Wednesday, December 08, 2010

Why does Labor Begin?



What starts labor is one of the great mysteries of medicine. "That's a Nobel prize-winning question," says Dr. Mark Taslimi, a professor of obstetrics and gynecology at Lucille Packard Children's Hospital in Palo Alto, California.

One current theory is that stress hormones are released from the adrenal gland of the baby, which creates chemical changes in the placenta that cause the muscle of the uterus to develop involuntary contractions that turn into labor, he says. These regular, frequent contractions and the resulting opening of the cervix signal that labor has begun..




Tuesday, November 09, 2010

Why Dogs Turn Around Three Times Before Lying Down?

According to American humorist Robert Benchley, a dog teaches a boy three things: fidelity, perseverance, and to turn around three times before lying down.

If you've ever wondered why dogs turn around several times before flopping down on the floor, the answer is simple genetics. They've been genetically programmed to trample their sleeping areas in the wild so that the grass is tamped down to make a comfortable resting place.

Although your dog have the finest dog bed money can buy, he still feels the urge to circle before lying down, even in the comfort of the modern home. It's nature at work. Nature is the reason dogs gobble their food. The most successful survivors were able to eat fast before other members of the pack could grab a share. Wild dog cousins didn't know when his next meal would come, so being the fastest gorger was a real advantage.

Tuesday, October 19, 2010

Why Does Lightning Flash?


An example of a single lightning flash making contact with the ground in 2 different places. Photo: Copyright Steve Hodanish.
As the atmosphere heats and cools. It expands and contracts, causing changes in pressure and air movement. Water droplets inside clouds have a positive electrical charge at the top of the cloud and a negative charge at the bottom.
When the negative charge comes near enough to an attracting positive charge on the Earth below or on another cloud, the electrical energy is released in a flash of light. There may also be a loud bang, called thunder, at the same time. This is caused by the air being heated to a tremendous temperature, and the explosive noise is when it expands suddenly.
However, as light travels faster through the air than sound, we see the lightning flash before hearing the thunder.
FACT:
Magnetic energy produced by vast storms on the Sun’s surface strikes the upper atmosphere of the Earth, producing patterns in the sky near the poles called the Northern Lights or aurora borealis.

Tuesday, September 14, 2010

Why do onions make you cry?



Onions are made of cells just like other plants. The cells are divided into two sections separated by a membrane.One side of the membrane contains an enzyme which helps chemical processes occur in your body. The other side of the membrane contains molecules that contain sulfur.The contents on each side of the membrane when you cut an onion will mix and cause a chemical reaction. This will produce molecules such as ethylsufine which make your eyes water.



To prevent crying when you cut an onion;
  • Cut it under a running tap of cold water.

"The sulfur compounds dissolve in water and are rinsed down the sink before they reach your eyes."
  • You can also put the onion in the freezer for ten minutes before you cut it.

"Cold temperatures slow down the reaction between the enzyme and the sulfur compounds so fewer of the burning molecules will reach your eyes."

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