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What is Blood brain barrier is not present in - and explain in detail?
Ans. is 'c' i.e., Area postremao Certain areas of brain have fenestrated capillaries and because of their permeability, are said to be outside blood- brain barrier.o These areas are located around the third ventricle and are therefore called circumventricular organs,o These areas are:-Posterior pituitary (neurohypophysis) and the adjacent ventral part of median eminence of the hypothalamusThe area postremaThe organ vase ulusum of lamina terminalis (O VLT).o Although the blood-brain barrier is deficient in the circumventricular organs, the blood-CSF barrier in theseorgans is quite effective due to the presence of tight-junctions between the modified ependymal cells of the third ventricle called the 'tancytesV