Which planet could melt metal?

Most people think that Mercury is the hottest planet because it is nearest to the Sun. However, Venus, the second nearest planet, is the hottest because it has an atmosphere. Its atmosphere is primarily composed of carbon dioxide, which acts like a greenhouse.

The solar heat enters Venus’s atmosphere, but it cannot leave, heating the planet’s surface to about 900 degrees Fahrenheit (482 degrees Celsius). This temperature is hot enough to melt several metals, including lead, tin, and zinc.

How are carats and carob seeds related?

The weight of a carat (200 milligrams), the standard unit of measurement for gemstones, is based on the weight of the carob seed, which was once used as a weighing standard by jewelers in Africa and the Middle East. Historians believe the word “carat” is derived from an Arabic word meaning “bean” or “seed.”

Posted on Categories General

What causes hiccups?

A hiccup is a noise that your body makes when your diaphragm, the muscle barrier between your stomach and lungs, gets irritated and has spasms. The “hic” part of the sound is caused when air is sucked into your lungs, and the “cup” part of the sound happens when a special flap called the epiglottis, located between your tongue and vocal cords, slams closed over your windpipe.

Your diaphragm can become irritated from eating too much food, which causes an enlarged stomach to press against the wall of the muscle. Your diaphragm can also become irritated from lifting a heavy object or from breathing in too much air, which affects your normal breathing pattern. Hiccups may last a minute or two, but generally go away with time. Holding your breath, drinking a glass of water, or having someone scare you generally does not work to get rid of hiccups, since your diaphragm needs time to relax again.

Posted on Categories Health

Can farm animals be cloned?

Yes. In 1997 a team of scientists at the Roslin Institute in Edinburgh, Scotland, announced the birth of Dolly the sheep, the first clone (identical copy) of an adult mammal. The process used to create Dolly, called somatic cell nuclear transfer, began with an egg cell from one sheep. The scientists destroyed that egg cell’s nucleus and then injected the nucleus from the cell of another sheep into the egg cell. With a little encouragement from electronic stimulation, the donated nucleus fused with the egg cell, and the new cell began to divide.

The cluster of cells was then implanted into the uterus of the sheep that had provided the egg cell, and five months later Dolly was born—an exact replica not of the sheep that had carried her in the womb but of the sheep that had supplied the nucleus. While cloning mammals is very controversial, some scientists argue that cloning farm animals has advantages to livestock farmers, who could use the technology to breed only highquality animals that produce the most milk or the finest wool.

Why is “until the cows come home” considered a long time?

If left to their own devices, cows in pasture will regularly show up at the barn for milking twice a day: once in the morning and once in the evening. The expression “’til the cows come home” first appeared in the sixteenth century when most people were familiar with the cycles of farm life. It was often used when a party went on long into the night — it would have to end in the morning when the cows came home and needed milking.

Is it true that at one time there was no oxygen?

Oxygen is necessary for all humans, animals, and plant life to survive. When Earth was first formed, its atmosphere had no oxygen—the colorless, odorless and tasteless gas that makes up about 20 percent of the air we breathe. It had only a deadly combination of hydrogen, methane, ammonia, and hydrogen cyanide.

The hydrogen escaped into space and ultraviolet radiation from the Sun broke down the mixture, leaving only nitrogen and carbon dioxide. Only when life began and photosynthesis (the conversion of light energy into chemical energy by living organisms) occurred did oxygen first appear—about 3.4 billion years ago.

Why do birds often crash into windows?

Birds don’t see the way mammals do, and a reflection in a window might look like another bird. Most birds that are active during the day have eyes on either side of their heads, which gives them a wide field of view but little depth perception. In the springtime, many birds are territorial and when they establish territories they become aggressive and chase off intruders. Unfortunately, they don’t distinguish between their own reflection in a window (or car mirror) and they try to chase that reflection off. People sometimes add awnings and window screens to eliminate the reflection and stop birds from colliding into their homes or office buildings. Although a bird can crash into glass at any time, the behavior is seen less often when nesting season begins.