WGU D312 ANATOMY AND PHYSIOLOGY I WITH LAB OA EXAMINATION COMPLETE QUESTIONS AND DETAILED SOLUTIONS LATEST 2026 EDITION | ALREADY GRADED A+

WGU D312 ANATOMY AND PHYSIOLOGY I WITH LAB OA EXAMINATION
COMPLETE QUESTIONS AND DETAILED SOLUTIONS LATEST 2026 EDITION |
ALREADY GRADED A+

This comprehensive 300-question practice examination is meticulously designed
for students preparing for the WGU D312 Anatomy and Physiology I with Lab
Objective Assessment (OA). It covers all essential content areas including
levels of organization and homeostasis, anatomical terminology, cell biology
(structure, function, and division), histology (epithelial, connective,
muscle, and nervous tissues), the integumentary system, the skeletal system,
the muscular system, the nervous system, and laboratory applications. Each
question features multiple-choice, select-all-that-apply, or fill-in-the-blank
formats with a single correct answer and a detailed rationale explaining the
underlying anatomical and physiological concept. The content reflects current
WGU curriculum standards and tests the critical knowledge required to
successfully pass the D312 Objective Assessment.



SECTION 1: LEVELS OF ORGANIZATION AND HOMEOSTASIS (Questions 1-40)
Question 1:
What is the simplest level of structural organization in the human body?
a) Tissue level
b) Organ level
c) Chemical level
d) Cellular level
Answer: c) Chemical level.
Rationale: The chemical level is the simplest level, involving atoms and
molecules. Atoms combine to form molecules, which then form cellular
components. This level forms the foundation for all higher levels of
organization.

Question 2:
Which level of structural organization consists of similar cells that perform
a common function?

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,a) Chemical level
b) Cellular level
c) Tissue level
d) Organ level
Answer: c) Tissue level.
Rationale: Tissues are groups of similar cells that work together to perform
a specific function. The four primary tissue types are epithelial, connective,
muscle, and nervous tissue.

Question 3:
What is the correct order of organization in the human body, from simplest to
most complex?
a) Organ, tissue, cell, molecule, organ system
b) Atom, molecule, cell, tissue, organ, organ system, organism
c) Cell, molecule, organ system, organ, tissue
d) Tissue, cell, molecule, atom, organ
Answer: b) Atom, molecule, cell, tissue, organ, organ system, organism.
Rationale: The hierarchical organization of the human body begins with atoms,
which combine to form molecules. Molecules form cells, the smallest living
units. Cells organize into tissues, tissues into organs, organs into organ
systems, and organ systems work together to form an organism.

Question 4:
What is the study of the structure of body parts and their relationships to
one another?
a) Physiology
b) Anatomy
c) Cytology
d) Histology
Answer: b) Anatomy.
Rationale: Anatomy is the study of the structure of body parts and their
relationships to one another. Physiology is the study of the function of
body parts. Cytology is the study of cells, and histology is the study of
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,tissues.

Question 5:
What is the study of the function of body parts?
a) Anatomy
b) Physiology
c) Histology
d) Embryology
Answer: b) Physiology.
Rationale: Physiology is the study of the function of body parts and how
they work to maintain life. Anatomy and physiology are closely related,
as structure often determines function.

Question 6:
What is the term for the maintenance of a relatively stable internal
environment?
a) Metabolism
b) Homeostasis
c) Anabolism
d) Catabolism
Answer: b) Homeostasis.
Rationale: Homeostasis is the maintenance of a relatively stable internal
environment despite external changes. It is essential for the proper
functioning of cells and the body as a whole.

Question 7:
Which of the following is an example of negative feedback?
a) Uterine contractions during labor increasing oxytocin release
b) Blood clotting cascade
c) Regulation of blood glucose by insulin and glucagon
d) Depolarization of neurons during action potential
Answer: c) Regulation of blood glucose by insulin and glucagon.
Rationale: Negative feedback counteracts a change to return the variable
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, to its set point. Blood glucose regulation is a classic example: when
blood glucose rises, insulin is released to lower it; when it falls,
glucagon is released to raise it.

Question 8:
Which of the following is an example of positive feedback?
a) Regulation of body temperature
b) Blood pressure regulation
c) Blood clotting cascade
d) Blood glucose regulation
Answer: c) Blood clotting cascade.
Rationale: Positive feedback amplifies an initial change, pushing the
variable further from its set point. Blood clotting is a positive feedback
mechanism where the initial clot triggers more clotting until the vessel
is sealed.

Question 9:
What is the term for the sum of all chemical reactions in the body?
a) Homeostasis
b) Metabolism
c) Anabolism
d) Catabolism
Answer: b) Metabolism.
Rationale: Metabolism is the sum of all chemical reactions in the body.
It includes anabolism (building up) and catabolism (breaking down)
reactions.

Question 10:
What is the difference between anabolism and catabolism?
a) Anabolism breaks down molecules; catabolism builds them up
b) Anabolism builds up molecules; catabolism breaks them down
c) Both build up molecules
d) Both break down molecules
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