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330 Cards in this Set
- Front
- Back
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A physical stimulus can create a bidirectional impulse in the axon, but what way will it continue to propagate?
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Towards the end of the axon (to the next neuron); it will not send from the dendrites to the axon terminals of the neuron before it
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What is the physical separation between neurons?
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Synapse
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How are impulses propagated between neurons?
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Neurotransmitters in synaptic vesicles are released into the synapse
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Is the electrochemical impulse identical is all neurons?
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Yes
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How can neurons be distinguished?
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- Information they carry
- Anatomical structure - Development |
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How does the development of neurons differ depending on whether the cell body is in or outside of the CNS?
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- Inside CNS: precursor germ layer - ectodermal neural tube
- Outside CNS: precursor germ layer - ectodermal neural crest |
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What differentiates general and special neurons based on location?
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- General - located all over body
- Special - restricted to certain body regions |
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General neurons have receptors where? to sense what?
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All over body:
- Touch - Pressure - Heat - Stretch |
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General neurons have effectors where? What kinds of muscle (origin)?
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All over body:
- Axial muscle - Smooth muscle (from mesoderm) |
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Special neurons have receptors where? to sense what?
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Restricted to certain body regions:
- Taste - Vision - Smell - Hearing |
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Special neurons have receptors where? What kind of muscle (origin)?
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Restricted to certain body regions
- Branchiomeric muscles (from neural crest) |
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What are the four general functional components of neurons?
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- GSA - general somatic afferent
- GVA - general visceral afferent - GVE - general visceral efferent - GSE - general somatic efferent |
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What two functional components of neurons are involved in sensory processing?
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GSA and GVA
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What two functional components of neurons are involved in the motor component?
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GVE and GSE
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Which functional component sends signals from the outer body wall to the DNS?
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GSA - general somatic afferent
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Which functional component of neurons sends signals from the inner body wall (gut) to the CNS?
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GVA - general visceral afferent
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Where are the cell bodies of afferent neurons?
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Outside of the CNS (GSA and GVA)
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Where are the cell bodies of efferent neurons?
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Inside of the CNS (GVE and GSE)
*although GVE also has cell body outside of CNS* |
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Which functional component of neurons sends signals from the CNS to the inner body wall (gut)?
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GVE - general visceral efferent
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Which functional component of neurons sends signals from the CNS to the outer body wall?
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GSE - general somatic efferent
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What is a ganglion? Which functional component of neurons is known to form these?
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Cluster of cell bodies outside of the CNS; usually near a synapse
GVE in mammals form ganglion (also GSA and GVA may form these) |
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GVE form ganglion; what is the term for the neuron with the cell body in the CNS? the neuron with the cell body in the ganglion?
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- In CNS - preganglionic neuron
- In GANGLION - postganglionic neuron |
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What distinguishes preganglionic neurons from postganglionic neurons besides the location of the cell body?
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- Preganglionic - always myelinated (looks white)
- Postganglionic - never myelinated (looks grey) |
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Which functional components of neurons are sensory?
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GSA GVA (afferent!!)
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Which functional component of neurons can NOT form ganglia?
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GSE
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Which functional components of neurons are motor neurons?
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GVE and GSE (effectors)
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What is a neuron fiber bundle called when it is inside of the CNS? outside of the CNS?
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Inside: Tract
Outside: Nerve |
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What is a cell body group called when it is inside of the CNS? outside of the CNS?
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Inside: Nucleus
Outside: Ganglion |
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What is a neuron mass called when it is inside of the CNS? outside of the CNS?
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Inside: Center
Outside: Plexus |
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What are myelinated fibers called when they are inside of the CNS? outside of the CNS?
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Inside: White Matter
Outside: White Rami |
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What are unmyelinated fibers called when they are inside of the CNS? outside of the CNS?
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Inside: Grey Matter
Outside: Grey Rami |
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What is the reference point for direction of an impulse?
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Brain
- to brain: ascending - from brain: descending |
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Association neurons form cell body masses in the CNS called what? How many are there? Called what?
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Columns: 3
- Dorsal - Lateral - Ventral |
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What is found in the dorsal column found in the spinal cord?
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Association neurons which receive information from sensory neurons (GSA and GVA)
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What is found in the ventral column found in the spinal cord?
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Association neurons which send information to motor neurons (GVE)
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What is found in the ventral column found in the spinal cord?
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Association neurons which send information to motor neurons (GSE)
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What is the route of the GSA from the outer, somatic, sensory location?
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- Enters spinal nerve through dorsal ramus or ventral ramus
- Leads into dorsal root - Ends in dorsal column |
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Where are the cell bodies of sensory neurons (GSA and GVA) located?
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Both in the Dorsal Root Ganglion (outside of the CNS)
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What is the route of the GVE from inside of the CNS?
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- Starts at the lateral column
- Enters the ventral root (with GSE) which connects to the spinal nerve - Leads into white visceral ramus (preganglionic neuron) - Sends signal to sympathetic chain ganglion (cell bodies of postganglionic neuron) - Posganglionic neuron leads through gray visceral ramus |
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What is the route of the GSE from inside of the CNS?
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-Starts at the ventral column
- Enters the ventral root (with GVE) which connects to the spinal nerve - Sends signal out to dorsal ramus or ventral ramus (epaxial and hypaxial) |
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What is the route of the GVA from its visceral location?
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- Passes through chain ganglion (where GVE postganglionic cell bodies are)
- Enters white visceral ramus which leads to spinal nerve - Leads into dorsal root (where cell body is located in dorsal root ganglion with GSA) - Ends at the dorsal column (with the GSA) |
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Which functional components of neurons are found in the spinal nerve?
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All four components (GSA, GVA, GVE, GSE)
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What are the functions of the autonomic nervous system?
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- Control of visceral function (internal organs)
- Involuntary functions (some cranial nerves of brain stem, spinal cord) |
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What functional component of neurons is seen in the autonomic nervous system?
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GVE only
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What is the embryonic origin of the structures of the autonomic nervous system?
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Visceral Hypomere
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What kind of information is sent by the autonomic nervous system
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Motor (effector)
- Smooth muscles or glands |
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What is meant by the "two-part" structure to each GVE neuron path?
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There is a preganglionic neuron (cell body in CNS) and a postganglionic neuron (cell body out of CNS)
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What two systems compose the autonomic nervous system?
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- Parasympathetic
- Sympathetic |
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Which system is responsible for relaxing the body, vegetative?
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Parasympathetic
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Which system is responsible for calling the body to action, vigilance, and the fight-or-flight response?
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Sympathetic
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Which kind of nerves are found in the parasympathetic nervous system?
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Cranial
Sacral |
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Which kind of nerves are found in the sympathetic nervous system?
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Thoracic
Lumbar |
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In the parasympathetic system, how do the length of the pre and post-ganglionic neurons compare?
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Pre-gang are longer than post-gang
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In the sympathetic system, how do the length of the pre and post-ganglionic neurons compare?
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Pre-gang are shorter than post-gang
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In which of the autonomic nervous systems are ganglia always paired?
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Parasympathetic
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Which kind of nerves are found in the parasympathetic nervous system?
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Cranial
Sacral |
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Which kind of nerves are found in the sympathetic nervous system?
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Thoracic
Lumbar |
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In the parasympathetic system, how do the length of the pre and post-ganglionic neurons compare?
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Pre-gang are longer than post-gang
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In the sympathetic system, how do the length of the pre and post-ganglionic neurons compare?
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Pre-gang are shorter than post-gang
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In which of the autonomic nervous systems are ganglia always paired?
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Parasympathetic
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In the sympathetic system of the autonomic nervous system are the ganglia paired or unpaired?
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They can be either paired or unpaired on either side of spinal cord
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Cranial, Sacral, Thoracic and Lumbar are made of what structural component of neurons?
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GVE
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What ganglia exists for the parasympathetic system?
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Cranial Nerve Ganglia
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What ganglia exist for the sympathetic system?
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Cervical Ganglia
Sympathetic Chain Ganglia Subvertebral Ganglia |
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What functions do the cranial nerves have?
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Parasympathetic System
- Constrict Pupil - Inhibits Lacrimal Gland - Inhibits Salivary Gland Secretion - Inhibits Heart - Constricts respiratory passages - Stomach motility and pancreatic secretion stimulated - Intestinal motility stimulated |
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What functions do the sacral nerves have?
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Parasympathetic System
- Intestinal motility stimulated - Constricts bladder - Dilates genital blood vessels |
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What functions do the thoracic nerves have?
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Sympathetic System
- Dilates pupils - Stimulates lacrimal gland - Stimulates salivation - Accelerates heart rate - Dilates respiratory passages - Stomach motility and pancreatic secretion inhibited - Stimulates adrenalin secretion |
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What functions do the lumbar nerves have?
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- Intestinal motility inhibited
- Relaxes bladder - Constricts genital blood vessels |
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Which of the cranial nerves are in the cranial nerve ganglia? Which is not?
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III, VII, IX are part of ganglia
X (Vagus) is not part of ganglia |
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Which ganglia of the autonomic nervous system are paired? Which is not paired?
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Paired: cranial nerve ganglia, cervical ganglia, sympathetic chain ganglia
Not paired: subvertebral ganglia |
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What are some defining features of the parasympathetic system?
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- "Intrinsic Ganglion"
- Cranial Ganglion - Vagus Nerve - Synapses: Acetylcholine |
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What are some defining features of the sympathetic system?
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- Sympathetic Chain Ganglion
- Subvertebral Ganglion - Cervical Ganglion - Neurotransmitters: epinephrine or norepinephrine |
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What is meant by the "intrinsic ganglion"? What system is it found in?
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Cell bodies of post-ganglionic neurons reside on the effected organ; found in parasympathetic system
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What characterizes the cranial ganglion? What system is it found in?
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- Ganglion of cranial nerve that contains GVE components
- Emerges from brain stem - 3 cranial nerves form it - Parasympathetic |
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What is important about the vagus nerve? What system is it found in?
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- 4th cranial nerve that contains GVE components
- 80% of parasympathetic innervation - All intrinsic ganglia |
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Which nerve is nicknamed the "wanderer"?
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Vagus (X) - 4th cranial nerve containing GVE; found in parasympathetic system
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Which neurotransmitters are characteristic of the parasympathetic system?
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Acetylcholine
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What forms the sympathetic chain ganglia? What system is it found in?
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- Pre- and Post-ganglionic neurons that synapse close to spinal cord
- Sympathetic |
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Which of the autonomic ganglia is unpaired? What system is it found in?
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Subvertebral Ganglion (3)
- Ventral location - Sympathetic |
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Where is the cervical ganglion found? What system is it found in? What characterizes it?
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Neck region
- Sympathetic system - Pre-ganglionic component emerges from cord in thoracid region and runs in sympathetic chain to anterior neck region |
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Which neurotransmitters are important to the sympathetic system?
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Epinephrine and Norepinephrine
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What is the path of the GVE neurons of the "Chain Ganglia" beginning at the CNS?
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- Travels through ventral root to spinal nerve
- Preganglionic neuron enters White Visceral Ramus and axon ends (synapse) in chain ganglia - Postganglionic neuron cell body begins at chain ganglia and sent viscerally |
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The "chain" ganglia of the sympathetic system does or does not enter the sympathetic chain?
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Does NOT
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What is the path of the GVE neurons of the "Cervical Ganglia" beginning at the CNS?
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- Travels through ventral root to spinal nerve
- Preganglionic neuron enters White Visceral Ramus and passes through to enter the sympathetic chain |
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What is the path of the GVE neurons of the "Subvertebral Ganglia" beginning at the CNS?
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- Travels through ventral root to spinal nerve
- Preganglionic neuron enters white visceral ramus, but does not enter the sympathetic chain or form chain ganglia - Synapses at unpaired subvertebral ganglion |
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What is the path of the GVE neurons in the "Grey Visceral Rami" pathway beginning at the CNS?
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- Leaves through ventral root and enters spinal nerve
- Leads into White Visceral Ramus and ends in chain ganglia (synapse) - Postganglionic cell body in cell ganglia, heads through grey visceral ramus back into the spinal nerve - Leaves towards dorsal ramus (control of skin/blood vessels of outer body wall) |
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What do the following colors correspond to: blue, green, orange, red?
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- Blue - GSA
- Green - GVA - Orange - GVE - Red - GSE |
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The path to the adrenal glands by GVE is for what system? Why is is it significant?
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Sympathetic System
- A single preganglionic neuron travels from the CNS to the adrenal gland (medulla) |
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When the preganglionic GVE neuron reaches the medulla of the adrenal gland, what happens?
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Secretes catecholamines directly into the blood (adrenaline and noradrenaline)
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What is the medulla of the adrenal gland?
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A modified "mass of" post-ganglionic neurons of GVE
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Where is chromaffin tissue? What is its origin?
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Found in medulla of adrenal gland (postganglionic neurons of GVE)
Neural Crest origin |
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What surrounds the medulla of the adrenal gland?
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Cortex
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What is produced within the medulla of the adrenal glands?
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Epinephrine and norepinephrine
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What is the function of the one neuron path of GVE to the adrenal gland?
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- Neurotransmitters act as hormones because they have a longer-duration effect and act globally by activating all systems
- Useful for threats or short-term challenges |
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What are the two roots of mammalian spinal nerves? What is found in each root?
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- Dorsal Root (sensory - GSA and GVA)
- Ventral Root (motor - GVE and GSE) |
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Are the spinal nerves segmental or intersegmental in mammals?
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Segmental, as are myotome (vertebrae are intersegmental)
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In amphioxus and lamprey, how are the components of the spinal nerve organized?
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- Dorsal Nerve: GSA, GVA, GVE
- Ventral Nerve: GSE - These alternate down the length of the body - No roots - No regional differentiation |
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What does the spinal nerve evolve from?
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Joining of the dorsal and ventral nerves (that are seen in amphioxus and lampreys)
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The dorsal nerve is homologous to what evolved structure?
The ventral nerve is homologous to what evolved structure? |
Dorsal Root
Ventral Root |
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How are the dorsal nerves and ventral nerves arranged in amphioxus and lampreys?
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- Dorsal nerves are located intersegmentally with vertebrae
- Ventral nerves are located segmentally with myotome |
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From dorsal to ventral, what is the order of the functional components of neurons?
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GSA, GVA, GVE, GSE
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What happens to Hagfish in the early evolution of spinal nerves?
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The Dorsal nerve shifts closer to the Ventral nerve (but still no roots)
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In what species is the first appearance of ventral/dorsal roots and the spinal nerve?
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Sharks
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How are the functional components of neurons organized in sharks?
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Dorsal Root: GSA, GVA, GVE
Ventral Root: GSE ---> All located segmentally now run into spinal nerve |
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How does the 3:1 arrangement of the dorsal/ventral roots transition to the 2:2 arrangement?
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In bony fish and some amphibians, the GVE component is duplicated (3:2); it appears in both the dorsal and ventral roots:
Dorsal Root: GSA, GVA, GVE Ventral Root: GVE, GSE |
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When does the 2:2 arrangement of the dorsal/ventral roots first occur?
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In Amniotes (mammals)
Dorsal Root: GSA, GVA (GVE lost here) Ventral Root: GVE, GSE |
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Which nerves are characterized by "double-innervation"? Which vertebrates have this distinction?
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Effectors (GVE, GSE) by sympathetic and parasympathetic systems
- Constant in ALL vertebrates |
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What are characteristics of the exit patterns of GVE from cord (of autonomic N.S.) in amphioxus?
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- No regional distinction between sympathetic and parasympathetic systems
- All ganglia are intrinsic - GVE components emerge from cord even in cervical region |
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What evolutionary step happens to cyclostomes (not in amphioxus) in regards to their autonomic nervous system structures?
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- GVE component in 1 cranial nerve begins to branch/wander (Vagus)
- Otherwise the same as amphioxus |
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What evolutionary patterns occur in sharks (that were not present in amphioxus or cyclostomes) in regards to the autonomic N.S.?
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- No GVE from cervical region
- No longer intrinsic ganglia in cranial region (except vagus) - GVE of sympathetic system (thoracic region) synapse closer to cord (not always intrinsic) - Otherwise same (most ganglia intrinsic (Vagus, Lumbar, Sacral) |
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What evolutionary patterns occur in bony fish (that were not present before (amphioxus, cyclostomes, sharks) in regards to the autonomic N.S.?
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- Formation of sympathetic chain in thoracic and lumbar regions
- Parasympathetic (cranial and sacral) remain the same as in sharks (not intrinsic ganglia cranially, except wandering vagus; intrinsic in sacral region) |
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There are up to how many cranial nerves? What three groups do they fit into?
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Up to 13 (0-XII); only amniotes have XI and XII
- Branchial - Sensory - Motor |
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What do the following colors correspond to for cranial nerves? What are the homologies?
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Orange - branchial - dorsal nerve
Red - motor - ventral nerve Black - sensory - unique cranial receptors (not homologous to anything) |
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Which of the Cranial Nerves are designated "Branchial"?
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0 - neurons terminales
V - trigeminus VII - facialus IX - glossopharyngeal X - vagus XI - spinal accessory |
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Which of the Cranial Nerves are designated "Sensory"?
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I - olfactory
II - optic VIII - auditory (not always for hearing) |
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Which of the Cranial Nerves are designated "Motor"?
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III - oculomotor
IV - trochlear VI - abducens XII - hypoglossal |
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What is cranial nerve XI (spinal accessory) homologous to?
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"accessory" to Vagus (part of)
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What is cranial nerve XII (hypoglossal) homologous to?
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Homologo of cervical spinal nerve
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Which "cranial" nerves were originally cervical spinal nerves that were "captured" by the expanding cranium?
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XI and XII (which are only cranial nerves in amniotes)
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What are the 7 functional components of neurons seen in cranial nerves?
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GSA, GVA, GVE, GSE
New: special components not found all over body: SVA, SSA, SVE (no SSE) |
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Sensory Cranial nerves are always what functional component? What does that tell us?
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Special somatic afferent (SSA)
- Special - only found in head - Somatic - outer body - Afferent - carries information to the CNS |
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What are the cranial nerves in order from 0-XII?
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0 - Neuron Terminales
I - Olfactory II - Optic III - Oculomotor IV - Trochlear V - Trigeminus VI - Abducens VII - Facialus VIII - Auditory IX - Glossopharyngeal X - Vagus XI - Spinal Accessory XII - Hypoglossal |
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What is unique about the structure of olfactory nerve (I) cells?
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Made of neurosensory cells which combine both the receptor and conductor on one structure; receptor of SSA located on neural tube, which connects to conductor inside of CNS)
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How thick are the neurosensory cells?
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1 cell layer thick in olfactory epithelium in nose
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Where are neurosensory cells found?
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Olfactory Epithelium
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What structure holds the olfactory epithelium outside of the CNS?
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Olfactory Sac, which is attached to the Olfactory Bulb which sends impulses down the Olfactory Tract to the Olfactory Lobe
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What type of neurons run from cranial nerve I to CNS center (olfactory lobe)?
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Association neurons
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What is the process of getting visual stimulus to the brain?
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- Photons hit the retinal photoreceptors (1 cell layer thick)
- Association neurons (Optic Nerve, II) take impulse to brain |
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What is the difference between the Optic Nerve (II) in submammalian vertebrates and higher primates?
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- Before mammals the left eye went completely to the right side of brain and right eye went to left brain
- Higher primates both eyes go to each side of brain |
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Where does the optic nerve (II) reside?
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All parts inside the CNS, derived from neural tube
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What is the function of the auditory nerve (VIII)?
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Relates to pressure waves
- Hearing in amniotes - Movement and balance in other vertebrates - Combined |
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What is cranial nerve VIII called in vertebrates other than amniotes where it functions in movement and balance?
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"Vestibulo-Cochlear Nerve"
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What was cranial nerve VIII originally involved in?
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Lateral Line System (LLS)
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What structures exist in the Lateral Line System?
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- Pits and canals (sense organs) in head, line down body
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What is the name for the Lateral Line System receptor? How does it work?
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Neuromast cell - pressure wave deforms cupula (part sticking out) which stimulates the neurons
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What did the Lateral Line System evolve from?
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Ectodermal placodes (4) (not olfactory placodes); outside of neural tube
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What is the functional component of the Lateral Line System?
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SSA
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Which cranial nerves are involved in the Lateral Line System for Fish? for Tetrapods?
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Fish: VII - X
Tetrapods: VIII only |
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What do ectodermal placodes 1-4 correspond to? What do they become?
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1: C.N. VII - LLS in head
2: C.N. VIII - LLS in head 3: C.N. IX - LLS in head 4: C.N. X - LLS along body |
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What happens to the SSA from placode 2?
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Becomes cranial nerve VIII in fish and tetrapods
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What happens to the SSA from placodes 1,3,4?
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Becomes functional components of adjacent cranial nerves when LLS present (fish)
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Embryonically, what is the structure of the ectodermal placode?
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Straddles surface (green on outside, blue on inside)
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What happens to the green portion of the ectodermal placode outside of the surface? The blue portion inside the surface?
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Green - forms neuromast cells
Blue - forms SSA sensory neurons which connect to CNS; forms ganglion outside of CNS |
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Ancestrally, which functional components of nerves were involved in the dorsal nerve? What did this become?
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GSA, GVA, GVE
--> Branchial, Cranial Nerve |
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Ancestrally, which functional component of nerves was involved in the ventral nerve? What did this become?
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GSE
--> Motor Cranial Nerve (ventral refers to being located under the cranium) |
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In the derived form, which functional components of nerves were involved in the dorsal root? What did this become?
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GSA, GVA
--> Spinal Nerve |
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In the derived form, which functional components of nerves were involved in the ventral root? What did this become?
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GVE, GSE
--> Spinal Nerve |
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Which nerves retain the ancestral arrangement of neurons, even in derived forms? Why is this odd?
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Branchial and Motor Cranial Nerves
- Paradox because head retains ancestral form |
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What functional component innervates eye muscles? What do the muscles develop from?
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GSE
- develops from pre-otic segments of myotome |
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What cranial motor nerves innervate the three pre-otic myotome segments of muscle?
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Segment 1: III (oculomotor)
Segment 2: IV (trochlear) Segment 3: VI (abducens) |
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For the post-otic myotome, what are the four muscle segments called which are located dorsally? Ventrally?
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Dorsally: Epibranchials
Ventrally: Hypobranchials |
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What functional component of neurons innervates the epibranchials and hypobranchials?
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GSE of cervical spinal nerve
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In amniotes, which cranial nerve innervates the tongue? What is unique about this?
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Cranial Nerve XII (used to be a hypobranchial, cervical spinal nerve which was captured by the expanding cranium)
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What three motor cranial nerves are shared by all vertebrates?
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Oculomotor (III), Trochlear (IV), Abducens (VI)
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Why are "branchial" cranial nerves named branchial?
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Because they associate with branchial/visceral structures (visceral arches)
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Which nerves are derived from ancestral pharynx or gill arches?
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Branchial Cranial Nerves
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What is the homology of the branchial cranial nerves?
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Ancestral dorsal nerve
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Which functional components persist in branchial cranial nerves?
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GSA, GVA, GVE (no GSE)
and special components which correspond to each general component SSA, SVA, SVE; not all are always present |
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Which kind of nerves may have one or more functional components running separately out of the cranium?
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Branchial Cranial Nerves
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What is the homology of the Branchial Cranial Nerve 0? What is its name in humans? Which functional components remain?
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- Ancestral dorsal nerve
- Terminal - Only GSA remains (1 of 6) |
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What is the homology of the Branchial Cranial Nerve V? What is its name in humans? Which functional components remain? What is special about it?
|
- Fusion of two or more ancestral dorsal nerves
- Trigeminal - 3 functional components remain of 6 - 3 physical branches |
|
|
What is the homology of the Branchial Cranial Nerves VII, IX, and X? What are their names in humans? Which functional components remain?
|
- Complete ancestral dorsal nerves
- Facial (VII), Glossopharyngeal (IX), Vagus (X) - All 6 functional components remain |
|
|
What is the homology of the Branchial Cranial Nerve XI? What is its name in humans? Which functional components remain?
|
- Derived from vagus
- Spinal Accessory - SVE is only remaining component, found separate from the cranium |
|
|
What are the anatomical structures of a branchial cranial nerve?
|
- Dorsal Ramus
- Pretrematic Ramus - Posttrematic Ramus |
|
|
The dorsal ramus of branchial cranial nerves is composed of what functional components?
|
Sensory: GSA, SSA
|
|
|
The pretrematic ramus of branchial cranial nerves is composed of what functional components?
|
Sensory: GVA, SVA
|
|
|
The posttrematic ramus of branchial cranial nerves is composed of what functional components?
|
Sensory: GVA, SVA
Motor: GVE, SVE |
|
|
Where is the pretrematic ramus located? The posttrematic ramus?
|
Pretrematic - anterior to the pharyngeal slit
Posttrematic - posterior tot he pharyngeal slit |
|
|
The SSA component is involved in what branchial cranial nerves?
|
VII, IX and X (from neuromast)
|
|
|
The SVA functional component is seen in which branchial cranial nerves? And what structure more generally?
|
VII, IX and X (taste buds)
|
|
|
SVE is also known as what? What branchial cranial nerves is it seen in?
|
Efferent Branchial (EB)
- V, VII, IX, X, XI (branchiomeric muscles) |
|
|
The terminal nerve (0) originally was used to supply what structure?
|
Most anterior pharyngeal arch which was lost early in vertebrate evolution
|
|
|
The Trigeminal nerve (V) originally was used to supply what structure?
|
Mandibular Arch (VA I, 0')
Added component from anterior arch (VA 0) |
|
|
The Facial nerve (VII) originally was used to supply what structure?
|
Hyoid arch (VA II, arch "S")
|
|
|
The glossopharyngeal nerve (IX) was originally used to supply what structure?
|
Supplied VA III, arch 1
|
|
|
The Vagus nerve (X) and the Spinal Accessory nerve (XI) were originally used to supply what structure?
|
Visceral Arches IV-VII (arches 2-5)
|
|
|
What are the three branches fo the trigeminal?
|
V1: Opthalmic - superficial (So) and deep (Do)
V2: Maxillary - infraorbital (In) in fish V3: Mandibular - (Md) |
|
|
What is the cutaneous distribution of the trigeminal nerve?
|
V1 - crown of head, eyes, nose
V2 - upper jaw (VA I) V3 - lower jaw (VA I) |
|
|
GSA of the branchial cranial nerves is from what?
It is found where for V, VII, IX, X, XI? |
Exteroceptors in skin (neural crest)
V: Head VII: Head, minor cutaneous IX: Head, minor cutaneous X: Neck, minor cutaneous XI: not present |
|
|
SSA of the branchial cranial nerves is from what?
It is found where for V, VII, IX, X, XI? |
From Lateral Line System (Ectodermal Placodes)
V: not present VII: 1st ectodermal placode IX: 3rd ectodermal placode X: 4th ectodermal placode XI: not present |
|
|
GVA of the branchial cranial nerves is from what?
It is found where for V, VII, IX, X, XI? |
From enteroreceptors in mouth/pharynx (neural crest)
V: not present VII: anterior IX: mid mouth; anterior pharynx X: posterior mouth; pharynx; larynx; trachea XI: not present |
|
|
SVA of the branchial cranial nerves is from what?
It is found where for V, VII, IX, X, XI? |
Taste buds (neural crest)
V: not present VII: anterior tongue IX: posterior tongue X: epiglottis and palate XI: not present |
|
|
GVE of the branchial cranial nerves is going to where?
It is found where for V, VII, IX, X, XI? |
To involuntary muscles and glands-para-sympathetic
V: pupillary muscle innervation? VII: salivary glands, lacrimal glands IX: salivary glands X: major parasympathetic outflow to visceral organs XI: not sure of |
|
|
SVE of the branchial cranial nerves is going to where?
It is found where for V, VII, IX, X, XI? |
To branchiomeric muscles of visceral arches
V: mastication (1st VA) VII: facial muscles, stapedial, hyoid apparatus (2nd VA) IX: pharynx and larynx (3rd VA) X: pharynx, larynx, trapezius complex (4th-7th VA) XI: accessory to vagus, physically part of vagus (4th-7th VA) |
|
|
How do SVE and GVE differ in branchial cranial nerves?
|
SVE - voluntary, striated muscle
GVE - involuntary (autonomic nervous system) |
|
|
What is the swelling of the anterior CNS?
|
Brain
|
|
|
The central nervous system (CNS) is derived from what?
|
Neural Tube which is hollow, just all folded up
|
|
|
What is the swelling in size of the anterior CNS (brain) caused by?
|
Proliferation of neurons and their cell bodies
|
|
|
How does the brain increase in complexity?
|
Proliferation in nuclei (cell body mass, ganglia) and centers (neuron mass, plexus)
|
|
|
What does the brain differentiate into early in development?
|
Three primary vesicles
|
|
|
What are the three earliest swellings of the neural tube called?
|
Primary vesicles:
Prosencephalon (forebrain) Mesencephalon (midbrain) Rhombencephalon (hindbrain) |
|
|
What are the five swellings of the brain which are derived from the primary vesicles?
|
Secondary vesicles:
Telencephalon Diencephalon Mesencephalon Metencephalon Myelencephalon |
|
|
Which secondary vesicles are found in the Prosencephalon?
|
Telencephalon
Diencephalon |
|
|
Which secondary vesicle is found in the Mesencephalon?
|
Mesencephalon
|
|
|
Which secondary vesicles are found in the Rhombencephalon?
|
Metencephalon
Myelencephalon |
|
|
The forebrain, prosencephalon, is involved in what functions?
|
Olfaction (smell brain)
|
|
|
The midbrain, mesencephalon, is involved in what functions?
|
Vision (eye brain)
|
|
|
The hindbrain, rhombencephalon, is involved in what functions?
|
Hearing (ear brain)
Balance |
|
|
What do the four roman numeral (I-IV) designate in the brain?
|
Ventricles
I&II - telencephalon (cerebral hemispheres) III - diencephalon (thalamus) IV - myelencephalon (medulla oblongata) |
|
|
What connects ventricles III and IV? What structures does it run past/through?
|
Aqueduct
- cerebellum and optic lobes |
|
|
Which centers develop from the secondary vesicles?
|
- Telencephalon--> Cerebral Hemispheres
- Diencephalon--> region of Thalamus - Mesencephalon--> optic lobes (corpora bigemina) - Metencephalon--> cerebellum - Myelencephalon--> Medulla Oblongata |
|
|
What is the hollow neural tube filled with? Why?
|
Cerebrospinal fluid - for brain cell metabolism and nutrition
|
|
|
What is the choroid plexus? What is its function?
|
Highly folded ventricle (III and IV) wall; maximizes exchange between brain and cerebrospinal fluid
|
|
|
What three structures make up the diencephalon (Ventricle III)?
|
- Epithalamus
- Thalamus - Hypothalamus |
|
|
What structure makes up the roof of ventricle III?
|
Epithalamus
|
|
|
What structures are in the epithalamus? What are their functions?
|
- Pineal Organ - light sensitive endocrine organ
- Choroid Plexus - involved in metabolism - Habenula - olfaction input |
|
|
What structure makes up the paired nuclei on the lateral walls of ventricle III?
|
Thalamus
|
|
|
Where is the mass intermedia found? Does it contain decussating fibers?
|
Thalamus - no decussating fibers
|
|
|
What structure makes up the floor of ventricle III? What is its function?
|
Hypothalamus - major reflex control of autonomic nervous system; neurohormone secretions
|
|
|
What do the neurohormone secretions of the hypothalamus target?
|
Pituitary gland and Gonads
|
|
|
The cerebral hemispheres of cyclostomes are ventricles I and II; what matter surrounds them as viewed from the cross-section?
|
Hollow ventricle surrounded by grey matter (inside) and white matter (outside)
|
|
|
The cerebral hemispheres of derived vertebrates are ventricles I and II; what matter surrounds them as viewed from the cross-section?
|
Hollow ventricle surrounded by white matter (inside) and grey matter (outside)
|
|
|
What is the grey matter surrounding ventricles in the telencephalon called?
|
Pallium
|
|
|
What are the earliest centers to evolve in telencephalon called? What is it considered?
|
Pallia - the higher brain center
|
|
|
In cyclostomes, where is information processing done?
|
Mesencephalon
|
|
|
What is the function of the pallium in the cyclostome brain?
|
Sends information to mesencephalon from nose
|
|
|
The thickening roof of the mesencephalon is called what?
|
Tectum
|
|
|
What is the function of the tectum (of the mesencephalon)?
|
Integrates information and sends commands to the tegmentum
|
|
|
What is the thickening floor (ventral component) of the mesencephalon called?
|
Tegmentum
|
|
|
What is the function of the tegmentum?
|
Sends motor commands to body
|
|
|
The tectum receives four main streams of information; which components are involved and where are they from?
|
GVA - nose via pallium
GSA - eye GVE - lateral line GSA and GVA - general sensory information |
|
|
The cerebral hemispheres in sharks and amphibians have what structure?
|
- Hollow ventricles I and II in center
- Grey matter (composed of pallium, subpallium, and striatum) Outer white matter layer |
|
|
The grey matter of the cerebral hemispheres (telencephalon) in sharks and amphibians is broken down into three sections; what are the locations and which are ancestral, which are derived?
|
Pallium - dorsal - ancestral
Subpallium - lateral - derived Striatum - medial - derived |
|
|
What is the function of the pallium and subpallium of the grey matter in sharks and amphibians?
|
Olfaction
|
|
|
What is the function of the striatum of the grey matter in sharks and amphibians?
|
First center in telencephalon to integrate various information; not just for olfaction
|
|
|
What three centers are in the telencephalon of sharks through amphibians?
|
- Pallium
- Subpallium - Striatum |
|
|
What characteristic makes the sharks through amphibian brain no longer just a "reflex" brain (like in cyclostomes)?
|
- Forebrain acts as the seat of integration via the striatum (receives information from pallium and subpallium)
|
|
|
Which structure sends information to the striatum in the telencephalon? Which structure receives information from it?
(sharks to amphibians) |
- Dorsal lobe of thalamus sends to striatum
- Striatum sends to ventral lobe of thalamus |
|
|
What are the two lobes of the thalamus in sharks through amphibians?
|
Dorsal Lobe
Ventral Lobe |
|
|
The ventral lobe of the thalamus sends information where (sharks to amphibians)?
|
- Tectum (sensory)
- Hindbrain (motor) - both of mesencephalon |
|
|
What structure is found in the metencephalon of sharks to amphibians? What is its function?
|
Cerebellum
- coordinates motor commands - enhances motor skills |
|
|
Where does the Dorsal Lobe of the Thalamus receive signals from (sharks to amphibians)?
|
The Tectum (dorsal side of mesencephalon)
|
|
|
What are the four centers in the cerebral hemispheres of reptiles (telencephalon)?
|
Ancestral: pallium subpallium, striatum
Derived: neopallium |
|
|
How do the cerebral hemispheres and cerebellum change throughout amniotes (reptiles-birds-mammals)?
|
Reptiles - hemispheres do not cover other brain regions
Birds - start increasing in sign, covers other regions Mammals - greatly enlarged cerebral hemispheres and cerebellum |
|
|
The cerebral hemispheres in birds are homologous to what structure? Mammals?
|
Birds - homolog of striatum
Mammals - homolog of neopallium *Bird and Mammal cerebral hemispheres are NOT homologs* |
|
|
What are the four lobes of the mammal neocortex?
|
- Frontal
- Temporal - Parietal - Occipital (informal landmarks, no simple homology to ancestral centers) |
|
|
Which structure in the mammal neocortex is a huge mass of white matter?
|
Corpus Callosum
|
|
|
Which special neurons are found in the corpus callosum, which are integral to its function?
|
Decussating association neurons - bridge that allows information to transfer between cerebral hemispheres
|
|
|
What matter is on the outside? Which is on the inside of the mammalian neocortex?
|
Grey outside
White inside |
|
|
Which structures of the mammalian neocortex are homologous to the subpallium, striatum, pallium?
|
Subpallium --> head of caudate nucleus and putamen
Striatum --> Globus Pallidus Pallium --> hippocampus |
|
|
What are the embryonic components of the urogenital system?
|
Mesomere:
- Nephrogenic Mesomere - Genital Ridge |
|
|
What is the mesomere?
|
- Component of the mesoderm
- Embryonic ribbon of tissue that develops into components of the urogenital system |
|
|
What does the nephrogenic mesomere give rise to?
|
Excretory structures - kidney
|
|
|
What does the genital ridge give rise to?
|
Reproductive structures - "sexual kidney"
|
|
|
Which of the components of the mesomere is located more medially? Which is located more laterally?
|
Medial: Genital Ridge
Lateral: Nephrogenic Mesomere |
|
|
What are the two main layers of kidneys of amniotes?
|
- Outer: Renal Cortex ("bark")
- Inner: Renal Medulla ("body") |
|
|
What is the functional excretory unit?
|
Nephron
|
|
|
What structures of the nephron are located in the outer renal cortex?
|
- Renal corpuscle: Glomerulus and Bowman's Capsule
- Renal Tubule: Proximal and Distal Convoluted Tubules |
|
|
What makes up the renal corpuscle?
|
- Glomerulus
- Bowman's Capsule |
|
|
What are the names of the two arteries leaving the glomerulus?
|
Afferent and Efferent (heads towards medulla) Glomerular Arterioles
|
|
|
What is the indentation called in the kidney where the renal artery, renal vein, and ureter enter the kidney?
|
Hilus
|
|
|
What is the glomerulus?
|
Structure in the renal corpuscle; made of ball of capillaries; part of circulatory system
|
|
|
What is the Bowman's Capsule?
|
Part of Renal Corpuscle; mit surrounding the glomerulus that receives fluids from blood/glomerulus; part of nephron
|
|
|
What is the pathway of excretion through the kidney starting at the Bowman's Capsule?
|
- Enters renal tubule
- Proximal Convoluted tubule - Loop of Henle (extends into medulla) - Distal Convoluted tubule - Collecting tubule (extends into medulla) |
|
|
What is the sight of physiologiacl action in the kidney?
|
Renal tubule of the nephron
|
|
|
What are the two main layers of kidneys of amniotes?
|
- Outer: Renal Cortex ("bark")
- Inner: Renal Medulla ("body") |
|
|
What is the functional excretory unit?
|
Nephron
|
|
|
What structures of the nephron are located in the outer renal cortex?
|
- Renal corpuscle: Glomerulus and Bowman's Capsule
- Renal Tubule: Proximal and Distal Convoluted Tubules |
|
|
What makes up the renal corpuscle?
|
- Glomerulus
- Bowman's Capsule |
|
|
What are the names of the two arteries leaving the glomerulus?
|
Afferent and Efferent (heads towards medulla) Glomerular Arterioles
|
|
|
What is the indentation called in the kidney where the renal artery, renal vein, and ureter enter the kidney?
|
Hilus
|
|
|
What is the glomerulus?
|
Structure in the renal corpuscle; made of ball of capillaries; part of circulatory system
|
|
|
What is the Bowman's Capsule?
|
Part of Renal Corpuscle; mit surrounding the glomerulus that receives fluids from blood/glomerulus; part of nephron
|
|
|
What is the pathway of excretion through the kidney starting at the Bowman's Capsule?
|
- Enters renal tubule
- Proximal Convoluted tubule - Loop of Henle (extends into medulla) - Distal Convoluted tubule - Collecting tubule (extends into medulla) |
|
|
What is the sight of physiological action in the kidney?
|
Renal tubule of the nephron
|
|
|
What is the role of the collecting tubule?
|
- Collects kidney filtrate and physically removes it from the kidney via the ureter
|
|
|
How are nephrons characterized?
|
- Type of renal corpuscle
- Type of renal tubule - # of nephrons per body segment |
|
|
What characterizes a primary nephron?
|
- Derived from coelom
- Glomerulus present - 1 Nephron per body segment |
|
|
What two types of primary nephrons are there?
|
- External Glomerulus
- Internal Glomerulus |
|
|
What is the difference between an external and internal glomerulus?
|
External - glomerulus is not in a Bowman's capsule; found in coelom wall; blood products dumped into coelom; enters nephron via nephrostome, then to collecting duct
Internal - glomerulus is encased in Bowman's capsule; nephrostome persists but not functional; blood products enter renal tubule directly via Bowman's, then to collecting duct |
|
|
External glomerulus are found where? What kind of nephrons?
|
In wall of coelom
ONLY primary nephrons |
|
|
Internal glomerulus are found where? What kind of nephrons?
|
In Bowman's capsule
Both Primary and Secondary Nephrons |
|
|
Which kind of nephrons have functional nephrostomes?
|
(Primary) External Nephrons
|
|
|
What is the nephrostome?
|
Ciliated funnel from coelom to renal tubule; blood products dumped into coelom
|
|
|
In which kind of neuron is the nephrostome absent?
|
Secondary Nephron
|
|
|
Secondary nephrons develop from what?
|
Mesomere only
|
|
|
Secondary nephrons always have what structure which is not always present in primary nephrons?
|
Bowman's capsule is always present for secondary nephrons
|
|
|
How is the coelom important to secondary nephrons?
|
It plays no role
|
|
|
Why type of nephron has multiple nephrons per body segment? Which has only one nephron per segment?
|
Many - secondary
One - primary |
|
|
Which type of kidney develops from entire length of mesomere; looks like an elongated ribbon of tissue?
|
Archinephric Kidney
|
|
|
Which type of nephrons are found in archinephric kidneys?
|
Primary External Nephrons
- External glomerulus (in coelom) - Functional nephrostome - 1 nephron per body segment (10 total) |
|
|
How does blood flow through an archinephric kidney?
|
- Descends down aorta and enters external glomerulus
- Enters coelomic space and taken up at nephrestome - Continues through renal tubule and collecting tubule/duct - Drains into archinephric duct to the cloaca where it leaves the body |
|
|
What is the function of the archinephric duct?
|
Physically eliminates wasted produced by functional kidney
|
|
|
Which type of vertebrate has an archinephric kidney?
|
Hagfish - embryo only
|
|
|
What characterizes a Pronephric Kidney?
|
Does not extend down entire body; just found at top/cephalic end (below is undifferentiated nephrogenic mesoderm
|
|
|
What type of nephrons are found in pronephric kidneys?
|
Primary External
- External Glomerulus (in coelom) - Functional nephrostome - 1 nephron per body segment |
|
|
How are collecting ducts named?
|
Based on the kidney type
|
|
|
Which type of vertebrates have pronephric kidneys?
|
Fish and amphibians; embryonically
|
|
|
What characterizes a Mesonephric Kidney?
|
Functional component of mesoderm is in middle portion of original kidney
|
|
|
What is the kidney called if the middle and caudal end of the mesoderm develop?
|
Opisthonephric Kidney
|
|
|
What type of nephrons are found in mesonephric and opisthonephric kidneys?
|
Secondary Internal (mostly); Primary Internal (anterior portion)
- Internal glomerulus (in bowman) - No nephrostome - Multiple nephrons/body segment when secondary |
|
|
Which type of vertebrates have mesonephric/opisthonephric kidneys?
|
Hagfish adults
Shark adults Urodele adults |
|
|
How does the Metanephric Kidney develop?
|
- Begins at caudal end of mesomere
- Displaced laterally - Caudal end of mesophrenic duct buds out to join displaced mesomere - Functional kidney is displaced meosomere |
|
|
What does the mesonephric duct bud to become in the metanephric kidney?
|
Ureter
|
|
|
When the mesonephric kidney is completely translocated laterally, what is it called?
|
Metanephric kidney
|
|
|
What type of nephron are found in metanephric kidneys?
|
Secondary internal
- Glomerulus in Bowman's capsule - Nephrostome completely absent - Multiple nephrons/body segment |
|
|
What type of kidneys are Primary External?
|
Archinephric
Pronephric |
|
|
What type of kidneys are Primary Internal?
|
Anterior part of mesonephric and opisthonephric kidneys
|
|
|
What type of kidneys are Secondary Internal?
|
Most of mesonephric and opisthonephric kidneys (besides anterior portion)
Metanephric Kidneys |
|
|
What is the name of the collecting duct in metanephric kidneys?
|
"Metanephric Duct" is the Ureter
|
|
|
Which type of vertebrates have metanephric kidneys?
|
Amniote adults only
- embryo has function mesonephros (prior to complete translocation and extension of duct to be come ureter) |
|
|
What component of the excretory system takes on reproductive function?
|
Sexual Kidney
|
|
|
What are the two structures of the sexual kidney?
|
- Sexual Kidney Proper = "Genital Ridge"
- Kidney ---> Sexual Kidney (initially excretory structure, nephron, that switches to reproductive function) - Sexual kidney composed of both these |
|
|
What occurs in the two stages of the sexual kidneys development?
|
1. Tubule starts to form from renal corpuscle
2. Tubule grows down into genital ridge, now called efferent ductule |
|
|
When the tubule extending from the kidney attaches to the genital ridge, what is it called?
|
Efferent Ductule
|
|
|
Why are the tubules longer cranially?
|
They develop cranially (where genital ridge is next to kidney-forming mesomere)
|
|
|
The efferent ductules (from kidney to genital ridge) are called what in the male sexual kidney?
|
Epididymal Tubules which flow into Epididymal Duct
|
|
|
What once was the "collecting duct" of the kidney, is now called what in the male sexual kidney?
|
Vas Deferens
|
|
|
What is the function of the epidiymus? What two structures form it?
|
Carries sperm
- Epididymal tubules and epididymal duct |
|
|
What is the Vas Deferens homologous to? What is its function?
|
Collecting duct
- Carries sperm |
|
|
What is the sac for sperm storage called?
|
Seminal Vesicle
|
|
|
Because the kidney and sexual kidney evolve to use the same tube (collecting duct/vas deferens) what are the two options? Which vertebrates use that method?
|
- Evolve new duct for sperm - some fish
- Evolve a new duct for waste - some fish and amniotes |
|
|
What are the evolutionary steps towards evolving a new duct for sperm?
|
Sturgeon - marginal canal to gonad (connets to duct
Polypterus - greater separation, still connected Teleost - complete separation (sperm duct is not homologous to collecting duct) |
|
|
Is the sperm duct of teleosts (ray-finned fish) homologous to the collecting duct?
|
No... collecting duct is still attached to kidney
|
|
|
Teleosts sperm duct is noted to NOT be derived from what two things?
|
- sexual kidney
- epididymus *these structures are not present in teleosts* |
|
|
In some fish and amniotes, what are the three evolutionary steps towards evolving a new duct for waste?
|
- Initially, sperm and waste exit through vas deferens together
- Dogfish have accessory urinary duct for waste Amniotes have ureter for waste (completely separate) |
|
|
What are the two separate structures which evolve for waste transport in some fish and amniotes?
|
Some fish - accessory urinary duct
Amniotes - ureter |
|
|
Why is it important to evolve either a new duct for sperm or a new duct for waste?
|
Don't want to collect gametes and waste together
|
|
|
The embryonic gonad has an outer layer and an inner center, what are the names and which gender uses them for what?
|
Outer - Cortex - female function, making eggs
Inner - Medulla - male function, making sperm |
|
|
Where is the embryonic gonad located?
|
In the hypomere of the genital ridge
|
|
|
What layers form the medulla of the embryonic gonad?
|
- Rete cords (inner most)
- Primary sex cords (middle - Tunica Albugenia (outer most) |
|
|
What layers form the cortex of the embryonic gonad?
|
- Germinal epithelium
|
|
|
In the formation of the gonads, what is derived from endoderm of archentron? What does it do?
|
Primoridal Germ Cells - forms gametes
|
|
|
What is the name of the edge of the coelom will end up encasing the gonad?
|
Germinal epithelium of genital ridge
|
|
|
What structures are important in the indifferent gonad?
|
- Primordial germ cells
- Primary Sex cord (sticks out) |
|
|
When the indifferent gonad distinguishes itself as either to become a testes or an overy, what happens?
|
- Testes - primary sex cords predominate (they make sperm)
- Ovaries - primary sex cords disappear |
|
|
What structure makes sperms in the testes?
|
Primary Sex Cords
|
|
|
What structure makes eggs in the ovaries?
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Secondary Sex Cords
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In the development of the testes, what happens after the primary sex cords show domination?
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Seminiferous tubules carry sperm to epididymus
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In the development of the ovary, what happens after the primary sex cords disappear?
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All connections to tubules of sexual kidney are lost
- Ovarian follicles go into coelom (not homolog to primary external) |
