A tree loses water to the air by the process of transpiration at the rate of 110 g/h. This water is replaced by the upward flow of sap through vessels in the trunk. If the trunk contains 2000 vessels, each 100 μ m in diameter, what is the upward speed of the sap in each vessel? The density of tree sap is 1040 kg/m3.
Chapter 21- The Cardiovascular System: Blood Vessels and Hemodynamics Notes Blood Vessel Structure In general a blood vessel has 3 layers: 1. Tunica interna (aka tunica intima) - Innermost layer, adjacent to lumen - Endothelium - Basement membrane - Lamina propria (C.T. layer) - Internal elastic membrane. Fenestrated layer of elastic fibers 2. Tunica media - Middle layer, smooth muscle, and elastic fibers - Smooth muscle cells arranged circularly around the blood vessels - Vasoconstriction: smooth muscles contract, decrease in blood flow - Vasodilation: smooth muscles relax, increase in blood flow 3. Tunica externa