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Name 11 derivatives of neural crest cells

PNS c.; Pseudounipolar ganglion c. of spin. and cran. nerve ganglia; Schwann c.; Multipolar ganglion c.; Leptomeninges; Chromaffin c.; Melanocytes; Odontoblasts; Aorticopulm. septum of heart; Parrifollicular c.; Skeletal/connective tissue of phar. arches

Give rise to peripheral nerves and sensory and autonomic ganglia

Peripheral nervous system cells

Give rise to myelin sheath

Schwann cells

Related to autonomic ganglia

Multipolar ganglion cells

Give rise to pia and arachnoid around brain and spinal cord

Leptomeninges

Give rise to epinephrine in the suprarenal medulla

Chromaffin cells

Pigment cells

Melanocytes

Give rise to predentin

Odontoblasts

Calcitonin -producing C-cells

Parrifollicular cells

Name the parts of the three-vesicle stage

Prosencephalon, Mesencephalon, Rhombencephalon

What do the three vesicles of the three-vesicle stage differentiate into?

Prosencephalon (rostral) → Telencephalon

What does the Telencephalon differentiate into?

Telencephalon (dorsal) → Cerebral cortex and hippocampus

What does the Mesencephalon differentiate into?

Cerebral aqueduct

What does the Diencephalon differentiate into?

Diencephalon → Basal ganglia → Basal forebrain, olfactory bulbs caudal thalamus, hypothalamus, optic cups

What does the Metencephalon differentiate into?

Cerebellum and pons

What does the Myelencephalon differentiate into?

Medulla

What are BMPs and how are they used?

Bone Morphogenic Proteins. They are soluble protein ligands that bind to bone morphogenic protein receptors (BMPRs) and release transcription factors into the nucleus for development of ectodermal cells.

What are two important regulators in nervous tissue development and describe their function?

Noggin and Chordin.These are BMP antagonists and block BMPs from binding to BMPRs. High concentrations of Noggin and Chordin are released near BMPRs and bind a sufficient amount of receptors allowing cells to develop into nervous tissue (default).

How is shaping of the neural tube accomplished?

Shaping of the neural tube is accomplished using cadhedrins, which are the self binding proteins that allow cells to clump together.

When is the Neuronal birthdate?

When a cell divides for the last time, leaves the ventricle, and migrates to its appropriate location

Abnormal islands or clusters of cells, usually in the cortex

Heterotopias

Which cells of the Hippocampus are being developed postnatally?

cells in the subventricular zone-->granule cells of the dentate gyrus

Which cells of the Cerebellum are being developed postnatally?

rhombic lip, lateral migration of cerebellar granule cells

Which cells of the Thalamus are being developed postnatally?

ganglionic eminence, rhombic lip equivalent for some thalamic neurons

Segmentation and regionalization of neuromeres (giving rise to forebrain structures) and rhombomeres (giving rise to hindbrain structures) are coded by ___________ ____________

Intrinsic Factors

Which genes specify the anterior-posterior axis and segment identity of hindbrain structures during early embryonic development?

Hox genes

Which genes specify the anterior-posterior axis and segment identity of forebrain structures during early embryonic development?

Ox1, Ox2, Pax genes.

What is a group of cells located near the posterior edge of the neural tube of the developing embryo?

Hensen's node

Where does the Anterior/Posterior difference in specification come from?

Low (hindbrain) and high (forebrain) affinity receptors to Retinoic Acid (RA) at certain areas.

What is comprised of a group of cells located at the ventral aspect of the neural tube?

The floorplate.

What types of SHH receptors form which types of neurons?

Low-affinity receptors for SHH are activated ventrally (in the basal floorplate) to form motor neurons while high-affinity receptors (in the alar floorplate) are activated by SHH to form somatosensory neurons

What type of neural tube closure failure occurs when retinoic acid is over-secreted? undersecreted?

Anencephaly. Spina bifida.

Name 3 ways axons find their way to make proper connections.

• Axon path finding: using growth cones as guides

The tips of growing axons have_________ ________, which stick out and explore the extracellular environment

growth cones

Growth cones possess fine processes called __________, which rapidly form and disappear as they sense the environment

Filopodia

What do you call the axon that everybody follows because it developed in the correct direction?

Guidepost cell

What axon guidance molecules are transmembrane or membrane-associated and signal via Eph Receptors (Receptor Tyrosine Kinases)?

Ephrins

What axon guidance molecules are primarily repulsive cues that can either be bound to the cell surface or secreted?

Semaphorins

What do you follow want to follow basal lamina?

Integrins

What do you follow if you want to follow oligodendrocytes (glial cell direction)?

Ng-CAMs

What do you follow if you want to follow an axon pathway that is already existing in the body (neural cell direction)?

N-CAM

When do we have Polyneuronal Innervation?

In early development.

What protein do motor neurons release that embeds in the basal lamina or synaptic cleft and that allows Ach receptors to aggregate and come together in one spot near the synapse, anchoring them there, and promoting point to point elegance of the NMJ?

Agrin

What mediates apoptosis?

Neurotrophins

What are the three types of regeneration or repair in the adult nervous system?

Regrowth of severed peripheral axons, local sprouting or longer extension of axons and dendrites at sites of traumatic damage, and ongoing generation of new neurons in the brain.

Trace the signal flow in the sensory system

external world -> sensory receptors -> spinal cord -> thalamus -> cerebral cortex

What are the two components that encode the magnitude of a stimulus?

Frequency of APs within a single axon and number of axons activated

What are the two types of adaptation receptors?

Phasic (rapid) and tonic (slow)

Spinal cord grey matter is divided into 9 different...

...Rexed's laminae

Dorsal and ventral horns on each side are connected to each other by...

...Spinal Cord Commissure

How is the anterolateral system organized?

Contralaterally

How are the dorsal column pathways organized?

Ipsilaterally

In Brown-Sequard Syndrome, which side has loss of pain and which has loss of touch and pressure perception?

• Ipsilateral loss of touch, pressure perception below the level of the lesion.

In Syringomyelia, what kind of loss of sensation do you get?

Loss of pain and temperature sensation on both sides

What do the two posterior spinal arteries supply?

The dorsal 1/3 of the spinal cord

What do the embryological ventral and dorsal thalamus become?

The thalamus as we know it today is all embryologically Dorsal thalamus.The Thalamic Reticular Nucleus (sheet surrounding the thalamus) is an embryological derivative of the ventral thalamus.

What nucleus in the thalamus is responsible for somatosensation of the head?

Ventral Posterior Medial (VPM)

What nucleus in the thalamus is responsible for somatosensation of the body?

Ventral Posterior Lateral (VPL)

What nucleus in the thalamus is responsible for olfaction?

Medial Dorsal

What nucleus in the thalamus is responsible for vision?

Lateral Geniculate Nucleus (LGN)

What nucleus in the thalamus is responsible for audition?

Medial Geniculate Nucleus (MGN)

What are the 2 ways in which nuclei of the thalamus project to the cerebral cortex?

Dense Projections (specific; goes to layer 4 and 6) and Diffuse Projections (diffuse; goes to layer 1)