BIOB34 Final Exam Questions with Correct Answers Graded A+
Outside vertebrates, the animal with the highest brain:body ratio is... - Answers ... octopi
Lack Neurons: - Answers No nervous system (songes and placozoas)
Nerve Net: - Answers Uniformly distributed neurons (Cnidarians, jellyfish)
Centralized Nervous System: - Answers Centralized in one spot, usually head. Usually bilateral body
symmetry (Chordates, spiders, insects, and molluscs)
Nervous system is not independent of influence as seen in... - Answers ... migratory bats which lose mass
from neocortex to reduce weight
Sponges can signal porocytes to turn off without neurons by using... - Answers ... syncytium, a single
multinucleate sheet
Reflex Only Principle: - Answers Neuronal detection causes instant and unconscious movement
Cephalization: - Answers Develop brain in head (anterior) of animal
Dendrites: - Answers Collect electrical signals
Cell Body (Soma): - Answers Integrates input and generates output to axon
Axon: - Answers Conducts electric signal to presynaptic terminal
Presynaptic Terminal: - Answers Transmits signal to next cell
All cells have an electric potential, but neurons... - Answers ... change theirs
ECF is rich in... - Answers ... Na and Cl
ICF is rich in... - Answers ... K
If ions were able to freely move across membrane... - Answers ... there'd be no membrane potential
Equilibrium Potential: - Answers When concentration gradient force and electrical force balance out
Nernst Equation: - Answers Calculates permeability for a single ion with different concentrations
Goldman Equation: - Answers Calculates permeability for set of ion with different concentrations and
permeabilities to the membrane
The membrane potential of a neuron is... - Answers ... -66.2 mV
, Major contributors in how fast signal transmits within a neuron are... - Answers ... 1. Cytosolic resistance
to current flow
2. Membrane not perfectly resistant
At resting state of membrane... - Answers ... Na channel (M Gate) is closed, K channel is closed. No net
movement
At depolarization state of membrane... - Answers ... Na channel is open, K channel is closed. Na rushes
into cell
At repolarization state of membrane... - Answers ... Na channel (H Gate) is closed, K channel is open. K
moves out
At undershoot state of membrane... - Answers ... Na channel (M and H Gate) is closed. K channel is
open. K moves out of cell
M Gate: - Answers Outer Na Gate. Voltage dependent
H Gate: - Answers Inner Na Gate. Time dependent
Closure of H Gate prevents... - Answers ... backwards propagation
Length Constant: - Answers Distance where graded potential is 37% of original value
Rm: - Answers Resistance of membrane
Ri: - Answers Internal neuron resistance
To make an action potential travel faster... - Answers ... increase Rm or decrease Ri
In giant squid nerve... - Answers ... cluster of small axons surround a giant axon
In increasing or decreasing axon diameter... - Answers ... surface area doesn't change as fast as volume
Nodes of Ranvier: - Answers Gaps in the myelin sheath where action potentials take place
In electrical synapses... - Answers ... ions flow directly into other neurons. Flow can be bidirectional
At axon terminals, there are no longer Na channels, but... - Answers ... Ca channels which open at
depolarization
Ca induces vesicle release by... - Answers ... turning on Protein Kinase A which phosphorylates synapsin
that is tethering vesicle to cytoskeleton (actin)
Criteria for neurotransmitter: - Answers 1. Synthesized by neuron
2. Released from presynaptic terminal following depolarization
Outside vertebrates, the animal with the highest brain:body ratio is... - Answers ... octopi
Lack Neurons: - Answers No nervous system (songes and placozoas)
Nerve Net: - Answers Uniformly distributed neurons (Cnidarians, jellyfish)
Centralized Nervous System: - Answers Centralized in one spot, usually head. Usually bilateral body
symmetry (Chordates, spiders, insects, and molluscs)
Nervous system is not independent of influence as seen in... - Answers ... migratory bats which lose mass
from neocortex to reduce weight
Sponges can signal porocytes to turn off without neurons by using... - Answers ... syncytium, a single
multinucleate sheet
Reflex Only Principle: - Answers Neuronal detection causes instant and unconscious movement
Cephalization: - Answers Develop brain in head (anterior) of animal
Dendrites: - Answers Collect electrical signals
Cell Body (Soma): - Answers Integrates input and generates output to axon
Axon: - Answers Conducts electric signal to presynaptic terminal
Presynaptic Terminal: - Answers Transmits signal to next cell
All cells have an electric potential, but neurons... - Answers ... change theirs
ECF is rich in... - Answers ... Na and Cl
ICF is rich in... - Answers ... K
If ions were able to freely move across membrane... - Answers ... there'd be no membrane potential
Equilibrium Potential: - Answers When concentration gradient force and electrical force balance out
Nernst Equation: - Answers Calculates permeability for a single ion with different concentrations
Goldman Equation: - Answers Calculates permeability for set of ion with different concentrations and
permeabilities to the membrane
The membrane potential of a neuron is... - Answers ... -66.2 mV
, Major contributors in how fast signal transmits within a neuron are... - Answers ... 1. Cytosolic resistance
to current flow
2. Membrane not perfectly resistant
At resting state of membrane... - Answers ... Na channel (M Gate) is closed, K channel is closed. No net
movement
At depolarization state of membrane... - Answers ... Na channel is open, K channel is closed. Na rushes
into cell
At repolarization state of membrane... - Answers ... Na channel (H Gate) is closed, K channel is open. K
moves out
At undershoot state of membrane... - Answers ... Na channel (M and H Gate) is closed. K channel is
open. K moves out of cell
M Gate: - Answers Outer Na Gate. Voltage dependent
H Gate: - Answers Inner Na Gate. Time dependent
Closure of H Gate prevents... - Answers ... backwards propagation
Length Constant: - Answers Distance where graded potential is 37% of original value
Rm: - Answers Resistance of membrane
Ri: - Answers Internal neuron resistance
To make an action potential travel faster... - Answers ... increase Rm or decrease Ri
In giant squid nerve... - Answers ... cluster of small axons surround a giant axon
In increasing or decreasing axon diameter... - Answers ... surface area doesn't change as fast as volume
Nodes of Ranvier: - Answers Gaps in the myelin sheath where action potentials take place
In electrical synapses... - Answers ... ions flow directly into other neurons. Flow can be bidirectional
At axon terminals, there are no longer Na channels, but... - Answers ... Ca channels which open at
depolarization
Ca induces vesicle release by... - Answers ... turning on Protein Kinase A which phosphorylates synapsin
that is tethering vesicle to cytoskeleton (actin)
Criteria for neurotransmitter: - Answers 1. Synthesized by neuron
2. Released from presynaptic terminal following depolarization
