The brain is a complex organ. It consists of gray matter (40%) and white matter (60%). The brain has three main parts: the cerebrum대뇌, the cerebellum소뇌, and the brain stem. The average weight of an adult human brain is about 1.3-1.4 kilograms. At bi
[호]
Red blood cells are sometimes simply called “red cells.” They are doing a very important job in your body. They travel through your body continuously, delivering oxygen and removing waste. A single drop of blood contains millions of red blood cells! Red
The sea appears to be blue most of the time. But the sea can be many other colors depending on particles in the water, the depth of the water, and the amount of skylight. The colors we see depend on the reflection of the visible wavelengths of light to ou
Today, glass is used to make many things. Windows, milk bottles, mirrors, doors for buildings, light bulbs, computer screens and many other things are made of glass. Glass is made by melting several minerals together at very high temperatures. Actually,
A nebula is a huge, diffuse cloud of gas and dust in space. The gas in nebulae is mostly hydrogen gas -- H2. Scientists believe that new stars form inside of nebulae. There are many kinds of nebulae such as Emission Nebulae, Reflection Nebulae, Planetar
here is not just one answer to this question. This is because not all fish have been tested for color vision. But according to scientists, the goldfish and many other fish can see in color. Color vision is the ability to see objects based not on how bri
Galaxies are huge collections of stars, dust and gas. They usually have several million to over a trillion stars. The distance across them is very great. And it can be several hundred thousand light years!
Stem cells are the body’s master cells. They are sometimes called “magic seeds.” This is because they are the basic building blocks of all tissues, organs and systems in the human body. Stem cells are special cells. They can turn into many different ce
Cats’ eyes glow in the dark. Also, many other animals that hunt at night have eyes that glow at night. So, why do their eyes appear to glow when a light shines on them? The glow that you see is light reflected from a mirror-like structure in their eyes.
If you look up in the sky, you can see beautiful clouds. Clouds form when water vapor condenses onto tiny dust particles floating in the air. The cloud formation happens when warm and cold air meet? when warm air rises up the side of a mountain and
[이전10개] 81 82 83 84 85 86 87 88 89 90 [다음10개]
