CSS - PMS - CCE - PCS - General Science
Blood System
The extracellular matrix of blood is:
A. Plasma
B. Hemoglobin
C. Bone marrow
D. Fibrin only
Correct Answer: A
Plasma is the fluid extracellular matrix in which blood cells and platelets are suspended.
CSS - PMS - CCE - PCS - General Science
Blood System
Blood is classified as a type of:
A. Connective tissue
B. Epithelial tissue
C. Muscle tissue
D. Nervous tissue
Correct Answer: A
Blood is considered a specialized fluid connective tissue because cells are suspended in an extracellular matrix, plasma.
CSS - PMS - CCE - PCS - General Science
Blood System
The principal hormone regulating platelet production is:
A. Thrombopoietin
B. Erythropoietin
C. Insulin
D. Renin
Correct Answer: A
Thrombopoietin, produced mainly by the liver, is the key regulator of megakaryocyte and platelet production.
CSS - PMS - CCE - PCS - General Science
Blood System
The production of platelets is termed:
A. Thrombopoiesis
B. Erythropoiesis
C. Leukolysis
D. Fibrinolysis
Correct Answer: A
Thrombopoiesis is platelet production from megakaryocytic precursors.
CSS - PMS - CCE - PCS - General Science
Blood System
Eosinophilia is often associated with:
A. Parasitic infection or allergic disease
B. Iron transport only
C. ABO incompatibility only
D. Dehydration only
Correct Answer: A
Eosinophil counts commonly rise in parasitic infections and many allergic conditions.
CSS - PMS - CCE - PCS - General Science
Blood System
Differential leukocyte count refers to the relative numbers of:
A. Different types of white blood cells
B. Different ABO groups
C. Different plasma proteins
D. Different clotting factors
Correct Answer: A
A differential count reports proportions or absolute counts of neutrophils, lymphocytes, monocytes, eosinophils and basophils.
CSS - PMS - CCE - PCS - General Science
Blood System
A complete blood count (CBC) commonly includes measurement of:
A. RBCs, WBCs, hemoglobin and platelets
B. Only blood group
C. Only plasma glucose
D. Only clotting time
Correct Answer: A
A CBC reports major cellular components and red-cell indices, including RBC and WBC counts, hemoglobin and platelets.
CSS - PMS - CCE - PCS - General Science
Blood System
Citrate prevents blood clotting primarily by binding:
A. Calcium
B. Iron
C. Sodium
D. Albumin
Correct Answer: A
Citrate chelates calcium ions and is widely used for coagulation testing and blood storage.
CSS - PMS - CCE - PCS - General Science
Blood System
EDTA is commonly used in hematology samples because it:
A. Chelates calcium and prevents clotting
B. Adds fibrinogen
C. Destroys red cell membranes intentionally
D. Increases oxygen saturation
Correct Answer: A
EDTA binds calcium, an essential coagulation cofactor, thereby preventing clotting.
CSS - PMS - CCE - PCS - General Science
Blood System
A blood sample allowed to clot before centrifugation yields:
A. Serum
B. Plasma with fibrinogen intact
C. Packed cells only
D. Bone marrow
Correct Answer: A
When blood clots, clotting factors such as fibrinogen are consumed; the remaining liquid is serum.
CSS - PMS - CCE - PCS - General Science
Blood System
Deoxygenated hemoglobin helps buffer blood by binding:
A. Hydrogen ions
B. Sodium only
C. Fibrin
D. Bilirubin
Correct Answer: A
Hemoglobin is an important intracellular buffer, especially in its deoxygenated form.
CSS - PMS - CCE - PCS - General Science
Blood System
The chloride shift is most closely associated with transport of:
A. Carbon dioxide
B. Oxygen only
C. Iron
D. Platelets
Correct Answer: A
The chloride shift facilitates carbon dioxide transport as plasma bicarbonate.
CSS - PMS - CCE - PCS - General Science
Blood System
Most bicarbonate produced in red blood cells leaves the cell in exchange for:
A. Chloride ions
B. Calcium ions
C. Iron ions
D. Phosphate crystals
Correct Answer: A
The chloride shift exchanges bicarbonate for chloride across the RBC membrane to maintain electroneutrality.
CSS - PMS - CCE - PCS - General Science
Blood System
Chronic residence at high altitude can increase red blood cell production mainly because of:
A. Reduced oxygen availability stimulating erythropoietin
B. Increased ABO antigen formation
C. Reduced plasma sodium only
D. Direct sunlight on marrow
Correct Answer: A
Lower oxygen tension at altitude stimulates renal erythropoietin and adaptive erythropoiesis.
CSS - PMS - CCE - PCS - General Science
Blood System
The term hematopoiesis means:
A. Formation of blood cells
B. Breakdown of hemoglobin
C. Clot dissolution
D. Blood grouping
Correct Answer: A
Hematopoiesis is the production and development of blood cells.
CSS - PMS - CCE - PCS - General Science
Blood System
After centrifuging anticoagulated whole blood, the bottom layer is mainly:
A. Plasma
B. Packed red blood cells
C. Serum only
D. Platelets only
Correct Answer: B
Red blood cells are the densest major component and settle at the bottom.
CSS - PMS - CCE - PCS - General Science
Blood System
After centrifuging anticoagulated whole blood, the uppermost layer is mainly:
A. Plasma
B. Packed red cells
C. Buffy coat only
D. Fibrin clot
Correct Answer: A
Plasma, being less dense than formed elements, forms the top layer.
CSS - PMS - CCE - PCS - General Science
Blood System
The buffy coat after centrifugation of anticoagulated blood mainly contains:
A. Leukocytes and platelets
B. Only erythrocytes
C. Only plasma proteins
D. Only fibrin
Correct Answer: A
The thin buffy coat between plasma and packed RBCs consists mainly of white cells and platelets.
CSS - PMS - CCE - PCS - General Science
Blood System
A marked rise in hematocrit generally tends to:
A. Increase blood viscosity
B. Decrease viscosity to zero
C. Prevent all clotting
D. Eliminate plasma proteins
Correct Answer: A
As the red-cell fraction rises, whole-blood viscosity usually increases.
CSS - PMS - CCE - PCS - General Science
Blood System
Blood viscosity is influenced strongly by the:
A. Hematocrit
B. ABO group alone
C. Skin color
D. Lens of the eye
Correct Answer: A
A higher proportion of red cells increases blood viscosity substantially.