Brain Development and Neuronal Genesis

These flashcards cover key concepts of brain development, neuron genesis, and the distinct processes involved in neuronal migration and differentiation.

What are the stages involved in the genesis of neurons?

Cell Proliferation, Cell migration, and Cell differentiation.

What forms the central nervous system (CNS)?

The CNS forms from the walls of a fluid-filled neural tube.

What is the role of radial glial cells in brain development?

Radial glial cells provide a scaffold for cortical development and help guide neuroblasts.

What key protein is important for neuronal migration?

Reelin (RELN) is important for neuronal migration.

What do the terms 'chemoattractant' and 'chemorepellent' refer to?

Chemoattractant is a cue that attracts axons, whereas chemorepellent is a cue that repels axons.

What is Roger Sperry's chemoaffinity hypothesis?

It states that neurons connect with targets based on interactions with specific molecular markers.

What distinguishes the formation of excitatory and inhibitory neurons?

Excitatory pyramidal neurons originate from different precursor cells and migrate radially, while inhibitory interneurons arise from regions such as the medial ganglionic eminence.

Why do CNS axons not regenerate after injury in higher mammals?

CNS myelin is inhibitory to neurite outgrowth, containing factors like MAG and Nogo-A that prevent regeneration.