Tuesday, November 20, 2007
The Human Heart
The heart is essentially a muscle(a little larger than the fist). Like any other muscle in the human body, it contracts and expands. Unlike skeletal muscles, however, the heart works on the "All -or-Nothing Law". That is, each time the heart contracts it does so with all its force. In skeletal muscles, the principle of "gradation" is present. The pumping of the heart is called the Cardiac Cycle, which occurs about 72 times per minute. This means that each cycle lasts about eight-tenths of a second. During this cycle the entire heart actually rests for about four-tenths of a second.
Make-up of the Heart.
The walls of the heart are made up of three layers, while the cavity is divided into four parts. There are two upper chambers, called the right and left atria, and two lower chambers, called the right and left ventricles. The Right Atrium, as it is called, receives blood from the upper and lower body through the superior vena cava and the inferior vena cava, respectively, and from the heart muscle itself through the coronary sinus. The right atrium is the larger of the two atria, having very thin walls. The right atrium opens into the right ventricle through the right atrioventicular valve(tricuspid), which only allows the blood to flow from the atria into the ventricle, but not in the reverse direction. The right ventricle pumps the blood to the lungs to be reoxygenated. The left atrium receives blood from the lungs via the four pulmonary veins. It is smaller than the right atrium, but has thicker walls. The valve between the left atrium and the left ventricle, the left atrioventicular valve(bicuspid), is smaller than the tricuspid. It opens into the left ventricle and again is a one way valve. The left ventricle pumps the blood throughout the body. It is the Aorta, the largest artery in the body, which originates from the left ventricle.
The Heart works as a pump moving blood around in our bodies to nourish every cell. Used blood, that is blood that has already been to the cells and has given up its nutrients to them, is drawn from the body by the right half of the heart, and then sent to the lungs to be reoxygenated. Blood that has been reoxygenated by the lungs is drawn into the left side of the heart and then pumped into the blood stream. It is the atria that draw the blood from the lungs and body, and the ventricles that pump it to the lungs and body. The output of each ventricle per beat is about 70 ml, or about 2 tablespoons. In a trained athlete this amount is about double. With the average heart rate of 72 beats per minute the heart will pump about 5 litres per ventricle, or about 10 litres total per minute. This is called the cardiac output. In a trained athlete the total cardiac output is about 20 litres. If we multiply the normal, non-athlete output by the average age of 70 years, we see that the cardiac output of the average human heart over a life time would be about 1 million litres, or about 250,000 gallons(US)!
Reference: www.google.com
Saturday, November 10, 2007
The Taurus
Taurus is an astrological sign which originated from the constellation Taurus, and is the second sign of the zodiac. Taurus is classed as a negative or feminine, introverted, sign; its Element is Earth and its Quality is fixed. Traditionally in astrology Taurus is ruled by the planet Venus. The opposite sign to Taurus is Scorpio. Under the tropical zodiac, Taurus is occupied by the Sun from April 20 to May 20. In house(astrology) the 2nd House is the house the Taurean rules, in the 2nd House dates are occupied on July 23 to August 7. The glyph is the alchemical symbol for rocksalt. In astrology the astrological signs represent twelve equal segments or divisions of the zodiac . According to astrological beliefs, celestial phenomena reflect or govern human activity on the principle as "as above, as below", so that the twelve signs at the same time are held to represent twelve basic personality types or characteristic modes of expression. The scientific community generally considers astrology as a pseudoscience or superstatios.; yet despite this, belief in astrology remains widespread.
Reference: www.google.com
Saturday, November 3, 2007
Cast you burden to the Lord, he wil sustain you
We believers in Christ do not have to stage elaborate rituals to escape our worries for brief time. What we have to do is to offer those worries to the Lord and He will sustain us.
By ourselves, we can do nothing. we greatly need our savior's hand to aid us in this journey towards a blissful eternity. Let us cast our burden to the Lord for surely he shal sustain us. "My yoke is sweet and my burden is light," Jesus once said. Problems cast to him will be borne light and with merits for eternal life.
Jesus my sabior, my refuse and hope, all my cares, my worries nad anxieties will be cast into your feet. In all my problems. I will be the Simeon of Cyrene who had helped you carry the cross while the way to Mt. Calvary. You have taken the heaviest part of them. Lord, remember by myself, i can do nothing, but with you, I can do everything. Lord, into your hands I commend all these things. Amen