulation erythropoiesis agglutination and hemolysis inflammation-induced anticoagulation
agglutination and hemolysis
Which part of the hemoglobin molecule binds carbon dioxide for transport? amino acids of the globin spectrin heme group iron
amino acids of the globin
During erythroblastosis fetalis, a Rh− mother's anti-Rh antibodies that have crossed the placenta will cause agglutination of the fetus's Rh+ RBCs. However, the reverse problem never happens when a Rh+ mother is pregnant with a Rh− fetus; that is, antibodies produced by the fetus cannot cause agglutination of the mother's Rh+ RBCs. This is true because ______. agglutinins are physically too large to pass across the placenta fetal antibodies are immature and non-functional antibodies that can cause this agglutination are not produced by a fetus the placenta is a barrier that prevents the passage of all antigens
antibodies that can cause this agglutination are not produced by a fetus (The (+) in Rh+ indicates that the red blood cells of the fetus have this agglutinin (antigen) on their surface. Therefore, they don't produce antibodies to that surface protein. If the fetus made these antibodies, agglutination would occur in their own (fetal) blood.)
Which of these is most likely in the event of excessive consumption of erythrocytes by macrophages? blood levels of oxygen would rise blood levels of bilirubin would rise erythropoietin levels would fall the hematocrit would rise
blood levels of bilirubin would rise
Erythropoietin (EPO) stimulates the developmental process shown here. What part of the body does erythropoietin (EPO) target to increase erythropoiesis? bone marrow liver kidneys lungs
bone marrow
Athletes can use industry-produced EPO as a performance-enhancing drug to increase the effects of their naturally-produced EPO. These athletes will experience ______. decreased production of EPO by their kidneys decreased erythropoiesis decreased reticulocyte counts None of the listed responses is correct.
decreased production of EPO by their kidneys
Doctors have determined that Harold is anemic. Which of the following pieces of evidence directly supports this diagnosis? fatigue, dizziness, and low hematocrit tachycardia, headaches, and elevated neutrophil count dizziness, difficulty breathing, and elevated basophil count nausea, elevated WBC, and low RBC
fatigue, dizziness, and low hematocrit (The low hematocrit suggests an abnormally low number of circulating red blood cells. The fatigue and dizziness are the result of a diminished oxygen-carrying capacity. These are all signs of anemia.)
How many oxygen molecules can be transported by one hemoglobin molecule? two four eight
four
Which of the following sets of measurements from Harold's CBC does his doctor use to evaluate his body's ability to oxygenate his tissues? WBC, neutrophil, basophil count WBC, hematocrit, platelet count neutrophil, basophil, platelet count hematocrit, hemoglobin, RBC
hematocrit, hemoglobin, RBC
What part of the pathway to produce platelets is shared with other formed elements? reticulocyte hematopoietic stem cell (hemocytoblast) megakaryoblast lymphoid stem cell
hematopoietic stem cell (hemocytoblast)
What is the name of the protein found in erythrocytes that transports respiratory gases and provides the red color? fibrinogen albumin hemoglobin antibody
hemoglobin
A test tube of Maggie's blood goes unused in the lab, and the stagnant blood coagulates. This is due to which pathway of blood clotting? extrinsic pathway intrinsic pathway
intrinsic pathway
The three types of formed elements of blood are ________. plasma proteins, erythrocytes, and leukocytes leukocytes, plasma proteins, and platelets leukocytes, platelets, and erythrocytes erythrocytes, leukocytes, and plasma
leukocytes, platelets, and erythrocytes
From which cell do the granulocytes descend? myeloblast monoblast promonocyte lymphoid stem cell
myeloblast
In a cancer patient undergoing chemotherapy, the decision to utilize a CSF capable of specifically stimulating the production of only the granular leukocytes would require that the CSF acts exclusively on ______. lymphoid stem cells myeloid stem cells myeloblasts lymphoblasts
myeloblasts
What erythrocyte production disorder results from an autoimmune disease associated with insufficient vitamin B12 absorption (step 6)? pernicious anemia aplastic anemia hemorrhagic anemia renal anemia
pernicious anemia (A glycoprotein called intrinsic factor, produced by the stomach, is required to absorb adequate vitamin B12. Pernicious anemia results when the stomach does not produce adequate intrinsic factor, often because the cells that produce it are attacked by the body's immune system.)
During which phase in erythrocyte development does the color of hemoglobin overcome the color of the stained ribosomes? phase 1 phase 2 phase 3
phase 2
Which of these makes up the greatest portion of whole blood by volume? erythrocytes leukocytes plasma platelets
plasma
Which of these develops from lymphoid stem cells? granulocytes plasma cells erythrocytes monocytes
plasma cells (Both T and B lymphocytes arise from lymphoid stem cells. Plasma cells are cloned from activated B lymphocytes.)
The two most abundant components of whole blood, in order of most abundant and second-most abundant, are _________. plasma, erythrocytes plasma, leukocytes leukocytes, erythrocytes erythrocytes, platelets
plasma, erythrocytes
What enzyme removes unneeded clots after healing has occurred? fibrin plasmin thrombin plasminogen
plasmin
Which formed element can be described as cytoplasmic fragments? platelets monocytes erythrocytes megakaryocytes
platelets
What is the complete hemoglobin molecule composed of? polypeptide chains (globins), heme groups, and iron ions heme groups and iron ions heme groups and polypeptide chains (globins) iron ions and polypeptide chains (globins)
polypeptide chains (globins), heme groups, and iron ions
What triggers erythropoietin (EPO) release that leads to the production of new red blood cells? a high hematocrit excess oxygen in the bloodstream too many platelets reduced availability of oxygen
reduced availability of oxygen
What is a young, anucleate erythrocyte called? polychromatic erythroblast proerythroblast hemopoietic stem cell (hemocytoblast) reticulocyte
reticulocyte
Assuming all of the following fluid-replacement options are equal (with respect to risks, availability, and cost), which would be the most optimal for Maggie when you consider her significant blood loss? packed cells (concentrated RBCs with most plasma removed) normal saline solution (no RBCs, just water and NaCl that is the approximate consistency of plasma minus the proteins) whole blood (blood that is the normal consistency of blood in the body) free water (no added solutes)
whole blood (blood that is the normal consistency of blood in the body) (the optimal replacement is whole blood because the patient has lost red blood cells and plasma in equivalent amounts. That is, she needs both RBCs and plasma replacement.)
Maggie's cuts are successfully treated, and the physician elects not to transfuse any blood products. A week later she visits her primary physician to have her sutures removed, and her hematocrit has improved. Calculate this HCT: the total volume is 5 ml, and the plasma volume is 3.4 ml. Is it normal? 32%. This value is low for a woman. 46%. This value is normal for a woman. 32%. This value is normal for a woman. 74%. This value is high for a woman.
32%. This value is low for a woman. (In this question, students must calculate packed cell volume by subtracting the plasma volume value from the total blood volume (5 - 3.4 = 1.6 ml); then, 1.6/5 ml × 100 = 32%. The normal hematocrit in healthy females is approximately 42% ± 5%, and in a healthy male, it is 47% ± 5%.)
In the laboratory, the technician determines Maggie's blood type. Maggie's blood agglutinates in anti-A antibodies, but has no reaction in anti-B or anti-D antibodies. What is Maggie's blood type? A+ A- B+ B-
A-
What blood type(s) can Maggie safely receive? B+ and O+ O- only A- and O- A- only
A- and O-
Which of the following best explains how platelets enter the blood? They are formed in the spleen and are released directly into the blood. They are formed in and released by the thymus. They form in the blood itself as it passes through the lungs. They are passed through the wall of a bone marrow capillary.
They are passed through the wall of a bone marrow capillary.
Harold's doctor noted that he was experiencing a mild tachycardia. Which of the following best explains why Harold would be experiencing tachycardia in this case? The elevated heart rate is causing his gastritis because inflammatory cells are being delivered to his stomach at a faster-than-normal rate. Harold is showing signs and symptoms of having trouble oxygenating his tissues. The elevated heart rate helps to compensate for this problem. Harold has lost a significant amount of blood volume. The elevated heart rate helps to compensate for this problem. Harold is showing signs and symptoms of having a clotting disorder. The elevated heart rate helps to compensate for this problem.
Harold is showing signs and symptoms of having trouble oxygenating his tissues. The elevated heart rate helps to compensate for this problem.
Which of the following is FALSE regarding the role of platelets in hemostatic reactions? Platelets do not stick to intact endothelial cells. Platelets release chemicals that attract and bind other platelets. Platelets adhere to exposed collagen fibers. Platelets release the only chemical factors that can initiate coagulation.
Platelets release the only chemical factors that can initiate coagulation.
Based on Harold's history of gastritis, his doctor ordered a blood test in order to measure his levels of vitamin B12. Which of the following explains why his doctor would take this action? High levels of circulating vitamin B12 can cause gastritis. The stomach makes vitamin B12 and damage could lead to less being made. The stomach makes intrinsic factor, which is required for vitamin B12 absorption in the small intestine. Gastritis is an inflammatory condition, and inflammatory cells destroy vitamin B12.
The stomach makes intrinsic factor, which is required for vitamin B12 absorption in the small intestine
Which of these is true of the materials making up the buffy coat in centrifuged blood? They are denser then plasma and erythrocytes. They are denser than erythrocytes but less dense than plasma. They are intermediate in density between erythrocytes and plasma. They are less dense than both erythrocytes and plasma.
They are intermediate in density between erythrocytes and plasma.
