BCS 205-109 Exam 3 questions and
answers graded A+
What does the nervous system do? - correct answer ✔✔1. Controls voluntary movements
2. Seat of consciousness, personality, learning, and memory
3. Regulates many aspects of homeostasis with the endocrine system:
-Respiratory rate
-blood pressure
-body temperature
-sleep/awake cycle
-blood pH
Parts of a neuron - correct answer ✔✔cell body: short, branched processes which sense stimuli
or receive input from other neurons
dendrites: biosynthetic center; manufactures proteins needed for whole neuron
axon hillock: site from which AP may be generated
telodendria: small branches arising from axon
axon terminals: arise from telodendria; contain neurotransmitters; communicate with target
cells
The RMP (resting membrane potential) of a typical neuron is - correct answer ✔✔-70 mV
The RMP (resting membrane potential) is due to unequal distribution of ions on either side of
the plasma membrane. The RMP is created by ________________ and maintained by the
________________. - correct answer ✔✔-Unequal distribution of ions across the plasma
membrane
, -Sodium potassium pump
What ions are present in greater conditions outside the plasma membrane? What ions are
present in greater concentrations inside the plasma membrane? - correct answer ✔✔-Outside:
Sodium and Chloride
-Inside: Potassium and negatively charged proteins
Opening of the sodium channels in the membrane would cause a change in membrane
potential is called _____________. - correct answer ✔✔Depolarization
If the event depicted in question #1 (depolarization) was immediately followed by opening of
potassium gated channels, the plasma membrane would experience __________. - correct
answer ✔✔Repolarization
If no event occurred prior, and potassium and chloride gated channels opened, the plasma
membrane would _________. - correct answer ✔✔Hyper polarize
True or False: "Graded" means that the number of gated channels which open during a local
potential varies based upon the strength of the stimulus. - correct answer ✔✔True
True or False: The strength of a local potential remains constant as it heads toward the axon
hillock. - correct answer ✔✔False: Local potentials are only good for local signaling not for long
distance signaling
What criteria must be met for an action potential to be generated? - correct answer ✔✔1. Local
potential must depolarize the axon hillock to a value called the threshold (-55 to -60 millivolts)
During the action potential; what two events occur at the peak? - correct answer ✔✔Voltage
gated sodium channels close and voltage gated sodium channels open
answers graded A+
What does the nervous system do? - correct answer ✔✔1. Controls voluntary movements
2. Seat of consciousness, personality, learning, and memory
3. Regulates many aspects of homeostasis with the endocrine system:
-Respiratory rate
-blood pressure
-body temperature
-sleep/awake cycle
-blood pH
Parts of a neuron - correct answer ✔✔cell body: short, branched processes which sense stimuli
or receive input from other neurons
dendrites: biosynthetic center; manufactures proteins needed for whole neuron
axon hillock: site from which AP may be generated
telodendria: small branches arising from axon
axon terminals: arise from telodendria; contain neurotransmitters; communicate with target
cells
The RMP (resting membrane potential) of a typical neuron is - correct answer ✔✔-70 mV
The RMP (resting membrane potential) is due to unequal distribution of ions on either side of
the plasma membrane. The RMP is created by ________________ and maintained by the
________________. - correct answer ✔✔-Unequal distribution of ions across the plasma
membrane
, -Sodium potassium pump
What ions are present in greater conditions outside the plasma membrane? What ions are
present in greater concentrations inside the plasma membrane? - correct answer ✔✔-Outside:
Sodium and Chloride
-Inside: Potassium and negatively charged proteins
Opening of the sodium channels in the membrane would cause a change in membrane
potential is called _____________. - correct answer ✔✔Depolarization
If the event depicted in question #1 (depolarization) was immediately followed by opening of
potassium gated channels, the plasma membrane would experience __________. - correct
answer ✔✔Repolarization
If no event occurred prior, and potassium and chloride gated channels opened, the plasma
membrane would _________. - correct answer ✔✔Hyper polarize
True or False: "Graded" means that the number of gated channels which open during a local
potential varies based upon the strength of the stimulus. - correct answer ✔✔True
True or False: The strength of a local potential remains constant as it heads toward the axon
hillock. - correct answer ✔✔False: Local potentials are only good for local signaling not for long
distance signaling
What criteria must be met for an action potential to be generated? - correct answer ✔✔1. Local
potential must depolarize the axon hillock to a value called the threshold (-55 to -60 millivolts)
During the action potential; what two events occur at the peak? - correct answer ✔✔Voltage
gated sodium channels close and voltage gated sodium channels open
