BIOL 373 EXAM QUESTIONS WITH COMPLETE
SOLUTIONS
What is physiology? - CORRECT ANSWER✔✔-The science of the function of living
| | | | | | | | | | | |
system
What is the difference between process and function? - CORRECT ANSWER✔✔--
| | | | | | | | | | |
process = "how" | |
- function = "why"
| | |
What is homeostasis with respect to a fluid? - CORRECT ANSWER✔✔-
| | | | | | | | | |
Maintenance of a relatively stable internal cellular fluid
| | | | | | |
Who coined the term "homeostasis?" - CORRECT ANSWER✔✔-Walter Cannon
| | | | | | | |
What is pathophysiology? - CORRECT ANSWER✔✔-The study of when systems fail
| | | | | | | | | |
to compensate
| |
What is local control? Reflex control? What modulates reflex control? - CORRECT
| | | | | | | | | | | |
ANSWER✔✔-- local control = changes near the site of damage
| | | | | | | | |
- reflex control = over long distances; managed by the CNS
| | | | | | | | | |
List some examples of variables monitored by the CNS - CORRECT ANSWER✔✔--
| | | | | | | | | | | |
osmolarity
,-T |
- BP|
What are the three types of feedback mechanisms? Which is most common?
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least common? - CORRECT ANSWER✔✔-Negative, positive and feedforward.
| | | | | | | |
Negative feedback →negative very common
| | | |
→positive very rare | |
What is responsible for most communication - electrical or chemical signals? -
| | | | | | | | | | | |
CORRECT ANSWER✔✔-Chemical |
Define target cells WRT sent signals. - CORRECT ANSWER✔✔-Target cells are
| | | | | | | | | | |
those cells which are able to respond to chemical signals, and contain a receptor
| | | | | | | | | | | | | |
for it. |
What are forms of long-range cell-cell communication? - CORRECT ANSWER✔✔-
| | | | | | | | |
endocrine (chemical hormone), neural and neuro endocrine (chemicals at axon
| | | | | | | | | |
terminal secrete into the bloodstream).
| | | |
Where are ligand receptors located? What do these specific locations yield in
| | | | | | | | | | | |
terms of function? - CORRECT ANSWER✔✔-A *protein* which projects outside of
| | | | | | | | | |
|the membrane or are within the membrane; hydrophobic ligands will diffuse into
| | | | | | | | | | |
|the cytoplasm; hydrophilic via an intracellular receptor (consider the lipo and
| | | | | | | | | | |
hydrophobicity WRT location) | |
name the three main types of membrane receptors covered in 373. - CORRECT
| | | | | | | | | | | | |
ANSWER✔✔-- ion channel | |
,- enzyme-coupled receptor
| |
- GPCR
|
What are the main types of second messengers? Name a representative member
| | | | | | | | | | | |
of each. - CORRECT ANSWER✔✔-- nucleotides; cAMP
| | | | | |
- lipid-derived molecules; IP_3
| | |
- ions; Ca²⁺
| |
How can one signal have different effects on different cell types? - CORRECT
| | | | | | | | | | | | |
ANSWER✔✔-One ligand may have several different types of receptors | | | | | | | |
What aspects of kinetics and thermodynamics affect ligand-receptor interactions?
| | | | | | | |
- CORRECT ANSWER✔✔-K_eq (rel. affinity), saturation
| | | | | |
How can cells change their response to signals? - CORRECT ANSWER✔✔-- ↑
| | | | | | | | | | | |
n_receptors by changing receptor number or sensitivity
| | | | | |
- ↓ n_receptors by internalizing the surface protein
| | | | | | |
*- Δsensitivity by ℗*
| | |
What are the effects of Epi on α receptors? β₂ receptors? - CORRECT
| | | | | | | | | | | | |
ANSWER✔✔-α constrict, reducing blood flow; β₂ dilate, increasing blood flow
| | | | | | | | |
Explain the difference between an agonist and an antagonist. - CORRECT
| | | | | | | | | | |
ANSWER✔✔-Agonists exhibit the same response as the ligand, whereas | | | | | | | | |
antagonists occupy but do not activate the receptor
| | | | | | |
, Explain the pathogenesis of cholera. What effect does it have on the molecules? -
| | | | | | | | | | | | |
CORRECT ANSWER✔✔-- comes from contaminates *water*
| | | | | |
- produce a toxin which affects the small intestine, yielding water loss
| | | | | | | | | | |
- disables intrinsic GTPase activity of α subunit
| | | | | | |
Explain the activity of GPCRs. What NXP does it have when "off?" When on? How
| | | | | | | | | | | | | | |
does it inactivate? What subunits are considered active? - CORRECT
| | | | | | | | | |
ANSWER✔✔-- consists of a receptor portion, and then an α and βɣ subunits; the
| | | | | | | | | | | | | |
βɣ seperate from the α.
| | | | |
- GDP when off
| | |
- GTP when on
| | |
- inactivates by hydrolysis of the terminal ℗
| | | | | | |
- βɣ yield activation
| | |
Which subinit does the GTP attach to? Which has GTPase activity? Does the GPCR
| | | | | | | | | | | | |
attach another ℗, or does it swap GDP to GTP for activation? - CORRECT
| | | | | | | | | | | | | | |
ANSWER✔✔-- GTP on α | | |
- α has GTPase activity
| | | |
- GDP is exchanged for GTP for activation
| | | | | | |
What is the time span for Gα GTP hydrolysis? What disease is implicated in failure
| | | | | | | | | | | | | |
of hydrolysis? - CORRECT ANSWER✔✔-Usually seconds; collera
| | | | | | |
Explain tonic control. Is it under parasympathetic control? - CORRECT
| | | | | | | | | |
ANSWER✔✔-Δn_signals yielding a ∇ of signals | | | | |
SOLUTIONS
What is physiology? - CORRECT ANSWER✔✔-The science of the function of living
| | | | | | | | | | | |
system
What is the difference between process and function? - CORRECT ANSWER✔✔--
| | | | | | | | | | |
process = "how" | |
- function = "why"
| | |
What is homeostasis with respect to a fluid? - CORRECT ANSWER✔✔-
| | | | | | | | | |
Maintenance of a relatively stable internal cellular fluid
| | | | | | |
Who coined the term "homeostasis?" - CORRECT ANSWER✔✔-Walter Cannon
| | | | | | | |
What is pathophysiology? - CORRECT ANSWER✔✔-The study of when systems fail
| | | | | | | | | |
to compensate
| |
What is local control? Reflex control? What modulates reflex control? - CORRECT
| | | | | | | | | | | |
ANSWER✔✔-- local control = changes near the site of damage
| | | | | | | | |
- reflex control = over long distances; managed by the CNS
| | | | | | | | | |
List some examples of variables monitored by the CNS - CORRECT ANSWER✔✔--
| | | | | | | | | | | |
osmolarity
,-T |
- BP|
What are the three types of feedback mechanisms? Which is most common?
| | | | | | | | | | | |
least common? - CORRECT ANSWER✔✔-Negative, positive and feedforward.
| | | | | | | |
Negative feedback →negative very common
| | | |
→positive very rare | |
What is responsible for most communication - electrical or chemical signals? -
| | | | | | | | | | | |
CORRECT ANSWER✔✔-Chemical |
Define target cells WRT sent signals. - CORRECT ANSWER✔✔-Target cells are
| | | | | | | | | | |
those cells which are able to respond to chemical signals, and contain a receptor
| | | | | | | | | | | | | |
for it. |
What are forms of long-range cell-cell communication? - CORRECT ANSWER✔✔-
| | | | | | | | |
endocrine (chemical hormone), neural and neuro endocrine (chemicals at axon
| | | | | | | | | |
terminal secrete into the bloodstream).
| | | |
Where are ligand receptors located? What do these specific locations yield in
| | | | | | | | | | | |
terms of function? - CORRECT ANSWER✔✔-A *protein* which projects outside of
| | | | | | | | | |
|the membrane or are within the membrane; hydrophobic ligands will diffuse into
| | | | | | | | | | |
|the cytoplasm; hydrophilic via an intracellular receptor (consider the lipo and
| | | | | | | | | | |
hydrophobicity WRT location) | |
name the three main types of membrane receptors covered in 373. - CORRECT
| | | | | | | | | | | | |
ANSWER✔✔-- ion channel | |
,- enzyme-coupled receptor
| |
- GPCR
|
What are the main types of second messengers? Name a representative member
| | | | | | | | | | | |
of each. - CORRECT ANSWER✔✔-- nucleotides; cAMP
| | | | | |
- lipid-derived molecules; IP_3
| | |
- ions; Ca²⁺
| |
How can one signal have different effects on different cell types? - CORRECT
| | | | | | | | | | | | |
ANSWER✔✔-One ligand may have several different types of receptors | | | | | | | |
What aspects of kinetics and thermodynamics affect ligand-receptor interactions?
| | | | | | | |
- CORRECT ANSWER✔✔-K_eq (rel. affinity), saturation
| | | | | |
How can cells change their response to signals? - CORRECT ANSWER✔✔-- ↑
| | | | | | | | | | | |
n_receptors by changing receptor number or sensitivity
| | | | | |
- ↓ n_receptors by internalizing the surface protein
| | | | | | |
*- Δsensitivity by ℗*
| | |
What are the effects of Epi on α receptors? β₂ receptors? - CORRECT
| | | | | | | | | | | | |
ANSWER✔✔-α constrict, reducing blood flow; β₂ dilate, increasing blood flow
| | | | | | | | |
Explain the difference between an agonist and an antagonist. - CORRECT
| | | | | | | | | | |
ANSWER✔✔-Agonists exhibit the same response as the ligand, whereas | | | | | | | | |
antagonists occupy but do not activate the receptor
| | | | | | |
, Explain the pathogenesis of cholera. What effect does it have on the molecules? -
| | | | | | | | | | | | |
CORRECT ANSWER✔✔-- comes from contaminates *water*
| | | | | |
- produce a toxin which affects the small intestine, yielding water loss
| | | | | | | | | | |
- disables intrinsic GTPase activity of α subunit
| | | | | | |
Explain the activity of GPCRs. What NXP does it have when "off?" When on? How
| | | | | | | | | | | | | | |
does it inactivate? What subunits are considered active? - CORRECT
| | | | | | | | | |
ANSWER✔✔-- consists of a receptor portion, and then an α and βɣ subunits; the
| | | | | | | | | | | | | |
βɣ seperate from the α.
| | | | |
- GDP when off
| | |
- GTP when on
| | |
- inactivates by hydrolysis of the terminal ℗
| | | | | | |
- βɣ yield activation
| | |
Which subinit does the GTP attach to? Which has GTPase activity? Does the GPCR
| | | | | | | | | | | | |
attach another ℗, or does it swap GDP to GTP for activation? - CORRECT
| | | | | | | | | | | | | | |
ANSWER✔✔-- GTP on α | | |
- α has GTPase activity
| | | |
- GDP is exchanged for GTP for activation
| | | | | | |
What is the time span for Gα GTP hydrolysis? What disease is implicated in failure
| | | | | | | | | | | | | |
of hydrolysis? - CORRECT ANSWER✔✔-Usually seconds; collera
| | | | | | |
Explain tonic control. Is it under parasympathetic control? - CORRECT
| | | | | | | | | |
ANSWER✔✔-Δn_signals yielding a ∇ of signals | | | | |
