更多"Did you ever wonder why you see the"的相关试题:
[单项选择]Did you ever wonder why you see the colors you do or if other animals see the same colors that you see We see light that bounces off of things around us. When the light enters our eyes, special cells tell our brains about the light. These cells are called photoreceptors. Light is made of little bits called photons. When the sun shines, trillions and trillions of these little bits of light fall on the earth. The photons bounce off of almost everything and some of them enter our eyes. Those bits that enter our eyes allow us to see. So, where does the color come from
Starting in the 1600s with Sir Isaac Newton, scientists have believed that there are different kinds of photons. Different types give rise to our sense of colors. The different photons are said to have different wavelengths. Sunlight contains all the different wavelengths of photons. The visible wavelength colors can be seen when you look at a rainbow. Raindrops acting as natural prisms produce the colors.
A. Red, white, and blue.
B. Red, green, and yellow.
C. Red, green, violet.
D. Red, green, blue.
[单项选择]Why do people shrinks
Did you ever see the movie Honey, I shrunk the kids It’’s about a wacky dad (who’’s also a scientist) who accidentally shrinks his kids with his homemade miniaturizing invention. Oops! (46)______
For older people, shrinking isn’t that dramatic or sudden at all. It takes place over years and may add up to only one inch or so off of their adult height ( maybe a little more, maybe less ) , and this kind of shrinking cant be magically reversed, although there are things that can be done to stop it or slow it down. (47)______
There are a few reasons. As people get older, they generally lose some muscle and fat from their bodies as part of the natural aging process. Gravity (the force that keeps your feet on the ground) take hold, and the bones in the spine, called vertebrae, may break down or degenerate, and start t collapse into one another. (48)______ But perhaps the most common reason why some older people shrink is because of osteoporosis.
Osteo