BIOL 373 CERTIFICATION EVALUATION
TESTED QUESTIONS WITH COMPLETE
SOLUTION PACKAGE
●● What is the difference between process and function?
Answer: - process = "how"
- function = "why"
●● What is homeostasis with respect to a fluid?
Answer: Maintenance of a relatively stable internal cellular fluid
●● Who coined the term "homeostasis?"
Answer: Walter Cannon
●● What is pathophysiology?
Answer: The study of when systems fail to compensate
●● What is local control? Reflex control? What modulates reflex
control?
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
Answer: - osmolarity
-T
- BP
●● What are the three types of feedback mechanisms? Which is most
common? least common?
Answer: Negative, positive and feedforward. Negative feedback
→negative very common
→positive very rare
●● What is responsible for most communication - electrical or chemical
signals?
Answer: Chemical
●● Define target cells WRT sent signals.
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?
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?
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.
Answer: - ion channel
- enzyme-coupled receptor
- GPCR
●● What are the main types of second messengers? Name a
representative member of each.
Answer: - nucleotides; cAMP
- lipid-derived molecules; IP_3
- ions; Ca²⁺
●● How can one signal have different effects on different cell types?
Answer: One ligand may have several different types of receptors
●● What aspects of kinetics and thermodynamics affect ligand-receptor
interactions?
Answer: K_eq (rel. affinity), saturation
, ●● How can cells change their response to signals?
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?
Answer: α constrict, reducing blood flow; β₂ dilate, increasing blood
flow
●● Explain the difference between an agonist and an antagonist.
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?
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?
TESTED QUESTIONS WITH COMPLETE
SOLUTION PACKAGE
●● What is the difference between process and function?
Answer: - process = "how"
- function = "why"
●● What is homeostasis with respect to a fluid?
Answer: Maintenance of a relatively stable internal cellular fluid
●● Who coined the term "homeostasis?"
Answer: Walter Cannon
●● What is pathophysiology?
Answer: The study of when systems fail to compensate
●● What is local control? Reflex control? What modulates reflex
control?
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
Answer: - osmolarity
-T
- BP
●● What are the three types of feedback mechanisms? Which is most
common? least common?
Answer: Negative, positive and feedforward. Negative feedback
→negative very common
→positive very rare
●● What is responsible for most communication - electrical or chemical
signals?
Answer: Chemical
●● Define target cells WRT sent signals.
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?
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?
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.
Answer: - ion channel
- enzyme-coupled receptor
- GPCR
●● What are the main types of second messengers? Name a
representative member of each.
Answer: - nucleotides; cAMP
- lipid-derived molecules; IP_3
- ions; Ca²⁺
●● How can one signal have different effects on different cell types?
Answer: One ligand may have several different types of receptors
●● What aspects of kinetics and thermodynamics affect ligand-receptor
interactions?
Answer: K_eq (rel. affinity), saturation
, ●● How can cells change their response to signals?
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?
Answer: α constrict, reducing blood flow; β₂ dilate, increasing blood
flow
●● Explain the difference between an agonist and an antagonist.
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?
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?
