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BIOD 331 PATHOPHYSIOLOGY ALL MODULES 2025/2026 –
COMPLETE QUESTIONS & ANSWERS BANK | ACTUAL EXAM
WITH FREQUENTLY TESTED QUESTIONS + STUDY GUIDE |
EXPERT VERIFIED || AWARDED A+||
Cell signaling - ANSWER-All multicellular organisms rely on a tightly
regulated system of transmitting information between cells
Endocrine signaling - ANSWER-Depends on hormones carried in the
bloodstream to act on cells throughout the body.
Paracrine signaling - ANSWER-Occurs when enzymes metabolize
chemical mediators, producing a change in neighboring cells.
Autocrine signaling - ANSWER-Occurs when a cell releases a chemical
into the extracellular fluid that affects its own activity.
Synaptic signaling - ANSWER-Is a specialized system that occurs in the
nervous system as neurotransmitters act on adjacent nerve cells through
synapses, which are small gaps or junctions between the nerve cells.
Receptor activation - ANSWER-The signal generates a cascade of events
leading to a physiological response. Receptors can be activated by
neurotransmitters, steroids, protein hormones, etc
G-protein-linked receptors - ANSWER-The largest in number. They have a
ligand-binding extracellular receptor component. G proteins function as an
on-off switch to convert first messengers into second messengers. When
the receptor is activated, the protein complex has a high affinity for GTP
(guanine triphosphate). When the receptor is inactivated, it binds GDP
(guanine diphosphate). In short, it serves as the on-off switch for signal
transduction, or cell signaling.
Enzyme-linked receptors - ANSWER-Have ligand-binding site on the
outside of the cell membrane. Receptor binding activates an associated
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intracellular domain with enzyme activity. Enzyme-linked receptors are also
involved in the function of growth factors. Many growth factors are
important messengers that signal for cell growth and/or replacement.
These growth factors bind to specific receptors that deliver signals to target
cells.
Ion-channel-linked receptors - ANSWER-Found in nerve cells and muscle
cells. Considered "excitable cells", and the synaptic signaling that occurs is
rapid. Neurotransmitters use this to open or close ion channels formed by
proteins in the cell membrane.
Intracellular receptors - ANSWER-In the cytoplasmic side of the
membrane. Not exposed to the extracellular environment, intracellular
receptors are often activated by hormones. For example, both thyroid and
steroid hormones move directly across the membrane bilayer (bypassing
surface receptors) and bind to its specific receptor located in the cytoplasm.
Once bound, this receptor-hormone complex is trafficked toward the
nucleus where it binds to DNA, leading to an increase in the transcription of
mRNA.
Cell membrane - ANSWER-Acts as a barrier, controlling what substances
can enter and leave the cell. Movement through the cell can occur
passively (without using energy), or actively (using energy).
Diffusion - ANSWER-Process by which molecules move from an area of
higher concentration to an area of lower concentration. This flow of
molecules continues until they are equally distributed on both sides of the
membrane. Occurs easily with lipid-soluble molecules like oxygen, alcohol,
carbon dioxide, and fatty acids. Diffusion rates increase in direct proportion
to increased temperatures.
Osmosis - ANSWER-Movement of water from an area of low solute (few
substances dissolved in water) to an area of high solute (many particles in
the water). Moves through channels called aquaporins.
Osmotic pressure - ANSWER-The pressure that water generates as it
moves through the membrane
Facilitated diffusion - ANSWER-Uses a transport protein to help lipid
insoluble or large molecules pass through the membrane.
BIOD 331 PATHOPHYSIOLOGY ALL MODULES 2025/2026 –
COMPLETE QUESTIONS & ANSWERS BANK | ACTUAL EXAM
WITH FREQUENTLY TESTED QUESTIONS + STUDY GUIDE |
EXPERT VERIFIED || AWARDED A+||
Cell signaling - ANSWER-All multicellular organisms rely on a tightly
regulated system of transmitting information between cells
Endocrine signaling - ANSWER-Depends on hormones carried in the
bloodstream to act on cells throughout the body.
Paracrine signaling - ANSWER-Occurs when enzymes metabolize
chemical mediators, producing a change in neighboring cells.
Autocrine signaling - ANSWER-Occurs when a cell releases a chemical
into the extracellular fluid that affects its own activity.
Synaptic signaling - ANSWER-Is a specialized system that occurs in the
nervous system as neurotransmitters act on adjacent nerve cells through
synapses, which are small gaps or junctions between the nerve cells.
Receptor activation - ANSWER-The signal generates a cascade of events
leading to a physiological response. Receptors can be activated by
neurotransmitters, steroids, protein hormones, etc
G-protein-linked receptors - ANSWER-The largest in number. They have a
ligand-binding extracellular receptor component. G proteins function as an
on-off switch to convert first messengers into second messengers. When
the receptor is activated, the protein complex has a high affinity for GTP
(guanine triphosphate). When the receptor is inactivated, it binds GDP
(guanine diphosphate). In short, it serves as the on-off switch for signal
transduction, or cell signaling.
Enzyme-linked receptors - ANSWER-Have ligand-binding site on the
outside of the cell membrane. Receptor binding activates an associated
, 2|Page
intracellular domain with enzyme activity. Enzyme-linked receptors are also
involved in the function of growth factors. Many growth factors are
important messengers that signal for cell growth and/or replacement.
These growth factors bind to specific receptors that deliver signals to target
cells.
Ion-channel-linked receptors - ANSWER-Found in nerve cells and muscle
cells. Considered "excitable cells", and the synaptic signaling that occurs is
rapid. Neurotransmitters use this to open or close ion channels formed by
proteins in the cell membrane.
Intracellular receptors - ANSWER-In the cytoplasmic side of the
membrane. Not exposed to the extracellular environment, intracellular
receptors are often activated by hormones. For example, both thyroid and
steroid hormones move directly across the membrane bilayer (bypassing
surface receptors) and bind to its specific receptor located in the cytoplasm.
Once bound, this receptor-hormone complex is trafficked toward the
nucleus where it binds to DNA, leading to an increase in the transcription of
mRNA.
Cell membrane - ANSWER-Acts as a barrier, controlling what substances
can enter and leave the cell. Movement through the cell can occur
passively (without using energy), or actively (using energy).
Diffusion - ANSWER-Process by which molecules move from an area of
higher concentration to an area of lower concentration. This flow of
molecules continues until they are equally distributed on both sides of the
membrane. Occurs easily with lipid-soluble molecules like oxygen, alcohol,
carbon dioxide, and fatty acids. Diffusion rates increase in direct proportion
to increased temperatures.
Osmosis - ANSWER-Movement of water from an area of low solute (few
substances dissolved in water) to an area of high solute (many particles in
the water). Moves through channels called aquaporins.
Osmotic pressure - ANSWER-The pressure that water generates as it
moves through the membrane
Facilitated diffusion - ANSWER-Uses a transport protein to help lipid
insoluble or large molecules pass through the membrane.
