Neuroanatomy Flashcards
Lecture 1
Cellular Neuroanatomy
What are the functions of neurones?
Proprioception. Responses to stimuli. Movement. Feeding. Senses. Balance. Blood pressure. Heart rate. Neurocrine.
What are the morphological types of neurones?
Unipolar. Pseudounipolar. Bipolar. Stellate. Pyramidal. Purkinje.
What are unipolar neurones?
Single process from soma. Ancestors of all neurons. Mainly in invertebrates.
What are pseudounipolar neurones? Give an example.
Single process split into 2. All sensory neurones. Ganglion cell of dorsal root
What are bipolar neurones? Give an example.
2 processes, one at each end. Mainly interneurones. Retinal bipolar cell.
What are multipolar neurones?
1 axon and many dendritic processes. Common in CNS.
Give an example of a stellate cell.
Motor neuron of CNS
Give an example of a Pyramidal cell.
Pyramidal cell of hippocampus.
Give an example of a Purkinje cell.
Purkinje cell of cerebellum.
What are the functions of glial cells?
Physical support. Separation. Myelination. NT scavenging. Potassium buffers in CNS. Removal of debris. Blood barrier function. Nutrition. Repair.
Which glia are responsible for nutrition?
Astrocytes
Which glia are responsible for repair?
Microglia
Where in a neuron do passive and active conduction occur?
Passive - Dendrites. Active - Axon.
What are the 3 embryological layers and their fates?
Ectoderm - Epidermis, PNS, CNS. Mesoderm - Muscles, Vascular System. Endoderm - Guts, Lungs, Liver.
Describe the process of neurulation.
Neural plate of the embryo’s dorsum invaginates, forming the neural groove, by the orders of the notochord. Neural groove pinches off forming the neural tube. The remaining neural crest cells migrate and form peripheral glia.
What are the possible committed progenitors of neural crest cells?
Melanocyte. Glial. Sensory. Sympatho-adrenal. Parasympathetic. Enteric.
What are the cell fates of Sympatho-adrenal progenitors?
Chromaffin cells. Small Intestine Epithelial cells. Sympathetic neurons.
What are the cell fates of Parasympathetic progenitors?
Cholinergic neurons.
What are the cell fates of enteric progenitors?
Peptidergic and serotonergic neurons.
What is cephalisation?
Centralisation of neural and sensory organs towards the anterior.
What are the vesicles of the 3-vesicle stage?
Proencephalon, Mesencephalon, Rhombencephalon.
What are the vesicles of the 5-vesicle stage?
Telencephalon, Diencephalon. Mesencephalon. Metencephalon, Myelencephalon.
What does the Telencephalon give rise to?
Cerebral cortex. Hippocampal formation. Basal ganglia. Amygdyla. Olfactory bulb.
What does the Diencephalon give rise to?
Thalamus. Subthalamus. Hypothalamus. Epithalamus. Optic nerve/tracts. Retinae.
What does the Mesencephalon give rise to?
Midbrain.
What does the Metencephalon give rise to?
Pons. Cerebellum.
What does the Myelencephalon give rise to?
Medulla.
What does the caudal part of the neural tube give rise to?
Spinal Cord
What are the 3 flexures present in the 5-vesicle embryo?
Cephalic, Cervical and Pontine.
What is the role of the cephalic flexure?
Divides the mesencephalon and the diencephalon.
What is the role of the cervical flexure?
Separates myelencephalon from spinal cord.
What is the role of the pontine flexure?
Separates metencephalon from the myelencephalon.
What are the 8 major structures of the mature brain?
Spinal Cord. Medulla. Pons. Cerebellum. Midbrain. Thalamus. Cerebral Cortex. Corpus Callosum.
What is the Cauda Equina?
Leash of nerves above coccyx. (L2-5; S1-5).
Why does the cauda equina not reach the bottom of the spinal cord?
Bone growth is faster than neural tube growth.
Lecture 2
Sensory Pathways
What are the main sensory fibre types?
A-alpha. A-beta. A-gamma. A-delta. B. C-DR. C-sympathetic.
Describe A-alpha fibres.
Motor/Proprioception. 100ms-1. Myelinated. 15um.
Describe A-beta fibres.
Touch/Pressure. 50ms-1. Myelinated. 7um.