Dendrite development Introduction - PICS Flashcards
What is the specification of dendrites based on?
Their 2D/3D shape
What does the shape of dendritic arbor of neurons tell you?
Need of connectivity of a neuron type e.g. if its selective, sampling, space filling
What are some methods you can employ to quantify the dendritic arbors?
Identifying branch orders as they increase whenever there’s a new branch point.
Or can measure the total dendritic length dendritic arbors and total number of dendritic points.
Count amount of different dendrites there are
What is sholl analysis?
Method of quantifying dendritic arbors. Draw concentric circles at specific distance from cell body and count how many times processes intersect those circles
What feature do 90% of excitatory neurons develop?
Spines on dendrites. But not these are NOT directly on dendrites
What does it mean if a dendrite is secile?
It is homogeneous and the whole thing contracts its spine
What does it mean if a dendrite is pedunculated?
Its spine has a head and neck
What are the steps in dendrite morphogenesis?
- Dendrites and axons are specified
- Dendrites extend away from the soma towards their target fields which is guided by attractive and repulsive guidance molecules
- Branching becomes necessary to cover the target field as dendrites reach further away from the soma. Intrinsic factors guide this process. This mainly occurs through interstitial branching.
- Dendrite growth is restrained when dendrites reach defined borders - tiling and self avoidance
- Dendrites differentiate and some develop spines
- Dendrite pruning refines the dendritic arbor and only those areas that make connections with axons and receive input would be established. External cues influence indirectly on intrinsic factors
What is interstital branching?
When a new branch comes from already established dendrite
