Biology 252 Exam 1
______ and _______ induce the formation of the BBB. - ANSAstrocytes and Pericytes
______ gated channels generate local, graded potentials. - ANSChemically gated channels
generate local potentials.
________ channels are found mainly on the axon and axon hillock (trigger zone). -
ANSVoltage gated channels
1st type of information provided by sensation receptors: modality - ANSType of stimulus or
the sensation it produces
-temp vs touch
-vibration vs sound
- by looking at your laptop you cannot tell how it tastes but you can see it.
2nd type of information: location - ANSEncoded by which nerve fibers are issuing signals to
the brain. Receptive fields tell the area covered by one single receptor.
3rd type of information: Intensity - ANSHow strong the stimulus is
A) as stimulus intensity rises, the firing frequencies of sensory nerve fibers rise (b) intense
stimuli recruit greater numbers of nerve fibers to fire; and (c) weak stimuli activate only the
most sensitive nerve fibers, whereas strong stimuli can activate a less sensitive group of
fibers with higher thresholds. Thus, the brain can distinguish intensities based on which
fibers are firing, how many are doing so, and how fast they are firing.
Duration - ANSPhasic receptors are the fourth kind of information: you're getting used to the
shirt you're wearing because they adapt quickly. - Notify on us change (onset and cessation
of the stimulus)
Tonic receptors are slow adapting receptors (e.g. pain does not go away)
- Notify on duration of the stimulus
A child eats a whole bottle of salt (NaCl) tablets. What effect does this have on the resting
membrane potential? - ANSAlthough there are leakage channels, the sodium permeability is
so low the change will be minor. Think about a lot of students outside a small door that
wants to get in, but they cannot all get through at once.
Absolute Refractory Period - ANSNa+ channels have not yet reset to the resting positions.
A new AP CANNOT be generated. (before the peak)
Action potentials can only be generated and propagated in ______ and _______. -
ANSNeurons (only at the axon) and muscles. Why?
Antagonistic control - ANSMost internal organs are innervated by both divisions of the ANS,
which exhibit antagonistic control
Ex; heart rate. increase in sympathetic stimulation causes HR to increase, parasympathetic
causes it to decrease
Astrocytes - ANS- support and brace neurons
- control the chemical environment
- cover the brain and nonsynaptic regions of neurons
- supportive framework of CNS
- induce BBB
- influence synaptic signaling
- secrete growth factors
, - removes K+ and some NTs from ECF of brain and spinal cord
- form scar tissue
At what point does an action potential become an all or none process? - ANSUpon reaching
the threshold
Auditory association area - ANSStores memories of sounds and permits perception of
sounds
Autonomic Nervous System - ANSConsists of motor neurons that:
- Make adjustments to ensure optimal support for body activities
- Operate via subconscious control
Bottom - visual cortex (blindness) - ANSallows you to see general shapes and shadows but
no identification
Broca's area - ANScontrols muscles involved in speech. Sends messages to the primary
motor cortex and this PMC tells muscles to contract, etc.
Present in one hemisphere.
Chemically (ligand) gated channels - ANSa ligand binds to receptor causing a
conformational change and opening the gate to the ions.
- can be specific or not specific (Ach at neural muscular junctions is permeable to all cations
- noth Na and K).
Chemoreceptors - ANSrespond to chemicals, including odors, tastes, and body fluid
composition.
Depolarize - ANSMaking the cell less polarized (closer to zero).
Describe the soma, neurofibrils, Nissl bodies, dendrites, axon and axon hillock. - ANSSoma-
body of the neuron cell.
Neurofibrils- work with microtubules to compartmentalize rough ER into Nissl bodies.
Nissl bodies- help identify neurons in tissue sections with mixed cell types
Dendrites- primary site for receiving signals from other neurons
axon hillock- nerve fiber where axon originates
axon- conducs nerve signals to remote point from the soma. contains Varicosities secrete
NTs.
ANSPSC receives information from the skin and skeletal muscles, whereas SSAA
integrates sensory information and forms and comprehends the stimulus. Difference in
primary somatosensory cortex Determines the size, texture, and relationship of parts.
-cortex (receive)
-association (analyze)
Ependymal cells - ANS- Ciliated epithelial cells lining the central cavities of the brain and
spinal column.
- Forming a permeable barrier between the CSF and nervous tissue
- beating cilia helps circulate the CSF
- secrete and circulate CSF
EPSP - ANSExcitatory Post Synaptic Potential
There are channels that allow sodium ions to move in the post synaptic neuron and this
causes depolarization and a graded potential = EPSP. We have a -70 RMP. The Na+ is
going to depolarize it. There is no AP in the soma so the Na+ is going to go the trigger zone.
We have an EPSP but since it does not reach threshold it is not sufficient enough to
generate an AP.
Explain a graded potential spreading locally. - ANSCations will move towards a negative
charge. The site next to the original depolarization event will also depolarize creating
another graded potential.
______ and _______ induce the formation of the BBB. - ANSAstrocytes and Pericytes
______ gated channels generate local, graded potentials. - ANSChemically gated channels
generate local potentials.
________ channels are found mainly on the axon and axon hillock (trigger zone). -
ANSVoltage gated channels
1st type of information provided by sensation receptors: modality - ANSType of stimulus or
the sensation it produces
-temp vs touch
-vibration vs sound
- by looking at your laptop you cannot tell how it tastes but you can see it.
2nd type of information: location - ANSEncoded by which nerve fibers are issuing signals to
the brain. Receptive fields tell the area covered by one single receptor.
3rd type of information: Intensity - ANSHow strong the stimulus is
A) as stimulus intensity rises, the firing frequencies of sensory nerve fibers rise (b) intense
stimuli recruit greater numbers of nerve fibers to fire; and (c) weak stimuli activate only the
most sensitive nerve fibers, whereas strong stimuli can activate a less sensitive group of
fibers with higher thresholds. Thus, the brain can distinguish intensities based on which
fibers are firing, how many are doing so, and how fast they are firing.
Duration - ANSPhasic receptors are the fourth kind of information: you're getting used to the
shirt you're wearing because they adapt quickly. - Notify on us change (onset and cessation
of the stimulus)
Tonic receptors are slow adapting receptors (e.g. pain does not go away)
- Notify on duration of the stimulus
A child eats a whole bottle of salt (NaCl) tablets. What effect does this have on the resting
membrane potential? - ANSAlthough there are leakage channels, the sodium permeability is
so low the change will be minor. Think about a lot of students outside a small door that
wants to get in, but they cannot all get through at once.
Absolute Refractory Period - ANSNa+ channels have not yet reset to the resting positions.
A new AP CANNOT be generated. (before the peak)
Action potentials can only be generated and propagated in ______ and _______. -
ANSNeurons (only at the axon) and muscles. Why?
Antagonistic control - ANSMost internal organs are innervated by both divisions of the ANS,
which exhibit antagonistic control
Ex; heart rate. increase in sympathetic stimulation causes HR to increase, parasympathetic
causes it to decrease
Astrocytes - ANS- support and brace neurons
- control the chemical environment
- cover the brain and nonsynaptic regions of neurons
- supportive framework of CNS
- induce BBB
- influence synaptic signaling
- secrete growth factors
, - removes K+ and some NTs from ECF of brain and spinal cord
- form scar tissue
At what point does an action potential become an all or none process? - ANSUpon reaching
the threshold
Auditory association area - ANSStores memories of sounds and permits perception of
sounds
Autonomic Nervous System - ANSConsists of motor neurons that:
- Make adjustments to ensure optimal support for body activities
- Operate via subconscious control
Bottom - visual cortex (blindness) - ANSallows you to see general shapes and shadows but
no identification
Broca's area - ANScontrols muscles involved in speech. Sends messages to the primary
motor cortex and this PMC tells muscles to contract, etc.
Present in one hemisphere.
Chemically (ligand) gated channels - ANSa ligand binds to receptor causing a
conformational change and opening the gate to the ions.
- can be specific or not specific (Ach at neural muscular junctions is permeable to all cations
- noth Na and K).
Chemoreceptors - ANSrespond to chemicals, including odors, tastes, and body fluid
composition.
Depolarize - ANSMaking the cell less polarized (closer to zero).
Describe the soma, neurofibrils, Nissl bodies, dendrites, axon and axon hillock. - ANSSoma-
body of the neuron cell.
Neurofibrils- work with microtubules to compartmentalize rough ER into Nissl bodies.
Nissl bodies- help identify neurons in tissue sections with mixed cell types
Dendrites- primary site for receiving signals from other neurons
axon hillock- nerve fiber where axon originates
axon- conducs nerve signals to remote point from the soma. contains Varicosities secrete
NTs.
ANSPSC receives information from the skin and skeletal muscles, whereas SSAA
integrates sensory information and forms and comprehends the stimulus. Difference in
primary somatosensory cortex Determines the size, texture, and relationship of parts.
-cortex (receive)
-association (analyze)
Ependymal cells - ANS- Ciliated epithelial cells lining the central cavities of the brain and
spinal column.
- Forming a permeable barrier between the CSF and nervous tissue
- beating cilia helps circulate the CSF
- secrete and circulate CSF
EPSP - ANSExcitatory Post Synaptic Potential
There are channels that allow sodium ions to move in the post synaptic neuron and this
causes depolarization and a graded potential = EPSP. We have a -70 RMP. The Na+ is
going to depolarize it. There is no AP in the soma so the Na+ is going to go the trigger zone.
We have an EPSP but since it does not reach threshold it is not sufficient enough to
generate an AP.
Explain a graded potential spreading locally. - ANSCations will move towards a negative
charge. The site next to the original depolarization event will also depolarize creating
another graded potential.
