Health

Human Blood :

Human blood is grouped into four types: A, B, AB, and O. Each letter refers to a kind of antigen, or protein, on the 

surface of red blood cells. For example, the surface of red blood cells in Type A blood has antigens known as 

A-antigens.

Blood Group System

Group A – has only the A antigen on red cells (and B antibody in the plasma)

Group B – has only the B antigen on red cells (and A antibody in the plasma)

Group AB – has both A and B antigens on red cells (but neither A nor B antibody in the plasma)

Group O – has neither A nor B antigens on red cells (but both A and B antibody are in the plasma)

There are very specific ways in which blood types must be matched for a safe transfusion:

Type O– blood is considered the “universal donor” because it can be donated to people of any blood type. Type 

AB+ blood is considered the “universal recipient” because people with this type can receive any blood type.

Blood Types and the Population

	Caucasians	African American	Hispanic	Asian
O +	37%	47%	53%	39%
O -	8%	4%	4%	1%
A +	33%	24%	29%	27%
A -	7%	2%	2%	0.5%
B +	9%	18%	9%	25%
B -	2%	1%	1%	0.4%
AB +	3%	4%	2%	7%
AB -	1%	0.3%	0.2%	0.1%

Blood Pressure Explained

Blood pressure is the force of blood against the walls of arteries. Blood pressure is recorded as two numbers—the systolic pressure (as the heart beats) over the diastolic pressure (as the heart relaxes between beats). The measurement is written one above or before the other, with the systolic number on top and the diastolic number on the bottom. For example, a blood pressure measurement of 120/80 mm Hg (millimeters of mercury) is expressed verbally as “120 over 80.”

Normal blood pressure is less than 120 mm Hg systolic and less than 80 mm Hg diastolic.

When systolic and diastolic blood pressures fall into different categories, the higher category should be used to classify blood pressure level. For example, 160/80 mm Hg would be stage 2 hypertension (high blood pressure).

	Blood pressure level (mm Hg)
Category	Systolic	Diastolic
Normal	< 120	< 80
Prehypertension	120–139	80–89
High blood pressure
Stage 1 hypertension	140–159	90–99
Stage 2 hypertension	>=160	>=100

NOTE: < means less than; 

             >= means greater than or equal to. 

Do you know ?

- Blood makes up about 7 percent of your body's weight.

- There is no substitute for human blood.

- A newborn baby has about one cup of blood in his body.

- Anyone in good health, at least 17 years old, and at least 110 pounds may donate blood every 56 days, or every 

  two months.

- Each year more than 4.5 million lives are saved by blood transfusions.

- About one in five people admitted to the hospital will need blood.

- Up to three: the number of patient that can be treated with one pint of donated blood.

- 50 percent of the U.S. population is eligible to donate blood -- only 5 percent do.

- Cancer, trauma patients, and those undergoing open-heart surgery require platelet transfusions to survive.

- The actual blood donation usually takes less than 15 minutes. The entire process -- from the time you sign 

   in to the time you leave -- takes about an hour.

- Donors must be 17 years of age or older and weigh at least 110 pounds.

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Real facts about Human Brain :

- Average brain width = 140 mm

- Average brain length = 167 mm

- Average brain height = 93 mm

- The average spinal cord is 45 cm long in men and           43 cm long in women.The spinal cord weighs appro                          x.35 grams.

- The human brain weighs on average three pounds, or 1.5 kg.

- The human brain is about the size of a cantaloupe.

- Nerve impulses to and from the brain travel as fast as 170 miles per hour.

- The brain operates on the same amount of power as 10-watt light bulb.

- The human brain cell can hold 5 times as much information as the Encyclopedia Britannica.

- Your brain uses 20% of the oxygen that enters your bloodstream.

- The brain is much more active at night than during the day.

- Neurons (nerve cell) continue to grow throughout human life.

- The brain itself cannot feel pain.

- 80% of the brain is water.

- Approximately 20% of the blood flowing from the heart is pumped to the brain.

- The human brain can be divided into  three main parts: forebrain, midbrain, and hindbrain.

- The brain has a processing capacity of 0.1 quadrillion instructions per second.

- The Hypothalamus part of the brain regulates body temperture much like a thermostat.

- Babies are born with around a 100 billion brain cells.

- The human brain contains around 400 miles of blood vessels.

- The left side of your brain (left hemisphere) controls the right side of your body; and, the right side of your brain (right hemisphere) controls the left side of your body.

- You will lose consciousness in 10 seconds after the loss of blood supply to the brain.

- While dreaming brain also refreshes stored memories, deciding which ones to keep and which not.

- The human brain is the fattest organ in the body and may consists of at least 60% fat.

- Neurons develop at the rate of 250,000 neurons per minute during early pregnancy.

- Alcohol interferes with brain processes by weakening connections between neurons.