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Understanding
the Circulatory System
The
role of the circulatory system is twofold: It delivers oxygen and
nutrients to all parts of the body while picking up waste materials and
toxins that need to be eliminated. It accomplishes this monumental
task through a network of nearly 60,000 miles of blood vessels and a
fist-sized organ, the heart, which pumps More than 2,000 gallons of blood
through its chambers each day.
Transporting your life blood
Blood vessels are divided into three main categories: arteries, veins and
capillaries. Arteries are thick-walled vessels that carry blood
from the heart to all parts of the body. Each time a person's heart
beats, the elastic walls of the arteries swell to make room for the blood
that is forced into them. The muscles inside the walls contract
slowly, in effect squeezing the blood and forcing it to move along the
arteries toward the capillaries.
If arteries loose their elasticity, known as arteriosclerosis
(hardening of the arteries) the heart has to work much harder to keep the
blood circulating. Like a machine, if the heart is overworked and
not properly maintained, it cannot function optimally.
The lymphatic system
In addition to
moving the blood along, the squeezing process forces fat globules, tiny
protein particles and other nutrients to 90 outside of vessel
walls. Once these things are out, due to their size, they cannot
re-enter. Instead, they are collected along with other cellular'
debris lying between cells.
The lymphatic system picks up these particles and Mixes them with plasma,
which forms lymph. The lymph is then purified, recycled in the
lymph nodes, and added back to the blood. This process, which is
vital to the circulatory system, is also essential to the success of the
immune system.
The return trip
Veins are thin-walled blood vessels. Their purpose is to return the
blood from the body to the heart. Many larger veins have valves to
prevent a back-flow of blood. If these valves
experience prolonged or excessive pressure, veins can become
overstretched, and the valves may be destroyed or rendered incompetent.
This results in problems like varicose veins.
Capillaries are the smallest blood vessels in the body. They serve
as intermediaries, connecting arteries with veins. Since capillaries
are extremely small and have permeable walls, it's possible for
capillaries to reach nearly every cell in the body and to transfer
substances, including important nutrients, to and from the tissues.
The Heart
The heart is made up primarily of muscles that facilitate its pumping
action. This most vital of organs consists of four compartments or
chambers. The Upper two are referred to as the atria, and the lower
two as ventricles. Oxygen-poor blood enters the right atrium and
moves through it to the right ventricle. From there blood is sent
via the pulmonary arteries to the lungs so that it can pick up a fresh
supply of oxygen. Once it has taken on a supply of oxygen, blood
moves through the Pulmonary veins first to the left atrium, and then to
the left ventricle. The heartbeat is sustained by the sinoatrial (SA) node, which functions as a
pacemaker. A healthy heart has a regular beat, although the rate
can vary depending on several factors including age, sex, physical
activity and emotion.
Health factors
For the circulatory system to function properly,
the heart must be strong, the vessels capable of safely transporting
optimal amounts of blood and the blood itself must be healthy.
Serious problems can arise when these conditions are not met. Each
year approximately, 25 percent of all deaths in the U.S. occur from
heart attacks and the majority of these are attributable to hardening of
the arteries. In addition to heart attacks, a poor circulatory
system can lead to strokes, kidney disease, varicose veins, blood clots
and a variety of other conditions that can kill or severely limit the
enjoyment of life.
Three major factors that contribute to circulatory problems are
hypertension (high blood pressure), high levels of triglycerides and
cholesterol in the bloodstream and smoking. Nutrition has
been linked directly to hypertension and high levels of triglycerides and
cholesterol. Other factors include obesity, heredity and
emotional stress. Unfortunately, the threat of problems
increases significantly when more than one factor is present. That
means that when a person has three risk factors, his chances for disease
are six times greater than when only one is present.
How can you maintain a healthy circulatory system? Most
experts agree that the keys are to avoid smoking, monitor your diet,
exercise regularly and manage stress.
Copyright Nature’s Sunshine Products Inc
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