Flashcards in Nervous System Development I Pt II Deck (23):
Characteristics of the Isthmic Organizer
1. Located b/w Mesencephalon and the Metencephalon
2. It is a SIGNALING Center
3. Organizes and Polarizes Dorsal midbrain Midbrain and Cerebellum
What is the Principal Signaling molecule of the Isthmic Organizer?
What signaling molecules induce expression of En-1/2 and Pax-2/5?
Dorso-Ventral patterning of midbrain is primarily due to what?
SHH restricts the expression of what in Dorso-Ventral patterning?
What is the role of Pax-7?
Related to the formation of the ALAR plate
What is the role of Pax-6?
1. Expressed in Alar plate
2. “Master Gene” of EYE formation
3. Inhibits En-1 and Vice-Versa
- Results in the formation of the diencephalon and mesencephalon BORDER
The forebrain is segmented into what?
Characteristics of P1-P3
Defines the Diencephalon
Characteristics of P2-P3
Define the Dorsal/Ventral Thalamus
The Alar plate develops into what?
- Cerebral Cortex
- Basal Nuclei
- Optic Vesicles
Motor Axon Outgrowth
- Axons grow out from the motor neuroblast
(located in the basal plate of the spina cord)
What maintains the separation b/w CNS and PNS
- Created by Neural Crest Cells
Formation of a sensory neuron
- Cell bodies of sensory neurons are derived from Neural Crest Cells
(They form sensory spinal ganglia)
- Boundary caps maintain the separation
Cells bodies of sensory neurons form what?
Sensory Spinal Ganglia
Cues involved in Axon guidance
1. Caudal Half of somite
Role and Relationship of Pioneering Axon
The first axons to grow in a particular region
- Main fxn is laying down the initial growing path that subsequent growing axons
- NO anatomical difference b/w Pioneer and Follower axons
What happens when a Motor Axon meets a muscle fiber?
(Formation of NMJ)
1. Cessation of Outgrowth of Axon
2. Preparation by Neuron for release of NT molecules (ACh)
3. Muscle fiber preparation for signal transduction
What determines whether migrating neural crest cells differentiate into Autonomic neurons or other neural crest derivatives?
The sympathetic Pre-Ganglionic MN arise from what?
Intermediate Lateral Horns of Gray matter
T/F: Sympathetic POST-Ganglionic MN are myelinated.
- They are NOT Myelinated
The Parasympathetic Pre-Ganglionic MN are associated with what kinds of nerves?
- 3, 7, 9, and 10