FUNDAMENTALS OF ANATOMY AND
PHYSIOLOGY
12TH EDITION
• AUTHOR(S)FREDERIC H. MARTINI;
JUDI L. NATH; EDWIN F.
BARTHOLOMEW
TEST BANK
1⃣
Reference
Ch. 1 — Levels of Organization: From Molecules to Organism
Stem
A lab partner argues that because molecules compose cells and
cells compose tissues, changing a single molecular interaction
can never affect whole-organism function. Using structure–
function reasoning, evaluate whether altering a membrane ion
channel molecule in cardiac muscle could plausibly change
organism-level function and explain the path of effect.
,Options
A. No — a single molecular change cannot scale to organism
effects because tissues compensate at higher levels.
B. Yes — altering a membrane ion channel can change cardiac
cell excitability, disrupting tissue contractility and thereby
organism circulation.
C. Only if the molecular change is widespread in many tissues;
isolated molecular changes remain local.
D. Yes — but only by directly changing the organism’s anatomy
(size/shape) rather than function.
Correct answer
B
Rationale — Correct (B)
Changing a membrane ion channel alters the excitability of
cardiac myocytes (cell level). That altered excitability impairs
coordinated contraction (tissue/organ level), reduces cardiac
output, and therefore affects systemic circulation (organism
level). This demonstrates how molecular structure determines
cell function and how that function scales through hierarchical
levels.
Rationale — Incorrect
A. Incorrect — tissues do not always fully compensate; certain
molecular changes produce emergent, system-level
dysfunction.
C. Incorrect — a single-molecule defect expressed in many cells
(e.g., channelopathy) can scale, but the option’s conditional
,phrasing ignores single-molecule defects that affect key cells.
D. Incorrect — functional changes (excitation, contractility) can
alter organism physiology without gross anatomical change.
Teaching point
Molecular changes can propagate upward through hierarchical
levels to alter whole-body physiology.
Citation
Martini, F. H., Nath, J. L., & Bartholomew, E. F. (2024).
Fundamentals of Anatomy and Physiology (12th ed.). Ch. 1.
2⃣
Reference
Ch. 1 — Anatomical Organization: Tissues and Organs
Stem
During a dissection lab, a student notes two adjacent regions of
muscle: one region shows tightly packed fibers oriented
longitudinally; the other has more loosely arranged, branching
fibers. Which reasoning best predicts a functional difference
between these regions based on structure–function
relationships?
Options
A. The longitudinally packed region generates more sustained
force; the branching region likely provides rapid,
multidirectional force.
B. Both regions will have identical contractile function because
, all muscle is made of the same cells.
C. The branching region must be connective tissue, not muscle,
because muscle fibers are never branching.
D. The longitudinal region cannot generate force; it only serves
as a passive support structure.
Correct answer
A
Rationale — Correct (A)
Fiber alignment influences force direction and distribution:
tightly packed, parallel fibers favor force generation along one
axis (sustained contraction), while branching or obliquely
arranged fibers permit force transmission in multiple directions
or complex contraction patterns. This is a direct structure–
function inference at the tissue level.
Rationale — Incorrect
B. Incorrect — muscle types and fiber orientation alter function;
not all muscle behaves identically.
C. Incorrect — some muscle types (cardiac) have branching
fibers; connective tissue has distinct extracellular features.
D. Incorrect — aligned muscle fibers are active contractile
elements, not passive supports.
Teaching point
Fiber orientation predicts direction and type of force
generation.
PHYSIOLOGY
12TH EDITION
• AUTHOR(S)FREDERIC H. MARTINI;
JUDI L. NATH; EDWIN F.
BARTHOLOMEW
TEST BANK
1⃣
Reference
Ch. 1 — Levels of Organization: From Molecules to Organism
Stem
A lab partner argues that because molecules compose cells and
cells compose tissues, changing a single molecular interaction
can never affect whole-organism function. Using structure–
function reasoning, evaluate whether altering a membrane ion
channel molecule in cardiac muscle could plausibly change
organism-level function and explain the path of effect.
,Options
A. No — a single molecular change cannot scale to organism
effects because tissues compensate at higher levels.
B. Yes — altering a membrane ion channel can change cardiac
cell excitability, disrupting tissue contractility and thereby
organism circulation.
C. Only if the molecular change is widespread in many tissues;
isolated molecular changes remain local.
D. Yes — but only by directly changing the organism’s anatomy
(size/shape) rather than function.
Correct answer
B
Rationale — Correct (B)
Changing a membrane ion channel alters the excitability of
cardiac myocytes (cell level). That altered excitability impairs
coordinated contraction (tissue/organ level), reduces cardiac
output, and therefore affects systemic circulation (organism
level). This demonstrates how molecular structure determines
cell function and how that function scales through hierarchical
levels.
Rationale — Incorrect
A. Incorrect — tissues do not always fully compensate; certain
molecular changes produce emergent, system-level
dysfunction.
C. Incorrect — a single-molecule defect expressed in many cells
(e.g., channelopathy) can scale, but the option’s conditional
,phrasing ignores single-molecule defects that affect key cells.
D. Incorrect — functional changes (excitation, contractility) can
alter organism physiology without gross anatomical change.
Teaching point
Molecular changes can propagate upward through hierarchical
levels to alter whole-body physiology.
Citation
Martini, F. H., Nath, J. L., & Bartholomew, E. F. (2024).
Fundamentals of Anatomy and Physiology (12th ed.). Ch. 1.
2⃣
Reference
Ch. 1 — Anatomical Organization: Tissues and Organs
Stem
During a dissection lab, a student notes two adjacent regions of
muscle: one region shows tightly packed fibers oriented
longitudinally; the other has more loosely arranged, branching
fibers. Which reasoning best predicts a functional difference
between these regions based on structure–function
relationships?
Options
A. The longitudinally packed region generates more sustained
force; the branching region likely provides rapid,
multidirectional force.
B. Both regions will have identical contractile function because
, all muscle is made of the same cells.
C. The branching region must be connective tissue, not muscle,
because muscle fibers are never branching.
D. The longitudinal region cannot generate force; it only serves
as a passive support structure.
Correct answer
A
Rationale — Correct (A)
Fiber alignment influences force direction and distribution:
tightly packed, parallel fibers favor force generation along one
axis (sustained contraction), while branching or obliquely
arranged fibers permit force transmission in multiple directions
or complex contraction patterns. This is a direct structure–
function inference at the tissue level.
Rationale — Incorrect
B. Incorrect — muscle types and fiber orientation alter function;
not all muscle behaves identically.
C. Incorrect — some muscle types (cardiac) have branching
fibers; connective tissue has distinct extracellular features.
D. Incorrect — aligned muscle fibers are active contractile
elements, not passive supports.
Teaching point
Fiber orientation predicts direction and type of force
generation.
