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This activity has two parts. In part A students stretch blood vessels (a piece of artery and a piece of vein) and measure how elastic they are. In part B they look at the histology of the blood vessels using a microscope.
Keywords: Arteries; Mechanical properties elasticity 1. Introduction It is well known that the elasticity of materials is expressed in Hooke’s law as follows: Tensile stress of a solid is proportional to the amount of deformation, provided the deformation is not permanent. Hooke’s law applied to an elastic bar of length l can be expressed ...
The elastic properties of the arteries are essential for blood flow. The pressure in the arteries increases and arterial walls stretch when the blood is pumped out of the heart. When the aortic valve shuts, the pressure in the arteries drops and the arterial walls relax to maintain the blood flow.
Part A: Elastic recoil in arteries and veins. Suspend a ring of artery from a hook on a clamp stand. Use a metre rule to record the length of the ring once the mass carrier has been attached to the free end of the ring. Attach a 10 g mass (see Figure 1) and record the length of the ring after the mass is added.
Elastic recoil in arteries and veins. Take rings of artery and vein tissue. Load and unload with 10 g masses and hence assess differences in elasticity. Consider how the elastic properties suit the different functions of artery and vein in the circulatory system.
21-1 Blood Vessels. The Tunica Intima (Inner Layer) Includes: The endothelial lining. Connective tissue layer. Internal elastic membrane. In arteries, is a layer of elastic fibers in outer margin of tunica intima.
A 20% increase in radius leads to a doubling in flow if all other variables are constant. Or, as another example, resistance is 16 times greater in a coronary artery with a diameter of 2 mm (e.g., a distal obtuse marginal) than in a coronary artery with a diameter of 4 mm (e.g., the proximal left anterior descending).
