the disk in the fundus of the eye marking the point at which the optic nerve enters; it is accompanied by blood vessels, is oval, light in color and the blind spot of the retina.
ARTERIOLES. In arterioles, the tunica intima consists of a continuous endothelium and a very thin subendothelial layer. In addition, a thin, fenestrated internal elastic lamina is present in larger arterioles but absent in terminal arterioles. Generally, the tunica media consists of 2 layers of smooth muscle cells.
Parts of the Muscles. Introduction to Parts of the muscles. Each muscle tissue is composed of muscle fibers that are further grouped into bundles of upto 150 fibers called âfasciculiâ. Each fasiculus is bordered by perimysium and fibers within each fasiculus are covered by endomysium.