Article Questions – “The Stuff of Life: Why Water



Article Questions – “The Stuff of Life: Why Water ? ” 20151.Ocean and fresh water creatures literally swim in it. What is “it” ? ____________2.Land creatures have found a way to carry their “_______________” around with them.____3.Bacteria have learned to adapt to all of these conditions except:a)living at the boiling point of water at deep sea ventsb)living with high levels of radiation in a nuclear reactorc)living without liquid water4.Individual cells of Earth organisms contain ______ - ______ % water.5.The desert kangaroo rat doesn’t drink its water. Instead, it uses ___________ to breakdown _________________________ such as sugar to produce its own water supply.6.For life on Earth, there appears to be a limit beyond which adaptation just isn’t possible.That limit is set by:a)oxygenb)hydrogenc)waterd)daylight7.The “habitable zone” for life around a distant star would be the range of distanceswithin which _________________ water would be stable on a planets surface.8.Although it lies beyond the habitable zone, Jupiter’s moon __________________ maysustain an ocean of liquid water by tidal heating.9.It is clear that the liquid phase of matter offers important advantages to life forms:a)In liquids, molecules may _____________________ (to form solutions).b)The liquid environment allows the ______________________ of key moleculesfrom one location to another.c)As a result, ___________________ ______________________ can be sustainedby an ongoing supply of ingredients which the liquid can carry in.d)Key products of reactions can _________________ or be moved to where they are needed and _________________ can be eliminated.10.Life in the ________________ phase would face enormous difficulties: any large,_____________ molecules would tend to settle quickly out of a gas and would not beavailable for further (chemical) __________________.11. Water is so good at dissolving many molecules that it is called the “universal _________”12.The oxygen atom in a water molecule exerts a much _______________ attraction for electrons, so the electrons spend most of their time near the oxygen end of the molecule.13.As a result, the oxygen end of the water molecules has a partial _____________ charge,while the hydrogen end has a partial _____________________ charge.14. Because of the negative & positive ends, chemists say that H2O is a ________ molecule.15.When a solute (such as salt) is put into the water, the hydrogen atoms form a weakbond with the [ positively or negatively ] charged ends of the solute (Cl- in salt).16.Liquid ammonia is another good polar solvent, but ammonia is not _______________ at the temperatures found on Earth’s surface.17.On much colder worlds, where __________________ would be liquid but water wouldbe frozen, ____________________ might be the “obvious” choice for universal solvent.18.If life on another planet was based on liquid hydrocarbons, it would have to be radicallydifferent from life on Earth, because hydrocarbons are _____-____________ molecules.19. When water molecules come in contact with non-polar solutes, they arrange themselves into ________ around the solutes, ______________ the non-polar molecules into clumps.20.Terrestrial biology relies on certain types of proteins called_______________________.21.Water is crucial to the ability of enzymes to assume just the right _________________.22.Unlike most other substances, solid water (ice) will _____________ on liquid water.____23.What would happen to lakes if ice built up on the bottom of the lake instead offorming on top of the water?a)The bottom ice would accumulate year after year.b)The bottom ice would remain insulated from melting during the summer.c)Eventually, the lake would completely fill with ice.d)All of the above would happen.___ 24. Which environment is more likely to experience great temperature fluctuations daily? a) Humid, ocean-covered Earthb) Dry, dusty Mars25.One unanswered question regarding water and life on Earth is how ____________ evergot put together, since water tends to split amino acids apart, not put them together.T or F 26. While water presents many advantages to life, it poses its own challenges, too.T or F 27. These challenges have been overcome on Mars and Europa, but they have not been overcome on Earth.Video Discussion Questions – “Where are the Aliens?”1. [14:15] When a distant star has a huge planet orbiting around it, the star _______________back and forth (blueshifting as it comes forward and then redshifting as it goes away).2.51-Pegasi, the first extrasolar planet discovered, is Jupiter-sized. Unlike Jupiter,which takes 12 years to orbit the sun, 51-Pegasi takes ___ __________ to orbit its star.3. The planet _________ protects Earth by slinging asteroids and meteoroids back into space.____3.For a solar system to have an Earth-like planet, is it better to have a “Jupiter”:Closer in to the sunorb) Farther out (like our Jupiter)5.About how many Earth-like planets are estimated to exist in the Milky Way?About ____________________________________6.Life on Earth is based on the chemical element ___________________ (symbol = C).7.In the past few years, biologists have found evidence of life _____________________.8.What chemical compound, essential to life, do we find on Earth but nowhere else(so far)? Liquid ______________________ (formula= H2O)9.Does Mars have liquid water now? ______ Did Mars used to be a “wet” planet? _________10.If there is liquid water on Jupiter’s moon Europa, where will it be?At the surface – melted by intense sunlightDeep inside, melted by tidal forces created by gravity of Jupiter and nearby moons [32:55.] ................
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