important role is to regulate the movement of materials into and out of cells. The phospholipid bilayer structure (fluid mosaic model) with specific membrane. proteins accounts for the selective permeability of the membrane and passive. and active transport mechanisms.
Structure of Blood Vessels a) Three distinct layers or tunics form the walls of blood vessels: ---The tunica interna (tunica intima) is the innermost layer.It contains the endothelium which is a continuation of the endocardial lining of the heart.tructure of Blood Vessels a) Three distinct layers or tunics form the walls of blood vessels: ---The tunica interna (tunica intima) is the innermost layer.
The layer of the digestive tract that contains blood and lymph  vessels and nerve cells is the sub mucosa.The sub mucosa layer is  located underneath the mucosa layer. Edit. Share to: Judy Olmsted. 78,944 Contributions. Taught College level A&P for 27 years. Biology Supervisor.he Dermis contains 2 main layers (plexi) of blood vessels, which can be referred to as the superficial de â¦ rmal plexus and deep dermal plexus. More detail: The dermis can be split up into two layers, the papillary dermis and reticular dermis. One vascular plexus is situated in each.