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These form the ventricular system of the brain: [8] The neural stem cells of the developing brain, principally radial glial cells, line the developing ventricular system in a transient zone called the ventricular zone. [9] The prosencephalon divides into the telencephalon, which forms the cortex of the developed brain, and the diencephalon.
The area postrema is located in the caudal medulla oblongata near the junction of the brainstem and the spinal cord. [16] In humans and in most other mammals that have been studied, it consists of swellings on either wall of the fourth ventricle. [16] [17] In rodents and lagomorphs, however, the area postrema forms a midline structure dorsal to ...
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. [1] [2] It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek kardia meaning heart, and Latin vascula meaning vessels).
The circle of Willis (also called Willis' circle, loop of Willis, cerebral arterial circle, and Willis polygon) is a circulatory anastomosis that supplies blood to the brain and surrounding structures in reptiles, birds and mammals, including humans. [1] It is named after Thomas Willis (1621–1675), an English physician. [2]
The arachnoid mater makes arachnoid villi, small protrusions through the dura mater into the venous sinuses of the brain, which allow CSF to exit the subarachnoid space and enter the blood stream. Unlike the dura mater, which receives a rich vascular supply from numerous arteries, the arachnoid mater is avascular (lacking blood vessels).
A network of blood vessels travels to the brain and spinal cord by interlacing through the pia membrane. These capillaries are responsible for nourishing the brain. [8] This vascular membrane is held together by areolar tissue covered by mesothelial cells from the delicate strands of connective tissue called the arachnoid trabeculae.
This value is inversely related to the total cross-sectional area of the blood vessel and also differs per cross-section, because in normal condition the blood flow has laminar characteristics. For this reason, the blood flow velocity is the fastest in the middle of the vessel and slowest at the vessel wall.
The brain can regulate blood flow over a range of blood pressure values by vasoconstriction and vasodilation of the arteries. [ 56 ] High pressure receptors called baroreceptors in the walls of the aortic arch and carotid sinus (at the beginning of the internal carotid artery ) monitor the arterial blood pressure . [ 57 ]