Biology 3 Exam 4 questions and
answers graded A+
Which of the following was a benefit of evolving neurons? - correct answer ✔✔ - Neurons
enabled animals to coordinate sensing, movement, and eating.
- Neurons enable organisms to send signals long distances across large bodies.
Dendrite - correct answer ✔✔ Input arm of neurons which has graded potentials
Axon - correct answer ✔✔ Output arm of neuron which has action potential
Synapse - correct answer ✔✔ Gap between adjacent neurons
Neurotransmitter - correct answer ✔✔ Chemical signal which diffuses across gap between
neurons
Ion pump - correct answer ✔✔ Set up concentration gradient
Leak Channel - correct answer ✔✔ Set resting membrane potential
Voltage Gated Sodium Channel - correct answer ✔✔ Enable positive extent of action potential
Voltage Gated Calcium Channel - correct answer ✔✔ Enable neurotransmitter release
, Which of the following scenarios would lead to a negative membrane potential? Assume for
each case that the appropriate leaky channel is present in the cell's membrane. - correct answer
✔✔ -K+ concentration inside cell> outside cell
- Cl+ concentration outside cell> inside
At mammalian body temperature, the Goldman equation is given by______ if there is no
membrane permeability for sodium permeability for sodium or chlorine, what does this
equation reduce to? - correct answer ✔✔ The nerst equation for K
If voltage gated chlorine channels open, what happens to the membrane potential? - correct
answer ✔✔ It becomes more negative, hyperpolarizing
What causes the membrane potential to start to shift from the resting membrane potential
before the acton potential is triggered? - correct answer ✔✔ Ion channels open in the dendrites
in response to stimulus
Dendrites - correct answer ✔✔ non-voltage gated Na+ channels
Axons - correct answer ✔✔ Voltage gated Na+ channels
Synapse - correct answer ✔✔ Voltage gated Na+ channels
What is moving down the axon during an action potential? - correct answer ✔✔ A wave of
depolarization
Why does the action potential only go in one direction? - correct answer ✔✔ The voltage gated
sodium channels become inactivated
answers graded A+
Which of the following was a benefit of evolving neurons? - correct answer ✔✔ - Neurons
enabled animals to coordinate sensing, movement, and eating.
- Neurons enable organisms to send signals long distances across large bodies.
Dendrite - correct answer ✔✔ Input arm of neurons which has graded potentials
Axon - correct answer ✔✔ Output arm of neuron which has action potential
Synapse - correct answer ✔✔ Gap between adjacent neurons
Neurotransmitter - correct answer ✔✔ Chemical signal which diffuses across gap between
neurons
Ion pump - correct answer ✔✔ Set up concentration gradient
Leak Channel - correct answer ✔✔ Set resting membrane potential
Voltage Gated Sodium Channel - correct answer ✔✔ Enable positive extent of action potential
Voltage Gated Calcium Channel - correct answer ✔✔ Enable neurotransmitter release
, Which of the following scenarios would lead to a negative membrane potential? Assume for
each case that the appropriate leaky channel is present in the cell's membrane. - correct answer
✔✔ -K+ concentration inside cell> outside cell
- Cl+ concentration outside cell> inside
At mammalian body temperature, the Goldman equation is given by______ if there is no
membrane permeability for sodium permeability for sodium or chlorine, what does this
equation reduce to? - correct answer ✔✔ The nerst equation for K
If voltage gated chlorine channels open, what happens to the membrane potential? - correct
answer ✔✔ It becomes more negative, hyperpolarizing
What causes the membrane potential to start to shift from the resting membrane potential
before the acton potential is triggered? - correct answer ✔✔ Ion channels open in the dendrites
in response to stimulus
Dendrites - correct answer ✔✔ non-voltage gated Na+ channels
Axons - correct answer ✔✔ Voltage gated Na+ channels
Synapse - correct answer ✔✔ Voltage gated Na+ channels
What is moving down the axon during an action potential? - correct answer ✔✔ A wave of
depolarization
Why does the action potential only go in one direction? - correct answer ✔✔ The voltage gated
sodium channels become inactivated
