CHAMBERLAIN UNIVERSITY
B I O S 2 5 5 • A N AT O M Y & P H Y S I O L O G Y I I I
Exam 2
Complete Guide
Blood & Hematology · Cardiovascular · Lymphatic & Immune
Respiratory · Digestive Systems
T O TA L SECTIONS F O R M AT EDITION
QUESTIONS
100 6 MCQ (A–D) 2026–27
EXAM COVERAGE
Q1–Q20 Blood & Hematology Q21–Q40 CV: Heart
Q41–Q55 CV: Vessels & Hemodynamics Q56–Q70 Lymphatic & Immune
Q71–Q85 Respiratory System Q86–Q100 Digestive System
GRADE A • 100% CORRECT • VERIFIED Chamberlain University
Comprehensive rationales · Clinical correlations · A&P III standards BIOS255 — Exam 2
,BIOS 255 — Anatomy & Physiology III Exam 2 — Complete Guide
BIOS 255 — Anatomy & Physiology III
Exam 2 — Complete Guide · Edition
Course: BIOS255 Anatomy & Physiology III | Exam: Exam 2 | Questions: 100 (Sections 1–6) | Format:
Multiple Choice (A–D), single best answer | Cognitive Mix: 30% recall, 50% application, 20% analysis |
Question Types: 65% scenario/application, 25% mechanism, 10% structural identification
How to Read Each Item
Each question lists four options (A–D). The single correct option is marked [CORRECT] inline. The line Correct Answer:
X restates the correct option, followed by a Rationale box explaining the anatomy, physiology, and clinical reasoning (why
the correct option is right and why the distractors are wrong).
Section 1: Blood and Hematology
Blood composition · Hematopoiesis · RBCs · WBCs · Platelets · Hemostasis · Blood typing · Blood disorders · Q1–Q20
Q1. A peripheral blood smear from a dehydrated patient shows normal cell morphology, but plasma
analysis reveals elevated total protein with a normal albumin-to-globulin ratio. Which component
contributes the LARGEST percentage to plasma volume?
A Plasma proteins, primarily albumin
B Electrolytes such as Na+ and Cl−
C Water, accounting for approximately 55% of whole blood [CORRECT]
D Nutrients including glucose and amino acids
Correct Answer: C. Water, accounting for approximately 55% of whole blood
Rationale: Plasma is approximately 90% water by volume, with proteins (albumin, globulins, fibrinogen)
constituting only about 8% and other solutes (electrolytes, nutrients, hormones, gases) making up the remainder.
Water therefore contributes the largest fraction of plasma and roughly 55% of whole blood when separated from
formed elements. Option A is incorrect because proteins, while osmotically important, are only ~8% of plasma; B
and D represent much smaller solute fractions.
Q2. A 45-year-old male living at high altitude (4,500 m) presents with an elevated hematocrit of 58%.
Which renal mechanism best explains the increased erythropoiesis?
A Direct stimulation of bone marrow stem cells by hypoxia-inducible factor 1-alpha (HIF-1α)
B Release of erythropoietin (EPO) from peritubular interstitial fibroblasts of the kidney
[CORRECT]
C Increased secretion of renin from juxtaglomerular cells activating thrombopoietin
D Hepatic production of erythropoietin in response to tissue hypoxia
Chamberlain University · 2026/2027 Edition Page 1
,BIOS 255 — Anatomy & Physiology III Exam 2 — Complete Guide
Correct Answer: B. Release of erythropoietin (EPO) from peritubular interstitial fibroblasts of the kidney
Rationale: Hypoxia at high altitude is sensed by peritubular interstitial fibroblasts in the renal cortex, which
upregulate HIF-1α and consequently increase erythropoietin (EPO) synthesis. EPO travels to the red bone marrow
and stimulates CFU-E progenitors to proliferate and mature into reticulocytes, raising hematocrit. The liver does
produce small amounts of EPO in fetal life but is not the primary adult source, ruling out D, and
renin/thrombopoietin are unrelated to erythropoiesis.
Q3. A 62-year-old woman with a history of subtotal gastrectomy presents with fatigue, glossitis, and
paresthesias. Labs reveal MCV 115 fL, hemoglobin 8.2 g/dL, and hypersegmented neutrophils. Which
mechanism most directly accounts for the macrocytic anemia?
A Iron deficiency impairing heme synthesis
B Intrinsic factor deficiency causing impaired vitamin B12 absorption [CORRECT]
C Folate receptor autoantibody production by gastric parietal cells
D Erythropoietin deficiency secondary to chronic kidney disease
Correct Answer: B. Intrinsic factor deficiency causing impaired vitamin B12 absorption
Rationale: Subtotal gastrectomy removes parietal cells that secrete intrinsic factor (IF), which is required for
vitamin B12 absorption in the terminal ileum. Without IF, B12 deficiency develops, causing megaloblastic anemia
with elevated MCV, hypersegmented neutrophils, and neurological symptoms such as paresthesias. Iron deficiency
causes microcytic anemia (low MCV), and EPO deficiency produces normocytic anemia of chronic kidney disease.
Folate deficiency can produce a similar picture but is not directly tied to gastrectomy.
Q4. A hemoglobin molecule contains four polypeptide chains (two α and two β subunits) and four
heme groups. How many oxygen molecules can one fully saturated hemoglobin molecule transport?
A 1
B 2
C 4 [CORRECT]
D 8
Correct Answer: C. 4
Rationale: Each of the four globin subunits binds one heme group, and each heme contains a single Fe2+ ion that
coordinates one O2 molecule. Therefore, a fully saturated hemoglobin tetramer carries four O2 molecules (one per
heme). Options A, B, and D reflect common errors: 2 ignores the αβ dimer doubling, and 8 wrongly assumes two
oxygens per heme, which is impossible because each iron has only one available coordination site.
Q5. A 28-year-old man returns from a camping trip with abdominal cramping, diarrhea, and a WBC
differential showing 18% eosinophils (normal 1-4%). Which physiological role of eosinophils explains
this elevation?
Chamberlain University · 2026/2027 Edition Page 2
, BIOS 255 — Anatomy & Physiology III Exam 2 — Complete Guide
A Phagocytosis of encapsulated bacteria via complement receptor 1
B Release of major basic protein and reactive oxygen species to attack parasitic helminths
[CORRECT]
C Production of histamine and heparin during immediate hypersensitivity
D Antigen presentation to CD4+ T-helper cells via MHC class II
Correct Answer: B. Release of major basic protein and reactive oxygen species to attack parasitic helminths
Rationale: Eosinophils are specialized to combat large multicellular parasites, particularly helminths, which cannot
be phagocytosed. They attach to IgE- or IgG-coated parasites and release major basic protein, eosinophil cationic
protein, and reactive oxygen species that damage the parasite tegument. The camping history and GI symptoms
strongly suggest parasitic infection. Option C describes basophils; A describes neutrophils; D describes
macrophages/dendritic cells.
Q6. A patient with type A blood (genotype AO) is mistakenly transfused with type AB packed red cells.
Within 30 minutes she develops fever, flank pain, hypotension, and hemoglobinuria. What is the
PRIMARY immunological mechanism of this acute hemolytic transfusion reaction?
A IgM anti-B antibodies naturally present in the recipient agglutinate and lyse donor RBCs via
complement activation [CORRECT]
B IgG anti-D antibodies cross the placenta and attack fetal D-positive cells
C Cytotoxic T lymphocytes recognize foreign MHC class I on donor erythrocytes
D Donor anti-A antibodies in the plasma attack recipient erythrocytes
Correct Answer: A. IgM anti-B antibodies naturally present in the recipient agglutinate and lyse donor
RBCs via complement activation
Rationale: Type A individuals naturally produce IgM anti-B antibodies because environmental antigens resemble B
antigen. When AB donor cells (carrying B antigen) are infused, recipient IgM anti-B binds and activates the classical
complement cascade (C1q → MAC), causing intravascular hemolysis, hemoglobinuria, hypotension, and DIC risk.
IgG anti-D causes hemolytic disease of the newborn, not transfusion reaction; RBCs lack MHC; and donor anti-A in
packed cells is minimal.
Q7. A researcher studies hemostasis after a clean scalpel incision. Place the following events in correct
temporal sequence: (1) platelet adhesion, (2) vascular spasm, (3) fibrinolysis, (4) coagulation cascade,
(5) platelet plug formation.
A 2 → 1 → 5 → 4 → 3 [CORRECT]
B 1→2→5→3→4
C 2→5→1→3→4
D 4→1→5→2→3
Correct Answer: A. 2 → 1 → 5 → 4 → 3
Chamberlain University · 2026/2027 Edition Page 3
B I O S 2 5 5 • A N AT O M Y & P H Y S I O L O G Y I I I
Exam 2
Complete Guide
Blood & Hematology · Cardiovascular · Lymphatic & Immune
Respiratory · Digestive Systems
T O TA L SECTIONS F O R M AT EDITION
QUESTIONS
100 6 MCQ (A–D) 2026–27
EXAM COVERAGE
Q1–Q20 Blood & Hematology Q21–Q40 CV: Heart
Q41–Q55 CV: Vessels & Hemodynamics Q56–Q70 Lymphatic & Immune
Q71–Q85 Respiratory System Q86–Q100 Digestive System
GRADE A • 100% CORRECT • VERIFIED Chamberlain University
Comprehensive rationales · Clinical correlations · A&P III standards BIOS255 — Exam 2
,BIOS 255 — Anatomy & Physiology III Exam 2 — Complete Guide
BIOS 255 — Anatomy & Physiology III
Exam 2 — Complete Guide · Edition
Course: BIOS255 Anatomy & Physiology III | Exam: Exam 2 | Questions: 100 (Sections 1–6) | Format:
Multiple Choice (A–D), single best answer | Cognitive Mix: 30% recall, 50% application, 20% analysis |
Question Types: 65% scenario/application, 25% mechanism, 10% structural identification
How to Read Each Item
Each question lists four options (A–D). The single correct option is marked [CORRECT] inline. The line Correct Answer:
X restates the correct option, followed by a Rationale box explaining the anatomy, physiology, and clinical reasoning (why
the correct option is right and why the distractors are wrong).
Section 1: Blood and Hematology
Blood composition · Hematopoiesis · RBCs · WBCs · Platelets · Hemostasis · Blood typing · Blood disorders · Q1–Q20
Q1. A peripheral blood smear from a dehydrated patient shows normal cell morphology, but plasma
analysis reveals elevated total protein with a normal albumin-to-globulin ratio. Which component
contributes the LARGEST percentage to plasma volume?
A Plasma proteins, primarily albumin
B Electrolytes such as Na+ and Cl−
C Water, accounting for approximately 55% of whole blood [CORRECT]
D Nutrients including glucose and amino acids
Correct Answer: C. Water, accounting for approximately 55% of whole blood
Rationale: Plasma is approximately 90% water by volume, with proteins (albumin, globulins, fibrinogen)
constituting only about 8% and other solutes (electrolytes, nutrients, hormones, gases) making up the remainder.
Water therefore contributes the largest fraction of plasma and roughly 55% of whole blood when separated from
formed elements. Option A is incorrect because proteins, while osmotically important, are only ~8% of plasma; B
and D represent much smaller solute fractions.
Q2. A 45-year-old male living at high altitude (4,500 m) presents with an elevated hematocrit of 58%.
Which renal mechanism best explains the increased erythropoiesis?
A Direct stimulation of bone marrow stem cells by hypoxia-inducible factor 1-alpha (HIF-1α)
B Release of erythropoietin (EPO) from peritubular interstitial fibroblasts of the kidney
[CORRECT]
C Increased secretion of renin from juxtaglomerular cells activating thrombopoietin
D Hepatic production of erythropoietin in response to tissue hypoxia
Chamberlain University · 2026/2027 Edition Page 1
,BIOS 255 — Anatomy & Physiology III Exam 2 — Complete Guide
Correct Answer: B. Release of erythropoietin (EPO) from peritubular interstitial fibroblasts of the kidney
Rationale: Hypoxia at high altitude is sensed by peritubular interstitial fibroblasts in the renal cortex, which
upregulate HIF-1α and consequently increase erythropoietin (EPO) synthesis. EPO travels to the red bone marrow
and stimulates CFU-E progenitors to proliferate and mature into reticulocytes, raising hematocrit. The liver does
produce small amounts of EPO in fetal life but is not the primary adult source, ruling out D, and
renin/thrombopoietin are unrelated to erythropoiesis.
Q3. A 62-year-old woman with a history of subtotal gastrectomy presents with fatigue, glossitis, and
paresthesias. Labs reveal MCV 115 fL, hemoglobin 8.2 g/dL, and hypersegmented neutrophils. Which
mechanism most directly accounts for the macrocytic anemia?
A Iron deficiency impairing heme synthesis
B Intrinsic factor deficiency causing impaired vitamin B12 absorption [CORRECT]
C Folate receptor autoantibody production by gastric parietal cells
D Erythropoietin deficiency secondary to chronic kidney disease
Correct Answer: B. Intrinsic factor deficiency causing impaired vitamin B12 absorption
Rationale: Subtotal gastrectomy removes parietal cells that secrete intrinsic factor (IF), which is required for
vitamin B12 absorption in the terminal ileum. Without IF, B12 deficiency develops, causing megaloblastic anemia
with elevated MCV, hypersegmented neutrophils, and neurological symptoms such as paresthesias. Iron deficiency
causes microcytic anemia (low MCV), and EPO deficiency produces normocytic anemia of chronic kidney disease.
Folate deficiency can produce a similar picture but is not directly tied to gastrectomy.
Q4. A hemoglobin molecule contains four polypeptide chains (two α and two β subunits) and four
heme groups. How many oxygen molecules can one fully saturated hemoglobin molecule transport?
A 1
B 2
C 4 [CORRECT]
D 8
Correct Answer: C. 4
Rationale: Each of the four globin subunits binds one heme group, and each heme contains a single Fe2+ ion that
coordinates one O2 molecule. Therefore, a fully saturated hemoglobin tetramer carries four O2 molecules (one per
heme). Options A, B, and D reflect common errors: 2 ignores the αβ dimer doubling, and 8 wrongly assumes two
oxygens per heme, which is impossible because each iron has only one available coordination site.
Q5. A 28-year-old man returns from a camping trip with abdominal cramping, diarrhea, and a WBC
differential showing 18% eosinophils (normal 1-4%). Which physiological role of eosinophils explains
this elevation?
Chamberlain University · 2026/2027 Edition Page 2
, BIOS 255 — Anatomy & Physiology III Exam 2 — Complete Guide
A Phagocytosis of encapsulated bacteria via complement receptor 1
B Release of major basic protein and reactive oxygen species to attack parasitic helminths
[CORRECT]
C Production of histamine and heparin during immediate hypersensitivity
D Antigen presentation to CD4+ T-helper cells via MHC class II
Correct Answer: B. Release of major basic protein and reactive oxygen species to attack parasitic helminths
Rationale: Eosinophils are specialized to combat large multicellular parasites, particularly helminths, which cannot
be phagocytosed. They attach to IgE- or IgG-coated parasites and release major basic protein, eosinophil cationic
protein, and reactive oxygen species that damage the parasite tegument. The camping history and GI symptoms
strongly suggest parasitic infection. Option C describes basophils; A describes neutrophils; D describes
macrophages/dendritic cells.
Q6. A patient with type A blood (genotype AO) is mistakenly transfused with type AB packed red cells.
Within 30 minutes she develops fever, flank pain, hypotension, and hemoglobinuria. What is the
PRIMARY immunological mechanism of this acute hemolytic transfusion reaction?
A IgM anti-B antibodies naturally present in the recipient agglutinate and lyse donor RBCs via
complement activation [CORRECT]
B IgG anti-D antibodies cross the placenta and attack fetal D-positive cells
C Cytotoxic T lymphocytes recognize foreign MHC class I on donor erythrocytes
D Donor anti-A antibodies in the plasma attack recipient erythrocytes
Correct Answer: A. IgM anti-B antibodies naturally present in the recipient agglutinate and lyse donor
RBCs via complement activation
Rationale: Type A individuals naturally produce IgM anti-B antibodies because environmental antigens resemble B
antigen. When AB donor cells (carrying B antigen) are infused, recipient IgM anti-B binds and activates the classical
complement cascade (C1q → MAC), causing intravascular hemolysis, hemoglobinuria, hypotension, and DIC risk.
IgG anti-D causes hemolytic disease of the newborn, not transfusion reaction; RBCs lack MHC; and donor anti-A in
packed cells is minimal.
Q7. A researcher studies hemostasis after a clean scalpel incision. Place the following events in correct
temporal sequence: (1) platelet adhesion, (2) vascular spasm, (3) fibrinolysis, (4) coagulation cascade,
(5) platelet plug formation.
A 2 → 1 → 5 → 4 → 3 [CORRECT]
B 1→2→5→3→4
C 2→5→1→3→4
D 4→1→5→2→3
Correct Answer: A. 2 → 1 → 5 → 4 → 3
Chamberlain University · 2026/2027 Edition Page 3
