Anatomy Flashcards
how many cranial and spinal nerves
12 pairs of cranial
31 pairs of spinal
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
how does the brain form
from the neural tube
at 4 weeks forms primary vesicles (pros, mes and rhomb -encephalons)
at 6-8 week form secondary vesicles
what does the telecephalon form
cerebral hemispheres
what does the diencephalon form
thalamus, hypothalamus
what does the mesencephalon form
midbrain
what does the metencephalon form
pons, cerebellum
what does the myelencephalon form
medulla oblongata
what makes up the brainstem
mid brain
pons
medulla oblongata
what makes up the diencephalon
thalamus + hypothalamus
what are the majority of neurones
multipolar with many dendrites and one axon
what is the soma of a neurone
contains the nucleus and cellular apparatus
what way is electric activity going in an axon
away from the cell body
what do glial cell do
support cells for CNS
what are the 4 types of glial cells
astrocytes, oligodendrocytes, microglia, ependymal cells
what do astrocytes do
support, maintain BBB, environment homeostasis
star shaped
what is the role of the BBB
prevents things in blood directly accessing parenchyma of the brain
is there connective tissue in the CNS
no- why you need glial cells
what is the role of oligodendrocytes
produce myelin in the CNS (not in PNS) (wrap cell membranes around axons to increase the speed of conduction)
what is the node of ranvier
a gap between two myelinated axon areas- APs skip from one node to the next
what is the role of microglia
(hemopoietic (bone marrow) origin)
immune monitoring and antigen presentation (when activates take on appearance of macrophages)
what are ependymal cells
ciliated cuboidal/ culomnar epithelium that line the ventricles
what is a gyrus, sulcus and fissure
gyrus- ridge in cerebral cortex
sulcus- groove in cerebral cortex
fissure- deeper than gyrus
what fissures does the brain have
lateral (2) and longitudinal
what is grey matter
has lots of neurones, cell processes, synapses and support cells
(forms outside of brain)