There is truly only one color.  Do you know which color is responsible for increasing the heart rate and respirations?
212191
ummmmmmmmmmmmmmmmmmmmm red
272458
the answer is "colors" \nolive and green are colors\nyou can't see the word colors, only what colors are\nand it has 6 letters in it.
18128
Taken from "Brain-Based Learning" written by Eric Jensen (Revised Edition, 2000)\n\nA recent study (Vuontela, et al. 1999) measured  the relative value of verbal cues versus color cues in learning and memory. In testing memory for verbs and memory for colors, learners better recalled color. And when objects were tested against color, once again, color memory was stronger. Even an intention to remember did not affect the outcome of the experiment.\n_______________\n\nTaken from "The Power of Color" by Morton Walker, 1991\n\n"Red - is an engaging and emotive color. Best for restaurants. It is considered more disturbing by anxious subjects, and more exciting to calm subjects. Triggers the pituitary and adrenal glands and releases adrenaline. May increase blood pressure and breathing, and stimulate appetite and sense of smell.\n\nYellow - is the first color a person distinguishes in the brain. Associated with stress, caution, and apprehension, yet it stimulates an overall sense of optimism, hope, and balance. Excellent for use in classrooms.\n\nOrange - has the characteristics halfway between red and yellow. It is one of the best colors for stimulating learning.\n\nBlue - is the most tranquilizing color. It calms tense subjects and increases feelings of well-being. When you see blue, your brain releases eleven neurotransmitters that relax the body, and may result in a reduction of temperature, perspiration, and appetite. Blue may be a bit too calming for most learning environments.\n\nGreen - is also a calming color. In response blood histamine levels may rise resulting in reduced sensitivity to food allergies. Antigens may be stimulated for overall better immune system healing.\n\nDark Colors - lower stress and increase feelings of peacefulness.\n\nBrown - promotes a sense of security, relaxation, and reduces fatigue.\n\nBright Colors - such as red, orange, and yellow spark energy and creativity. they can also increase aggressive and nervous behavior.\n\nGray - is the most neutral color.\n\nFor optimal learning, choose yellow, light orange, beige, or off-white. Those colors seem to stimulate positive feelings."\n\n__________________________________\n\nWhat this means in the educational environment.\nWe may be underutilizing the potential of color in the learning environment. Use color handouts and overhead transparencies. Conciously choose the colors you use in the classroom; hang colorful posters; and encourage the use of color in mind-maps, painting, projects, and posters.\n\n\nHope this helps some. \nLet me know if you need more
522474
normally blue because the oxygen diffuses blue light most.
640265
Color is actually made up.  We are seeing waves of light and our brain is interpreting them into what we perceive as colors.  Also, we see the waves of light that are being reflected off of things.  So if we see something as being blue that means that the other waves of "color" have been absorbed.  Quite interesting really, and a very good question.  Keep it up, I have had few good questions recently and was about to give up for the night.
633937
This is a question I've actually thought about before, but the problem is, there is no way to tell if everyone sees the same colors.\n\nFor example, I could be looking at a stop sign.  It is red.  I know what red looks like.  But what if another person had a different perspective of colors?  They are seeing, we'll say, what is green to me, but their whole life, people have called that color "Red," so they think it is red.  They have no way of knowing what red is to me, and vice versa.\n\nI'm sure there are some tests, but if you're just mixing up colors, it would be hard to tell.\n\nWhat a weird thought, huh?
614208
orange and lime green. if not that then lime green
82308
Yellow + Blue = Green\nBlue + Red = Purple\nRed + Yellow = Orange\n\n!!!!
258125
It's called synesthesia- Stimulation of one sense produces the sensation of another.\n\nI hadn't heard of colors=numbers, only music sparking color.\nOr colors =taste.  Very interesting.\n\nI remember hearing about this woman who sees colors when she plays music.  I'm guessing this is related. (see attached article- the very last one)
570975
Most cells are opaque, or colorless.  If you want a good view, you must color it.
423331
violet \nyou'll find it at the bottom of the color charts, last one
533177
sorry, I agree that D is correct. (\nhttp://www.abledata.com/abledata_docs/Night_Vision.htm )\n\nAs perception of white (or any gray levels) is the equal stimulation of all three different photopigments/photoreceptors, you can see all grey levels using your cones only. No mystery about it. If you understand additive color mixing you can use Photoshop to prove this on your computer. Or you can use colored transparencies and a projector. Research additive color mixing if you are not familar with it. So you can have no rods (look up night blindness) and still see black (no stimulation) and white (equal stimulation of all three cones) during the day time using your cones only. So the answer is no, you can not be "black, grey, white blind" , but it doesn't have to do anything with the presence or absence of rods in your eyes. \n\nThough there seems to be a really minor effect of rods on the perceived hue, colors could be somewhat less saturated,and it seems to rely on interaction of nerve cells other than the primary photoreceptor cell. Generally Pubmed or Google Scholar should both allow you to search large databases of science publications which haven't made it into textbooks.
14674
ah, i actually remember thinking that once... i always had a lot of questions like that, always so curious about stuff... that's why im a physics major, it explains so much... actually, while we may not be tasting or smelling the same thing, we are all seeing the same colors.  this is because each color has corrosponding wavelengths and frequencies of light on the electromagnetic spectrum.  Only a very small portion of this spectrum is even visible light, and we all agree on that.  the colors you see from objects are just the wavelenghts of light that are not absorbed by that object, so therefore are reflected. so we are definately all seeing the same frequencies of light... its easier to understand with sound, if you pick different frequencies, it's a higher or lower pitch.  we can all definately agree on the pitches of sound because we can agree on whether or not the pith is higher than another pitch. if you pick a frequency on the electromagnetic spectrum in the visible light range, that frequency will correspond to a certain color. violet is the color with the wavelength of the highest frequency, meaning it has the highest energy(E=hf where h is planck's constant so energy is directly proportional to frequency.) red has the lowest frequency, and therefore energy. the colors go in order of lowest to highest energy as follows: red, orange, yellow, green, blue, violet. it is is definate that what everyone views as violet is what has the highest energy, and what everyone views as red has the lowest.  and the colors as we know them, kind of blend into each other as you go up in energy, like starting with red you can have red orange and keep adding orange till you get to orange, then add some yellow and so on.. the colors blend nicely. if someone viewed lets say green instead of orange... well then red and green wouldnt mix so well now would they? if you think about it, the colors go "up" in energy steadily just as sound goes up in pitch steadily, so we do all view colors the same.  i hope i conveyed my thoughts properly and that made sense :)
589374
They depict blood flow and the color depicts direction and velocity of flow.
75140
They are wrong...It is the carotenoids. I am 100% positive! See wikipedia.org below is an excerpt from wikipedia answering the question. It is also in my AP biology book:\nTheir color, ranging from pale yellow through bright orange to deep red, is directly linked to their structure. The double carbon-carbon bonds interact with each other in a process called conjugation. As the number of double bonds increases, the wavelength of the absorbed light increases, giving the compound an increasingly red appearance.
9037
Blood is blue when it's not oxygenated, for instance when it's in veins, which return blood to the heart to be refilled with oxygen after it's been used.  Veins are those blue lines you can see under people's skin-- that's blood.  Blood in arteries (which are usually lower than veins and thus not visible through people's skin) is red. \n \nSo, to summarize, red oxygenated blood leaves the heart and goes around to the rest of your body, where it fuels your muscles and organs.  They use up the oxygen, turning it blue.  Via the veins-- those little blue lines that are visible sometimes in people's neck or hands-- the blood returns to be filled again with oxygen. \n \nWhen you cut yourself, the blood becomes oxygenated as soon as it hits the air, so that's why regardless of where it comes from it's always red by the time you see it. \n \n<3
231767
First off ignore those claiming that the blood in your veins is blue. The blood  everywhere in your body is red, always. All the time. It is never blue. Any blue colour is an illusion it is just an illusion.. Blood fresh from the lungs in bright red, blood in the veins is dark red. But blood is never any colour but red unless you have been poisoned and are about to die.\n\nThe blood that you can see in the veins under your skin appears to be blue because the skin and the vein itself absorbs red and yellow light preferentially. That means that only the blue light returns to your eye. But it is entirely an illusion, and the blood in the veins is a dark red colour.\n\nAnyway, the reason that the blood is red is because it contains red blood cells, and red blood cells in turn are packed with a molecule called haemoglobin. Haemoglobin is a red colour, and that is what makes blood red.