Central Nervous System Histology and Development PDF

Central Nervous System Histology and Development Lecture Learning Objectives 1. Visually identify components of the CNS in the histology slides 2. Trace the development of the neural tube as it forms the CNS, linking the three vesicles that develop in the thir...

Central Nervous System Histology and Development Lecture Learning Objectives 1. Visually identify components of the CNS in the histology slides 2. Trace the development of the neural tube as it forms the CNS, linking the three vesicles that develop in the third week to the six subdivisions of the brain and brainstem and the morphological changes that occur 3. Compare the basal and alar plates, linking them to the developed CNS and its components  LO1 Cerebrum Gray matter Neurons Nucleus Nucleolus White matter Myelinated axons  Neurons LO1 Cerebellum Cell body Gray matter White matter Nucleus Nucleolus Axon hillock  LO1 Spinal Cord Grey matter White matter Neurons Myelinated axons Nucleus Nucleolus  LO1 Neurons Cell body Nucleus Nucleolus Nissel substance Ganglion Axons/nerve fiber Myelin sheath  LO1 Nerves Axon/nerve fiber Myelin sheath  LO1 Nerves Fascicle Epineurium Perineurium Endoneurium  LO1 Nerves Axon/nerve fiber Myelin sheath Node of Ranvier/Neurofibril node Neurolemmocyte Nervous System Development  LO2 Development of the Nervous System Begins in 3rd week Neurulation- Notochord induces overlying ectoderm to differentiate into neural plate in trilaminar embryo, forms neural tube Neuroprogenitor cells of neural tube wall proliferate and form brain and spinal cord Neural tube differentiates to form CNS divisions Neural canal will form the ventricles and central canal Neural crest cells gives rise to the PNS and autonomic nervous system Before We Are Born, Moore et al. (2020)  LO2 Development of the Brain Week three→ Prosencephalon Mesencephalon Rhombencephalon Metencephalon Week 5 Telencephalon Adult structure Mesencephalon -Pons -Cerebrum Cerebral aqueduct -Cerebellum Rhom Pro -Lateral ventricles Fourth ventricle Met Tel Di My Diencephalon Myelencephalon -Epithalamus -Medulla oblongata -Talamus -Hypothalamus Fourth ventricle Third ventricle LO2  LO2 Development of the Brain Telencephalon grows rapidly, enveloping the diencephalon Folding begins embryological, especially in telencephalon Most sulci and gyri develop late in fetal development, formed at birth  LO3 Development of the Spinal Cord A. Neural tube is created via neurulation Rostral and caudal neuropores close B. Neuroprogenitor differentiate into neuroblasts and proliferate A B C. Alar plate→ posterior horn Remaining neural crest cells will form dorsal root ganglion with sensory neuron cell bodies within; axons grow out to form dorsal root D. Basal plates→ anterior horn Contain motor neuron cell bodies; axons will grow from neuronal cell bodies Neural canal becomes central canal C D Before We Are Born, Moore et al., 2020