WGU D312 - Anatomy & Physiology I
questions well answered 2025/2026
What quadrant includes the left lobe of the liver, stomach, pancreas, and portions of the small
and large intestines? - ANS ✔✔Left upper quadrant (LUQ)
Which part of the plasma membrane binds a specific molecule outside the cell? - ANS
✔✔Receptor
A receptor is a type of recognition protein that can selectively bind a specific molecule outside
the cell, and this binding induces a chemical reaction within the cell.
What does it mean if an anatomical structure is caudal? - ANS ✔✔If an anatomical structure is
described as caudal, it means it is located towards the tail or lower part of the body. In humans,
this typically refers to a position closer to the feet or the lower end of the spine.
For example, the legs are caudal to the arms, meaning they are situated lower on the body
compared to the arms.
What is the role of an effector in a negative feedback system? - ANS ✔✔In a negative feedback
system, the effector plays a crucial role in maintaining homeostasis by carrying out the response
to a stimulus. Here's how it works:
Detection: A receptor detects a change in a physiological variable (e.g., temperature, blood
sugar levels).
Signal Processing: The control center (often the brain or endocrine glands) processes this
information and determines the appropriate response.
Action: The effector enacts the response to counteract the initial change and bring the variable
back to its set point.
For example, if your body temperature drops, the effector (such as muscles shivering) generates
heat to raise your body temperature back to normal.
,What is the correct order of the epidermis layer arranged from deep to superficial? - ANS ✔✔1.
Stratum basale (or stratum germinativum)
2. Stratum spinosum
3. Stratum granulosum
4. Stratum lucidum (only present in thick skin, such as the palms and soles)
5. Stratum corneum
Which skin layer contains Langerhans cells? - ANS ✔✔Langerhans cells are primarily found in
the stratum spinosum layer of the epidermis. These cells play a key role in the skin's immune
defense by acting as antigen-presenting cells, which help detect and fight pathogens.
Which degree of burn affects the underlying bones and muscles? - ANS ✔✔Fourth-degree
burns are the most severe and affect not only all layers of the skin but also the underlying
bones, muscles, and tendons. These burns often appear charred or white and are typically
painless because the nerve endings are destroyed.
Which part of the long bone has an epiphyseal line? - ANS ✔✔The epiphyseal line is located at
the junction between the diaphysis (the shaft or central part of the bone) and the epiphysis (the
end part of the bone) in long bones. This line is a remnant of the epiphyseal plate (growth plate)
and indicates that the bone has completed its growth in length.
Which suture is present between the left and right parietal lobes? - ANS ✔✔The suture present
between the left and right parietal lobes is the sagittal suture. This suture runs along the midline
of the skull, connecting the two parietal bones.
Which two bones form the pectoral girdle? - ANS ✔✔The pectoral girdle, also known as the
shoulder girdle, is formed by two bones: the clavicle (collarbone) and the scapula (shoulder
blade). These bones work together to connect the upper limb to the axial skeleton and provide
a wide range of motion for the shoulder and arm.
,What are the periodic invaginations in sarcolemma called? - ANS ✔✔The periodic invaginations
in the sarcolemma are called T-tubules (transverse tubules). These structures play a crucial role
in conducting electrical impulses from the surface of the muscle fiber to its interior, ensuring
that the muscle contracts efficiently and uniformly.
Which medially placed group of muscles is part of the erector spinae? - ANS ✔✔The spinalis
muscles are the most medially placed group within the erector spinae muscle group. These
muscles are located closest to the spine and are responsible for extending and laterally flexing
the cervical and thoracic regions of the spine.
Which thigh muscle is situated below the adductor longus? - ANS ✔✔The muscle situated
below the adductor longus is the adductor magnus. This muscle is a large, triangular muscle
located in the medial compartment of the thigh and plays a significant role in adducting and
medially rotating the thigh
What is the role of oligodendrocytes? - ANS ✔✔Oligodendrocytes play a crucial role in the
central nervous system (CNS) by producing the myelin sheath that insulates axons. This
myelination is essential for the efficient transmission of electrical impulses along nerve fibers,
which helps in the rapid and coordinated communication between neurons. Additionally,
oligodendrocytes provide metabolic support to neurons and contribute to maintaining a stable
microenvironment within the CNS.
Which membrane channel is able to open due to a physical distortion? - ANS ✔✔The
membrane channel that opens due to physical distortion is the mechanically gated channel.
These channels respond to mechanical changes such as stretch, pressure, or vibration and are
crucial in sensory processes like touch and hearing.
Which nerve controls the lifting of the upper eyelid? - ANS ✔✔The nerve responsible for
controlling the lifting of the upper eyelid is the oculomotor nerve (cranial nerve III). It innervates
the levator palpebrae superioris muscle, which is essential for elevating the upper eyelid.
, Which hormones are secreted from the posterior pituitary gland? - ANS ✔✔The posterior
pituitary gland secretes two main hormones: oxytocin and antidiuretic hormone (ADH), also
known as vasopressin.
Oxytocin plays a crucial role in childbirth and lactation, stimulating uterine contractions and milk
ejection.
Antidiuretic hormone (ADH) helps regulate water balance in the body by increasing water
reabsorption in the kidneys.
Which endocrine gland secretes glucagon? - ANS ✔✔Glucagon is secreted by the pancreas.
Specifically, it is produced by the alpha cells in the islets of Langerhans within the pancreas.
Glucagon plays a crucial role in regulating blood sugar levels by promoting the conversion of
stored glycogen in the liver into glucose, which is then released into the bloodstream.
Which glycoprotein hormone is secreted from the anterior pituitary gland? - ANS ✔✔The
anterior pituitary gland secretes several glycoprotein hormones, including:
Luteinizing hormone (LH): Stimulates the secretion of sex hormones by the ovaries and testes.
Follicle-stimulating hormone (FSH): Promotes the growth and maturation of ovarian follicles in
females and spermatogenesis in males.
Thyroid-stimulating hormone (TSH): Stimulates the thyroid gland to produce thyroid hormones.
These hormones play crucial roles in regulating various physiological processes, including
reproduction and metabolism.
The cell's central organelle; contains the cell's DNA - ANS ✔✔Nucleus
The jelly-like substance in which the cell organelles and nucleus are embedded - ANS
✔✔Cytoplasm
A thin and flexible membrane surrounding the cells that acts as a barrier between the
intracellular and the extracellular fluids - ANS ✔✔Cell membrane
questions well answered 2025/2026
What quadrant includes the left lobe of the liver, stomach, pancreas, and portions of the small
and large intestines? - ANS ✔✔Left upper quadrant (LUQ)
Which part of the plasma membrane binds a specific molecule outside the cell? - ANS
✔✔Receptor
A receptor is a type of recognition protein that can selectively bind a specific molecule outside
the cell, and this binding induces a chemical reaction within the cell.
What does it mean if an anatomical structure is caudal? - ANS ✔✔If an anatomical structure is
described as caudal, it means it is located towards the tail or lower part of the body. In humans,
this typically refers to a position closer to the feet or the lower end of the spine.
For example, the legs are caudal to the arms, meaning they are situated lower on the body
compared to the arms.
What is the role of an effector in a negative feedback system? - ANS ✔✔In a negative feedback
system, the effector plays a crucial role in maintaining homeostasis by carrying out the response
to a stimulus. Here's how it works:
Detection: A receptor detects a change in a physiological variable (e.g., temperature, blood
sugar levels).
Signal Processing: The control center (often the brain or endocrine glands) processes this
information and determines the appropriate response.
Action: The effector enacts the response to counteract the initial change and bring the variable
back to its set point.
For example, if your body temperature drops, the effector (such as muscles shivering) generates
heat to raise your body temperature back to normal.
,What is the correct order of the epidermis layer arranged from deep to superficial? - ANS ✔✔1.
Stratum basale (or stratum germinativum)
2. Stratum spinosum
3. Stratum granulosum
4. Stratum lucidum (only present in thick skin, such as the palms and soles)
5. Stratum corneum
Which skin layer contains Langerhans cells? - ANS ✔✔Langerhans cells are primarily found in
the stratum spinosum layer of the epidermis. These cells play a key role in the skin's immune
defense by acting as antigen-presenting cells, which help detect and fight pathogens.
Which degree of burn affects the underlying bones and muscles? - ANS ✔✔Fourth-degree
burns are the most severe and affect not only all layers of the skin but also the underlying
bones, muscles, and tendons. These burns often appear charred or white and are typically
painless because the nerve endings are destroyed.
Which part of the long bone has an epiphyseal line? - ANS ✔✔The epiphyseal line is located at
the junction between the diaphysis (the shaft or central part of the bone) and the epiphysis (the
end part of the bone) in long bones. This line is a remnant of the epiphyseal plate (growth plate)
and indicates that the bone has completed its growth in length.
Which suture is present between the left and right parietal lobes? - ANS ✔✔The suture present
between the left and right parietal lobes is the sagittal suture. This suture runs along the midline
of the skull, connecting the two parietal bones.
Which two bones form the pectoral girdle? - ANS ✔✔The pectoral girdle, also known as the
shoulder girdle, is formed by two bones: the clavicle (collarbone) and the scapula (shoulder
blade). These bones work together to connect the upper limb to the axial skeleton and provide
a wide range of motion for the shoulder and arm.
,What are the periodic invaginations in sarcolemma called? - ANS ✔✔The periodic invaginations
in the sarcolemma are called T-tubules (transverse tubules). These structures play a crucial role
in conducting electrical impulses from the surface of the muscle fiber to its interior, ensuring
that the muscle contracts efficiently and uniformly.
Which medially placed group of muscles is part of the erector spinae? - ANS ✔✔The spinalis
muscles are the most medially placed group within the erector spinae muscle group. These
muscles are located closest to the spine and are responsible for extending and laterally flexing
the cervical and thoracic regions of the spine.
Which thigh muscle is situated below the adductor longus? - ANS ✔✔The muscle situated
below the adductor longus is the adductor magnus. This muscle is a large, triangular muscle
located in the medial compartment of the thigh and plays a significant role in adducting and
medially rotating the thigh
What is the role of oligodendrocytes? - ANS ✔✔Oligodendrocytes play a crucial role in the
central nervous system (CNS) by producing the myelin sheath that insulates axons. This
myelination is essential for the efficient transmission of electrical impulses along nerve fibers,
which helps in the rapid and coordinated communication between neurons. Additionally,
oligodendrocytes provide metabolic support to neurons and contribute to maintaining a stable
microenvironment within the CNS.
Which membrane channel is able to open due to a physical distortion? - ANS ✔✔The
membrane channel that opens due to physical distortion is the mechanically gated channel.
These channels respond to mechanical changes such as stretch, pressure, or vibration and are
crucial in sensory processes like touch and hearing.
Which nerve controls the lifting of the upper eyelid? - ANS ✔✔The nerve responsible for
controlling the lifting of the upper eyelid is the oculomotor nerve (cranial nerve III). It innervates
the levator palpebrae superioris muscle, which is essential for elevating the upper eyelid.
, Which hormones are secreted from the posterior pituitary gland? - ANS ✔✔The posterior
pituitary gland secretes two main hormones: oxytocin and antidiuretic hormone (ADH), also
known as vasopressin.
Oxytocin plays a crucial role in childbirth and lactation, stimulating uterine contractions and milk
ejection.
Antidiuretic hormone (ADH) helps regulate water balance in the body by increasing water
reabsorption in the kidneys.
Which endocrine gland secretes glucagon? - ANS ✔✔Glucagon is secreted by the pancreas.
Specifically, it is produced by the alpha cells in the islets of Langerhans within the pancreas.
Glucagon plays a crucial role in regulating blood sugar levels by promoting the conversion of
stored glycogen in the liver into glucose, which is then released into the bloodstream.
Which glycoprotein hormone is secreted from the anterior pituitary gland? - ANS ✔✔The
anterior pituitary gland secretes several glycoprotein hormones, including:
Luteinizing hormone (LH): Stimulates the secretion of sex hormones by the ovaries and testes.
Follicle-stimulating hormone (FSH): Promotes the growth and maturation of ovarian follicles in
females and spermatogenesis in males.
Thyroid-stimulating hormone (TSH): Stimulates the thyroid gland to produce thyroid hormones.
These hormones play crucial roles in regulating various physiological processes, including
reproduction and metabolism.
The cell's central organelle; contains the cell's DNA - ANS ✔✔Nucleus
The jelly-like substance in which the cell organelles and nucleus are embedded - ANS
✔✔Cytoplasm
A thin and flexible membrane surrounding the cells that acts as a barrier between the
intracellular and the extracellular fluids - ANS ✔✔Cell membrane
