BIO 201 Exam 2 – A&P I 2026 UPDATE | Straighterline 2026 Update • Verified Answers
✓ VERIFIED • 2026 UPDATE • 100% ACCURATE
BIO 201 Exam 2 – A&P; I 2026 UPDATE |
Straighterline
Actual Exam Questions & Verified Answers
with Detailed Rationales
Document Type: Exam (Elaborations)
Academic Year:
Total Questions: 50 Multiple Choice
Includes: Correct Answers + Full Rationales
Status: Verified & Updated for 2026
Exam (Elaborations) • Actual Questions & Rationales Page 1
,BIO 201 Exam 2 – A&P I 2026 UPDATE | Straighterline 2026 Update • Verified Answers
Questions & Verified Answers
1. Which type of bone cell is responsible for the resorption of bone tissue?
A. Osteoclast
B. Osteoblast
C. Osteocyte
D. Osteoprogenitor cell
Answer: A
Rationale: Osteoclasts are large, multinucleated cells that break down and resorb bone tissue to release
minerals into the blood. Applying this knowledge in clinical settings supports safe, evidence-based practice and
improves patient outcomes. This is an important clinical concept because selecting the correct answer (A)
requires understanding both the pathophysiology and the practical nursing implications.
2. The structural unit of compact bone is called the:
A. Osteon
B. Canaliculus
C. Trabeculae
D. Lamella
Answer: A
Rationale: The osteon (or Haversian system) is the fundamental functional unit of compact bone. This is an
important clinical concept because selecting the correct answer (A) requires understanding both the
pathophysiology and the practical nursing implications. Recognizing this principle allows the nurse to prioritize
care, anticipate complications, and provide accurate patient education.
3. Which hormone is released when blood calcium levels are too low?
A. Parathyroid Hormone (PTH)
B. Thyroxine
C. Calcitonin
D. Insulin
Answer: A
Rationale: Parathyroid Hormone (PTH) stimulates osteoclasts to break down bone and release calcium when
blood levels drop. Recognizing this principle allows the nurse to prioritize care, anticipate complications, and
provide accurate patient education. Exam questions often test the ability to distinguish this concept from closely
related distractors, making a clear rationale essential for mastery.
Exam (Elaborations) • Actual Questions & Rationales Page 2
, BIO 201 Exam 2 – A&P I 2026 UPDATE | Straighterline 2026 Update • Verified Answers
4. What is the name of the connective tissue that surrounds an entire muscle?
A. Endomysium
B. Perimysium
C. Fascia
D. Epimysium
Answer: D
Rationale: The epimysium is the outermost layer of dense irregular connective tissue that surrounds the whole
muscle. Exam questions often test the ability to distinguish this concept from closely related distractors, making
a clear rationale essential for mastery. Applying this knowledge in clinical settings supports safe,
evidence-based practice and improves patient outcomes.
5. In a sarcomere, the area that contains only thick filaments (myosin) is the:
A. I band
B. H zone
C. Z disc
D. A band
Answer: B
Rationale: The H zone is the center of the A band where there is no overlap with thin filaments, containing only
thick filaments. Recognizing this principle allows the nurse to prioritize care, anticipate complications, and
provide accurate patient education. Exam questions often test the ability to distinguish this concept from closely
related distractors, making a clear rationale essential for mastery.
6. During muscle contraction, calcium ions bind to which protein?
A. Tropomyosin
B. Troponin
C. Actin
D. Myosin
Answer: B
Rationale: Calcium binds to troponin, causing a conformational change that moves tropomyosin away from the
active sites on actin. Exam questions often test the ability to distinguish this concept from closely related
distractors, making a clear rationale essential for mastery. Applying this knowledge in clinical settings supports
safe, evidence-based practice and improves patient outcomes.
Exam (Elaborations) • Actual Questions & Rationales Page 3
✓ VERIFIED • 2026 UPDATE • 100% ACCURATE
BIO 201 Exam 2 – A&P; I 2026 UPDATE |
Straighterline
Actual Exam Questions & Verified Answers
with Detailed Rationales
Document Type: Exam (Elaborations)
Academic Year:
Total Questions: 50 Multiple Choice
Includes: Correct Answers + Full Rationales
Status: Verified & Updated for 2026
Exam (Elaborations) • Actual Questions & Rationales Page 1
,BIO 201 Exam 2 – A&P I 2026 UPDATE | Straighterline 2026 Update • Verified Answers
Questions & Verified Answers
1. Which type of bone cell is responsible for the resorption of bone tissue?
A. Osteoclast
B. Osteoblast
C. Osteocyte
D. Osteoprogenitor cell
Answer: A
Rationale: Osteoclasts are large, multinucleated cells that break down and resorb bone tissue to release
minerals into the blood. Applying this knowledge in clinical settings supports safe, evidence-based practice and
improves patient outcomes. This is an important clinical concept because selecting the correct answer (A)
requires understanding both the pathophysiology and the practical nursing implications.
2. The structural unit of compact bone is called the:
A. Osteon
B. Canaliculus
C. Trabeculae
D. Lamella
Answer: A
Rationale: The osteon (or Haversian system) is the fundamental functional unit of compact bone. This is an
important clinical concept because selecting the correct answer (A) requires understanding both the
pathophysiology and the practical nursing implications. Recognizing this principle allows the nurse to prioritize
care, anticipate complications, and provide accurate patient education.
3. Which hormone is released when blood calcium levels are too low?
A. Parathyroid Hormone (PTH)
B. Thyroxine
C. Calcitonin
D. Insulin
Answer: A
Rationale: Parathyroid Hormone (PTH) stimulates osteoclasts to break down bone and release calcium when
blood levels drop. Recognizing this principle allows the nurse to prioritize care, anticipate complications, and
provide accurate patient education. Exam questions often test the ability to distinguish this concept from closely
related distractors, making a clear rationale essential for mastery.
Exam (Elaborations) • Actual Questions & Rationales Page 2
, BIO 201 Exam 2 – A&P I 2026 UPDATE | Straighterline 2026 Update • Verified Answers
4. What is the name of the connective tissue that surrounds an entire muscle?
A. Endomysium
B. Perimysium
C. Fascia
D. Epimysium
Answer: D
Rationale: The epimysium is the outermost layer of dense irregular connective tissue that surrounds the whole
muscle. Exam questions often test the ability to distinguish this concept from closely related distractors, making
a clear rationale essential for mastery. Applying this knowledge in clinical settings supports safe,
evidence-based practice and improves patient outcomes.
5. In a sarcomere, the area that contains only thick filaments (myosin) is the:
A. I band
B. H zone
C. Z disc
D. A band
Answer: B
Rationale: The H zone is the center of the A band where there is no overlap with thin filaments, containing only
thick filaments. Recognizing this principle allows the nurse to prioritize care, anticipate complications, and
provide accurate patient education. Exam questions often test the ability to distinguish this concept from closely
related distractors, making a clear rationale essential for mastery.
6. During muscle contraction, calcium ions bind to which protein?
A. Tropomyosin
B. Troponin
C. Actin
D. Myosin
Answer: B
Rationale: Calcium binds to troponin, causing a conformational change that moves tropomyosin away from the
active sites on actin. Exam questions often test the ability to distinguish this concept from closely related
distractors, making a clear rationale essential for mastery. Applying this knowledge in clinical settings supports
safe, evidence-based practice and improves patient outcomes.
Exam (Elaborations) • Actual Questions & Rationales Page 3
