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The major body fluid which acts as the lifeline of the living organisms is "Blood". Blood is an extremely complex biological fluid. It consists of blood cells suspended in plasma and other different types of cells which include white blood cells, platelets etc. The blood flow in arteries and veins are closely linked to the blood vessel properties.
Compared to the lungs' apex, the ventilation rate is 50% greater at the base. The V/Q ratio in the apex is roughly 3.3 and 0.63 in the base, which indicates that perfusion is greater than ventilation towards the base, and the ventilation rate is greater than perfusion towards the apex. [3]
A flow that is not a function of time is called steady flow. Steady-state flow refers to the condition where the fluid properties at a point in the system do not change over time. Time dependent flow is known as unsteady (also called transient [8]). Whether a particular flow is steady or unsteady, can depend on the chosen frame of reference.
Turbulent flow is defined as the flow in which the system's inertial forces are dominant over the viscous forces. This phenomenon is described by Reynolds number, a unit-less number used to determine when turbulent flow will occur. Conceptually, the Reynolds number is the ratio between inertial forces and viscous forces.
The apex beat may also be displaced by other conditions: Pleural or pulmonary diseases; Deformities of the chest wall or the thoracic vertebrae; Sometimes, the apex beat may not be palpable, either due to a thick chest wall, or conditions where the stroke volume is reduced; such as during ventricular tachycardia or shock.
Regurgitation is blood flow in the opposite direction from normal, as the backward flowing of blood into the heart or between heart chambers. It is the circulatory equivalent of backflow in engineered systems. It is sometimes called reflux.
Skeletal muscle pump: Rhythmical contractions of limb muscles as occurs during normal activity such as walking, running, and swimming, promotes venous return.; Decreased venous capacitance: Sympathetic activation of veins decreases venous compliance, increases vasomotor tone, increases central venous pressure and promotes venous return indirectly by augmenting cardiac output through the Frank ...
Given the proposed manner of action of the muscle pump to increase arterial blood flow, it would seem impossible for a muscle contraction and skeletal muscle hyperemia to be uncoupled. Another experiment recently was only able to find evidence that vasodilation , not the skeletal muscle pump, was responsible for maintaining proper pressure and ...