WGU D312 Anatomy and Physiology I Objective
Assessment 2025/2026 | Practice Questions,
CORRECT ANSWERs & Detailed Rationales –
Latest Version
WGU D312 – Anatomy and Physiology I
Objective Assessment | 400 Practice Questions with CORRECT ANSWER &
Detailed RATIONALE
KEY: CORRECT ANSWERs are marked with and bold
UNIT 1: INTRODUCTION TO THE HUMAN BODY & ANATOMICAL TERMINOLOGY
Q1. Which anatomical term describes the front surface of the human body?
A. Posterior B. Lateral C. Medial D. Anterior E. Inferior
RATIONALE: Anterior (ventral) refers to the front of the body. Posterior (dorsal) refers to
the back. These directional terms are fundamental to anatomical description.
Q2. A cut that divides the body into left and right portions is called a:
A. Transverse plane B. Frontal plane C. Sagittal plane D. Oblique plane E. Coronal
plane
RATIONALE: The sagittal plane divides the body into left and right portions. A
midsagittal (median) plane divides it into equal halves. The frontal/coronal plane divides
front from back, and the transverse plane divides superior from inferior.
Q3. Which term correctly describes the relationship of the knee to the hip?
A. Superior B. Proximal C. Medial D. Inferior E. Lateral
RATIONALE: Inferior means toward the lower part of the body or below a reference
point. The knee is below (inferior to) the hip in standard anatomical position.
Q4. The thoracic cavity is separated from the abdominopelvic cavity by the:
,A. Pleura B. Pericardium C. Diaphragm D. Peritoneum E. Mediastinum
RATIONALE: The diaphragm is the dome-shaped muscle that physically separates the
thoracic cavity above from the abdominopelvic cavity below. It also plays the primary
role in breathing.
Q5. Which body cavity contains the heart and lungs?
A. Abdominal cavity B. Thoracic cavity C. Pelvic cavity D. Cranial cavity E. Spinal
cavity
RATIONALE: The thoracic cavity is enclosed by the rib cage and contains the lungs (in
pleural cavities) and the heart (in the pericardial cavity within the mediastinum).
Q6. The study of the functions of the human body is called:
A. Anatomy B. Cytology C. Histology D. Physiology E. Pathology
RATIONALE: Physiology is the science that studies how the body and its parts function.
Anatomy focuses on structure, histology on tissues, and cytology on cells.
Q7. Which plane divides the body into superior and inferior portions?
A. Sagittal B. Coronal C. Frontal D. Transverse E. Midsagittal
RATIONALE: The transverse (horizontal) plane divides the body into upper (superior)
and lower (inferior) sections. It is also called a cross-sectional plane.
Q8. In anatomical position, the palms of the hands face:
A. Posteriorly B. Anteriorly C. Medially D. Laterally E. Inferiorly
RATIONALE: In standard anatomical position, the body stands erect, eyes forward, feet
slightly apart, and arms at the sides with palms facing anteriorly (forward). This is the
standard reference for all directional terms.
Q9. The term "medial" refers to structures that are:
,A. Closer to the midline of the body B. Farther from the midline of the body C.
Closer to the origin of a limb D. Farther from the surface E. Above a reference point
RATIONALE: Medial means toward the midline of the body. Lateral means away from
the midline. For example, the nose is medial to the eyes.
Q10. Which of the following is the most basic level of structural organization in
the body?
A. Chemical level B. Cellular level C. Tissue level D. Organ level E. Organism level
RATIONALE: The chemical level is the most basic, involving atoms and molecules.
Above this are the cellular, tissue, organ, organ system, and organism levels, in order of
increasing complexity.
Q11. The pericardial cavity houses the:
A. Lungs B. Liver C. Heart D. Kidneys E. Stomach
RATIONALE: The pericardial cavity is the fluid-filled space surrounding the heart. It is
located within the mediastinum, the central portion of the thoracic cavity.
Q12. Which organ system is primarily responsible for regulating body
temperature, protecting against pathogens, and preventing water loss?
A. Nervous system B. Immune system C. Integumentary system D. Endocrine
system E. Lymphatic system
RATIONALE: The integumentary system (skin, hair, nails, glands) serves as the body's
first line of defense against environmental hazards, regulates temperature, and prevents
dehydration.
Q13. The term "distal" when applied to a limb means:
A. Closer to the trunk B. Farther from the point of attachment C. On the same
side of the body D. Toward the back E. On the lateral surface
RATIONALE: Distal refers to a position farther from the point of origin or attachment.
For example, the fingers are distal to the wrist. Proximal is the opposite, meaning closer
to the point of attachment.
, Q14. Which of the following describes the body's ability to maintain stable
internal conditions?
A. Metabolism B. Catabolism C. Homeostasis D. Anabolism E. Differentiation
RATIONALE: Homeostasis is the physiological process by which a living organism
maintains a stable internal environment despite changes in external conditions. Blood
pressure, pH, and temperature regulation are all examples.
Q15. The right upper quadrant of the abdominopelvic region contains the:
A. Liver and gallbladder B. Spleen and stomach C. Appendix and cecum D.
Sigmoid colon E. Urinary bladder
RATIONALE: The right upper quadrant (RUQ) contains the liver, gallbladder, right
kidney, and part of the large intestine. The left upper quadrant contains the stomach and
spleen.
Q16. Which feedback mechanism is responsible for maintaining most
homeostatic processes in the body?
A. Positive feedback B. Negative feedback C. Feed-forward regulation D.
Hormonal amplification E. Neural override
RATIONALE: Negative feedback loops counteract a change by producing a response
that opposes the stimulus, restoring homeostasis. Examples include body temperature
regulation and blood glucose control.
Q17. A positive feedback loop:
A. Counteracts changes in the body B. Returns the body to homeostasis C. Amplifies
the original stimulus D. Inhibits receptor activity E. Maintains blood pressure
RATIONALE: Positive feedback amplifies or enhances the original stimulus, moving the
body further from homeostasis. Examples include childbirth contractions (oxytocin
release) and blood clotting.
Q18. The epigastric region is located:
Assessment 2025/2026 | Practice Questions,
CORRECT ANSWERs & Detailed Rationales –
Latest Version
WGU D312 – Anatomy and Physiology I
Objective Assessment | 400 Practice Questions with CORRECT ANSWER &
Detailed RATIONALE
KEY: CORRECT ANSWERs are marked with and bold
UNIT 1: INTRODUCTION TO THE HUMAN BODY & ANATOMICAL TERMINOLOGY
Q1. Which anatomical term describes the front surface of the human body?
A. Posterior B. Lateral C. Medial D. Anterior E. Inferior
RATIONALE: Anterior (ventral) refers to the front of the body. Posterior (dorsal) refers to
the back. These directional terms are fundamental to anatomical description.
Q2. A cut that divides the body into left and right portions is called a:
A. Transverse plane B. Frontal plane C. Sagittal plane D. Oblique plane E. Coronal
plane
RATIONALE: The sagittal plane divides the body into left and right portions. A
midsagittal (median) plane divides it into equal halves. The frontal/coronal plane divides
front from back, and the transverse plane divides superior from inferior.
Q3. Which term correctly describes the relationship of the knee to the hip?
A. Superior B. Proximal C. Medial D. Inferior E. Lateral
RATIONALE: Inferior means toward the lower part of the body or below a reference
point. The knee is below (inferior to) the hip in standard anatomical position.
Q4. The thoracic cavity is separated from the abdominopelvic cavity by the:
,A. Pleura B. Pericardium C. Diaphragm D. Peritoneum E. Mediastinum
RATIONALE: The diaphragm is the dome-shaped muscle that physically separates the
thoracic cavity above from the abdominopelvic cavity below. It also plays the primary
role in breathing.
Q5. Which body cavity contains the heart and lungs?
A. Abdominal cavity B. Thoracic cavity C. Pelvic cavity D. Cranial cavity E. Spinal
cavity
RATIONALE: The thoracic cavity is enclosed by the rib cage and contains the lungs (in
pleural cavities) and the heart (in the pericardial cavity within the mediastinum).
Q6. The study of the functions of the human body is called:
A. Anatomy B. Cytology C. Histology D. Physiology E. Pathology
RATIONALE: Physiology is the science that studies how the body and its parts function.
Anatomy focuses on structure, histology on tissues, and cytology on cells.
Q7. Which plane divides the body into superior and inferior portions?
A. Sagittal B. Coronal C. Frontal D. Transverse E. Midsagittal
RATIONALE: The transverse (horizontal) plane divides the body into upper (superior)
and lower (inferior) sections. It is also called a cross-sectional plane.
Q8. In anatomical position, the palms of the hands face:
A. Posteriorly B. Anteriorly C. Medially D. Laterally E. Inferiorly
RATIONALE: In standard anatomical position, the body stands erect, eyes forward, feet
slightly apart, and arms at the sides with palms facing anteriorly (forward). This is the
standard reference for all directional terms.
Q9. The term "medial" refers to structures that are:
,A. Closer to the midline of the body B. Farther from the midline of the body C.
Closer to the origin of a limb D. Farther from the surface E. Above a reference point
RATIONALE: Medial means toward the midline of the body. Lateral means away from
the midline. For example, the nose is medial to the eyes.
Q10. Which of the following is the most basic level of structural organization in
the body?
A. Chemical level B. Cellular level C. Tissue level D. Organ level E. Organism level
RATIONALE: The chemical level is the most basic, involving atoms and molecules.
Above this are the cellular, tissue, organ, organ system, and organism levels, in order of
increasing complexity.
Q11. The pericardial cavity houses the:
A. Lungs B. Liver C. Heart D. Kidneys E. Stomach
RATIONALE: The pericardial cavity is the fluid-filled space surrounding the heart. It is
located within the mediastinum, the central portion of the thoracic cavity.
Q12. Which organ system is primarily responsible for regulating body
temperature, protecting against pathogens, and preventing water loss?
A. Nervous system B. Immune system C. Integumentary system D. Endocrine
system E. Lymphatic system
RATIONALE: The integumentary system (skin, hair, nails, glands) serves as the body's
first line of defense against environmental hazards, regulates temperature, and prevents
dehydration.
Q13. The term "distal" when applied to a limb means:
A. Closer to the trunk B. Farther from the point of attachment C. On the same
side of the body D. Toward the back E. On the lateral surface
RATIONALE: Distal refers to a position farther from the point of origin or attachment.
For example, the fingers are distal to the wrist. Proximal is the opposite, meaning closer
to the point of attachment.
, Q14. Which of the following describes the body's ability to maintain stable
internal conditions?
A. Metabolism B. Catabolism C. Homeostasis D. Anabolism E. Differentiation
RATIONALE: Homeostasis is the physiological process by which a living organism
maintains a stable internal environment despite changes in external conditions. Blood
pressure, pH, and temperature regulation are all examples.
Q15. The right upper quadrant of the abdominopelvic region contains the:
A. Liver and gallbladder B. Spleen and stomach C. Appendix and cecum D.
Sigmoid colon E. Urinary bladder
RATIONALE: The right upper quadrant (RUQ) contains the liver, gallbladder, right
kidney, and part of the large intestine. The left upper quadrant contains the stomach and
spleen.
Q16. Which feedback mechanism is responsible for maintaining most
homeostatic processes in the body?
A. Positive feedback B. Negative feedback C. Feed-forward regulation D.
Hormonal amplification E. Neural override
RATIONALE: Negative feedback loops counteract a change by producing a response
that opposes the stimulus, restoring homeostasis. Examples include body temperature
regulation and blood glucose control.
Q17. A positive feedback loop:
A. Counteracts changes in the body B. Returns the body to homeostasis C. Amplifies
the original stimulus D. Inhibits receptor activity E. Maintains blood pressure
RATIONALE: Positive feedback amplifies or enhances the original stimulus, moving the
body further from homeostasis. Examples include childbirth contractions (oxytocin
release) and blood clotting.
Q18. The epigastric region is located:
