Hello everyone, my apologies for taking so long to get this next awareness article up.
You will be given class time to complete your last 3 awareness articles.
Period B Science will be in Mr. Griers computer lab on Jan 15th.
Period C Science will be in the library computer lab on Jan 16th.
You should be able to get a minimum of 2 articles done in that time.
All articles should be complete by Friday, January 23rd, 2009.
Tuesday, January 13, 2009
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Title: Bacterial Cell
Author: Hank Seifert
Date:
Source: http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Bacteria%2522&c=15&t=1&ste=21&docNum=CV2642150026&st=b&tc=63&tf=0
This article is all about the different types of bacteria that exist on earth, and can be found in different environments/surroundings. Bacteria are also known as prokaryotes can exist in water, soil, and on rocks. There are also bacteria on animals, bugs, plants, and people. Some of the bacteria are beneficial to the human body; some help our immune systems and some bacteria in the human body are helpful for decomposing minerals that our bodies cannot decompose such as E-coli. The bacterial cell has two major compartments, the cytoplasm and the cell envelope. The article also talks about how bacteria cells grow by the process of binary fission, a process where one cell doubles itself then splits into two identical cells called daughter cells. The daughter cells can then continue the process of binary fission. Bacteria can also have different sizes, the smallest being mycoplasmas which can range from 0.1 to 0.25 micrometers in diameter, and the biggest being epulopiscium fishelsoni which is 250 micrometers long and is visible to the eye. In conclusion, a bacterium has many interesting facts, not only can it be dangerous, but it can be healthy and safe to be around.
Other Sources:
http://www.ucmp.berkeley.edu/bacteria/bacteria.html
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Eubacteria.html
Title: Bacterial Cell
Author: Hank Seifert
Date: January 15, 2009
Source: http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Bacteria%2522&c=15&t=1&ste=21&docNum=CV2642150026&st=b&tc=63&tf=0
This article is all about the different types of bacteria that exist on earth, and can be found in different environments/surroundings. Bacteria are also known as prokaryotes can exist in water, soil, and on rocks. There are also bacteria on animals, bugs, plants, and people. Some of the bacteria are beneficial to the human body; some help our immune systems and some bacteria in the human body are helpful for decomposing minerals that our bodies cannot decompose such as E-coli. The bacterial cell has two major compartments, the cytoplasm and the cell envelope. The article also talks about how bacteria cells grow by the process of binary fission, a process where one cell doubles itself then splits into two identical cells called daughter cells. The daughter cells can then continue the process of binary fission. Bacteria can also have different sizes, the smallest being mycoplasmas which can range from 0.1 to 0.25 micrometers in diameter, and the biggest being epulopiscium fishelsoni which is 250 micrometers long and is visible to the eye. In conclusion, a bacterium has many interesting facts, not only can it be dangerous, but it can be healthy and safe to be around.
Other Sources:
http://www.ucmp.berkeley.edu/bacteria/bacteria.html
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Eubacteria.html
Fossilization of Bacteria
"Fossilization of bacteria." World of Microbiology and Immunology
Fossils of blue-green algae have been found in rocks over four billion years old. A specific type of magnetobacteria form magnetic crystals inside the algae's cells. These crystals remain after the plant has decayed. The fossilization depends on the bacteria's abitlity to trap sediment from the surrounding water. Over time and under pressure, the sediment fomrs into rock and encases the bacteria. The magnetic crystals replace the bacteria's organelles and leave a three dimensional image. Other bacteria can create a carbohydrate network around themselves then fossilize.
Sources:
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Bacteria%2522&c=11&t=1&ste=21&docNum=CV2644650176&st=b&tc=63&tf=0
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Bacteria%2522&c=13&t=1&ste=21&docNum=CV2641950179&st=b&tc=63&tf=0
On the Appearance of Tears.
AUTHOR: Clanon, Kathleen
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Crying%3A+The+Natural+and+Cultural+History+of+Tears+%28Book%29%2522&c=1&t=2&ste=22&docNum=A59579137&st=b&tc=22&tf=0
This article is a review of another article written by Tom Lutz, which walks about the study of tears. There have been extensive studying on why people cry, how long they cry, and what makes them stop. Connections have been made between crying for many different reasons. For instance why do adults cry of happiness and children do not. This article says that the adults only cry tears of anticipated loss, not happy tears. They know that death will be in the future. The article makes many points that tears are powerful and very universal that people on every corner of the world have.
By: Lauren
http://www.geocities.com/kidhistory/trauma/tears.htm
http://www.usnews.com/articles/science/medical-science/2008/11/20/the-physics-of-teardrops.html
Title: Solar System
Author: Martin Beech
Date: January 15th 2009
Source: http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Solar+system%2522&c=2&t=1&ste=21&docNum=CV2644032065&st=b&tc=63&tf=0
A solar system consists of the sun, eight major planets, five dwarf planets, the moons that orbit each planet, and many asteroids and comets! There were originally 9 planets in the solar system, but in 2006, Pluto was demoted to being a dwarf planet because it was too small. The most important and largest object in the solar system is the sun. Its diameter is 109 times the diameter of the earth. The sun’s surface is about 6000 degrees Celsius (about the same temperature as the earth’s core). It is impossible to know how the solar system formed because no one was around when it happened. One theory is that the solar system was formed through the collapse of a spinning cloud interstellar gas and dust. Everything in the solar system orbits or revolves around the sun. The closest planet to the sun in Mercury, then Venus, then Earth, then Mars, the Jupiter, then Saturn, then Uranus and last but not least Neptune.
Additional Sources:
http://www.kidsastronomy.com/solar_system.htm
http://www.nineplanets.org/
by Kyla
Title: Clone and Cloning
Author: David Petechuk
Date of Article: 2008
Source: http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=Cloning&c=3&t=1&ste=21&docNum=CV2644030504&st=b&tc=63&tf=0
This article talks about the history of cloning, the types of cloning, the cloning process, along with the problms and ethics of cloning.
A clone is a cell that is exactally the same as the cell which it was derived from. The clone cell is identical to the one which it was cloned from; it has the same DNA, RNA, and has the same structure of molecules as the original cell.
The three types of cloning are gene cloning, twinning, and a process using nuclear transfer of genetic material. Humans have been experimenting with plant asexual reproduction (such as grafting and stem cuttings)for more than 2000 years. Cloning in the labratories began in 1958 with carrot plants, and the first animal cloning began in 1964 with tadpoles.
Cloning or specific genes in a lab begins with removing a certain length of DNA from a host an organism (animal, plant, ect) and is then placed in another DNA molecule , which is called a vector (recombinant DNA molecule) molecule). The vector is used to put the gene into a host cell (ex. yeast)where the DNA is able to produce many copies of itself.
One of the problems with cloning is that the clones of animals suffer from age related diseases and tend to die prematurely. Though clones may appear healthly , they are very volnurable to infections and hepatic failure.
Cloning is also good though; for research purposes in a labratory, though some questions are being asked if scientists are guilty of the of cloning too much. Even though there is a lot of concern that the abuse of cloning from scientists, it is most likely that the cloing will not stop, despite what peoples concerns are. Human cloning has been banned in most countries, but the animal and plant cloning will continue.
Newtonian physics
Table of Contents Source Citation
Newtonian physics encompasses the contributions of Isaac Newton (1643-1717) to the understanding of the physics of motion. Newton’s contribution to science also includes his refinement of the scientific method, which concentrates on a precise, mathematical description of the physical world. Using this approach, Newton explained both the motions of heavenly bodies and the motions of objects on or near the surface of Earth by formulating four simple laws: his three laws of motion and the universal law of gravitation. This contribution of Newtonian physics represents one of the most remarkable achievements of humanity's intellectual development.
Newtonian physics radically modified the two-thousand year-old prevailing concept of the universe which was based on Aristotle's physics. These foundations were first shaken by Galileo during the Italian Renaissance and by Kepler's laws of planetary motion, but it was Newton who formulated the exact relationship between force and motion. Newton revolutionized the view of the universe by showing that the same physical laws apply to all matter, whether inert or living. Aristotle (384-322 BC) tried to explain the underlying reasons as to why objects move and he proposed that "natural motion" (such as freefall) resulted from the objects "wanting" or preferring to lie in their natural state--in this case, on the ground. Aristotle also described another type of motion, "voluntary motion," such as that shown by a person going from point A to point B because he "wants to." Finally, he believed that a third type of motion, "forced motion," could occur due to an object forcing another to move.
Newton formulated the modern concept of force, starting with the insight that only interactions between objects can affect motion. Thus, in Newtonian physics, there is only one cause for a change in motion, and it is simply force. Forces may be of a different nature, but they all have the same effect when they are unbalanced, which is to produce changes in the motion of a body. Aristotle believed that forces could only act on objects that touched each other; Newtonian physics describes such forces as contact forces but also accounts for noncontact forces (like gravitational forces).
The starting point of Newtonian physics are Newton's three laws of motion. The first one states that all objects have inertia; that is, an object will remain at rest or in uniform motion unless acted upon by some outside force. In other words, an object initially at rest will remain at rest if the total force acting on it is zero, and a moving object will remain at a constant velocity (constant speed and direction). If the total force on an object is not zero, then the object must accelerate.
Predicting the resulting acceleration is the subject of the second law, which states that an object's acceleration is directly proportional to the total (net) force acting on the object and is in the same direction as that force. This acceleration is also inversely proportional to its mass, meaning that more massive objects are less apt to accelerate for a given net force. The most common form of Newton’s second law is F = ma, or force is equal to the product of an object’s mass and its acceleration.
Newton's third law defines force as the interaction between two objects, and states that for every action there must be an equal and opposite reaction. Thus forces must occur in equal and opposite pairs: whenever object A exerts a force on object B, object B must also be exerting a force on object A. The two forces are equal in magnitude and opposite in direction.
Newtonian physics was firmly entrenched in scientific belief until the advent of Albert Einstein’s special and general theory of relativity in the early twentieth century. Since that time, Newtonian physics has also been referred to as "classical physics" or pre-relativistic physics, because its laws describe the physical world in a way that cannot account for relativistic gravitational effects. In other words, Newtonian laws are valid only when gravitational potential energy differences are small compared to mc2. The laws are also invalid in the analysis of objects with speeds that approach the speed of light. Thus, the physics of very massive and very fast objects can only be described by relativity. Newtonian physics also fails to fully describe the physics of very small objects (such as electrons, atoms, and elementary particles), which are accounted for in quantum theory.
Newton’s laws are valid in frames of reference moving at constant velocities well below the speed of light. Frames of reference moving at constant velocity relative to one another are called inertial frames of reference. In order to apply Newton’s laws in accelerated frames of reference, fictitious (imaginary) forces must be introduced to explain the motion of objects. For example, when a car suddenly stops, an unrestrained passenger will keep moving forward through the windshield. Relative to the surface of the earth, Newton’s first law of inertia clearly explains this observation. Relative to the car (a non-inertial reference frame), it appears as if something pushes the passenger forward. This "something" is not a true force according to Newton’s third law, and thus is referred to as a fictitious force. While the revolution in physics brought about by relativity has clearly shown these limitations of Newton's laws, Newtonian physics maintains a range of validity for many applications in the physical world.
Source Citation: Laberge, Monique. "Newtonian physics." World of Physics. Ed. Kimberley A. McGrath. Online. Detroit: Thomson Gale, 2007. Science Resource Center. Gale. 15 January 2009 (http://galenet.galegroup.com/servlet/SciRC?ste=1&docNum=CV2434500339)
Document Number: CV2434500339
Newtonian physics
Newtonian physics encompasses the contributions of Isaac Newton to the understanding of the physics of motion. Newton’s contribution to science also includes his refinement of the scientific method, which concentrates on a precise, mathematical description of the physical world.
Newtonian physics, there is only one cause for a change in motion, and it is simply force. The starting point of Newtonian physics is Newton's three laws of motion.
In order to apply Newton’s laws in accelerated frames of reference, fictitious (imaginary) forces must be introduced to explain the motion of objects.
Tsunami
"Tsunami." World of Earth Science. Online. Detroit: Gale, 2007
Tsunami are seismic sea waves that have a series of very long wavelength oceans waves generated by the sudden displacement of large volumes of water. Tsunamis are usually mistaken by tidal waves but really there nothing like tidal waves. In open water tsunami can travel up to 760 km/h. some tsunami height when it reaches inland can be up to 200 feet and can make extreme damage to flat cities. Tsunami has the same effect as when you drop a penny into a bowl of water and if makes the little waves. When the tsunami finally makes it into the shore line it gets smaller because of the friction of the sand and the wave at the bottom of the ocean of lake.
Websites
http://galenet.galegroup.com/servlet/SciRC?ste=1&docNum=CV2645100454
http://oceanservice.noaa.gov/websites/retiredsites/sotc_pdf/PAR.PDF
Steven Robillard
Robotics are an unavoidable part of the future of humaity. For years we have been using robotics in factories to perform tasks that may prove to be a little too dangerous or uncomfortable for human beings, or may just to reduce cost of the manufacturing process. Robots are are slowly being introduced into our medical world. They have been in hospitals since the 1970’s performing menial, tasks. Experts are predicting that is soon going to change very quickly within the next few years. Right now around 5% of all military hospitals have robotic assistants, they are not your average walking calculators. These robots ASSIST in performing minimal risk surgeries. They have the ability to emulate a surgeon’s movement, even replicate them based off of movement data files. They have also been used to operate remotely if there is believed to be a risk with operating on a particular patient. As we continue progressing towards the future will shall see more of our metallic friends assisting us in our everyday lives!
Sources:
http://search.ebscohost.com/login.aspx?direct=true&db=afh&AN=6596453&site=ehost-live
http://search.ebscohost.com/login.aspx?direct=true&db=afh&AN=22437193&site=ehost-live
Title: Renewable Resources
Author: Kimberly A. McGrath
Date of article: 2008
Source:http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Renewable+energy%2522&c=4&t=1&ste=21&docNum=CV2434500444&st=b&tc=31&tf=0
The world is running out of precious fossil fuels that provide power with the whole world. Combustion engines in vehicles all rely on them, and almost all the power in countries like China is from fossil fuel plants. When/if fossil fuels are depleted; most of the world will be in trouble. That is why scientists are putting in research for alternate renewable sources of energy. This article pretty much just describes what solar energy, wind energy, bio-energy, geothermal energy, hydropower, and tidal energy are. The problem is that most of these power sources are entirely dependant on what the weather is like outside (with the exception of hydro and bio). Most of the energies are also fairly inefficient and require large-scale plants to provide a bit of energy. Bio-diesels are also bad because they require an absurd amount of corn, soybeans, etc. just to create a tiny amount of fuel. Then vegetable prices skyrocket and a food-shortage ensues just to create a poor source of fuel. In my opinion, majority of research should focus on nuclear fusion because it is the ultimate source of limitless renewable energy.
Title: Endangered Species
Author: Unknown
Date: January 15th, 2009
Source: "Endangered species." World of Biology. Ed. Kimberley A. McGrath. Online. Detroit: Thomson Gale, 2008. Science Resource Center. Gale. 15 January 2009
An endangered species is a species whose numbers have become so small, that it may soon become extinct even regardless of human intervention. There are four different classifications that the World Concervation Union use to rank endangered species. The four categories are Endangered, Critically Endangered, Threatened or Rare. Critically Endangered refers to a species that will not survive without human intervention and protection. A Threatened Species is one that may still be abundant in their own habitat but has a quickly declining population. A Rare Species is one that is considered at risk because of low overall population numbers. Some of the main factors that contribute to endangering a species include; commercial and sport hunting that is not managed properly, competing species overtake the primary food sources, or a species is killed to protect livestock and crops. One of the very first species placed on the United States’ endangered species list was the bald eagle. After the first Endangered Species Act was first passed in 1966 and then later revised in 1973, cooperation from local governments have helped to develop plans and methods to protect and restore endangered and threatened plants and animals. This act has been successful, for since the act was passed, fewer than 1% of the listed species have become extinct.
Other Sources:
http://www.endangeredspecie.com/
http://www.worldwildlife.org/species/
Pollution
Source: Richmond, Elliot. "Pollution". Animal Sciences. Ed. Allan B. Cobb. Online. Detroit: Macmillan Reference USA. 2008
Pollution can be described as a change in the chemical, physical or biological properties of the soil, air, water or other parts of the enviroment that affect humans and other living things. After pollution takes place, the thing that has been polluted is no longer good to use. This is not good for the Earth's resources if they get polluted. It is also not good for the Earth's health or every living organism's health. A lot of pollutants come in the form of solid, liqiud or gas chemicals created by by-products of manufacturing industries. Pollution also occurs in the forms of excessive heat, noise and light and electromagnetic radiation. Pollution also occurs from human's everyday waste disposal. For example, the CO2 emmissions that people all over the world are creating is a large example of pollution caused by the human race. CO2 emissions are very hard on the earth's health, because CO2 emissions has a large part to do with the excessive warming of the Earth. Another example of pollution that people create is, just everyday waste. For example, the average american has made 1,500 lbs of waste in a year! That's a lot, its a major problem because most of that waste is just going to be sitting in landfills. Pollution is a a big problem all over the world, but there is many simple things everyone can do to reduce it such as, recycle, carpool or ride your bike.
Cancer
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Cancer%2522&c=2&t=1&ste=21&docNum=CV2430500062&st=b&tc=63&tf=0
Cancer is a class of diseases in which certain cells lose their ability to regulate cell division. Basically they start to deform and multiply rapidly and infect other cells in the body, the main concern is if the serious makes its way the a vital organ, if it reaches it, it can cause death. There and many different things that cause the chromosomes in the cell to deform and mutate the cells that surround it some main causes of cancer are, Ultraviolet radiation, x-rays, viruses, and some chemicals. Cancer is not specifically a human disease.
Title: Human Hair: The Next Green Fertilizer?
Author: Emily Sohn
Date: Jan. 15, 2009
Source: http://dsc.discovery.com/news/2009/01/15/hair-fertilizer.html
Human hair fertilization, the newest “Go Green” solution. Scientists are experimenting with adding human hair in addition to other waste product, including sewage sludge, cow manure, and sheep wool, to increase the growth of crops. A commercial company known as SmartGrow has already explored this alternative to traditional fertilizers. SmartGrow has created a fertilizing mat containing human hair that is placed above or bellow plants during gardening. This method proves to retain more moisture, prevent weed growth, and adds nutrient to the soil. To further prove these results, tests have been done with lettuce and wormwood seeds. The seeds were planted individually in green houses, each with either chemical fertilizers, hair waste, water-soluble fertilizer, or no additives at all. The results showed that the chemical fertilizer preformed best, but with the hair waste fertilizer close behind. Another round of experiments were done, this time with feverfew and poppies. The second round of seeds were placed in hair waste fertilizers that had had more time to break down (about a month). This proved to significantly improve the effect on the plants. To control the speed in which the hair waste fertilizer effects plants, they say they may need to mix in chemicals fertilizers. Though the human hair fertilization still has a few glitches, scientists are working on the further improvement of organic fertilizers.
Additional Links:
http://www.sciencedaily.com/releases/2008/12/081229104704.htm
http://www.msnbc.msn.com/id/28509911/#storyContinued
Sabrina Moche
Title: Renewable Energy
Author: Marci Bortman and Peter Brimblecombe
Date: 2008
Source: http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Renewable+energy%2522&c=2&t=1&ste=21&docNum=CV2644151162&st=b&tc=31&tf=0
The 1980s and 1990s were decades of cheap and abundant fossil fuel, and U.S. development of efficiency and renewable energy stagnated. The share of U.S. primary energy met by renewables--mostly large-scale hydropower from mega-dams like the 6.8-gigawatt Grand Coulee Dam power station--peaked in the mid 1990s at about 7.5%, then began to decline. By 2005 only about 6% of U.S. energy came from renewables, and about 45% of that came from large hydropower plants--about the same figures as in 1979. However, in the late 1990s and early 2000s renewable energy again became prominent thanks to increasing concerns over rapidly rising oil prices, pollution, coal mining, and global warming. Global warming is driven largely by carbon dioxide released from the burning of fossil fuels; most forms of renewable energy do not contribute to global warming.
Other Sources: http://www.re-energy.ca/
http://www.planetfriendly.net/energy.html
title: Overactive Bladder
Author: Ken R. Wells.
source:http://galenet.galegroup.com/servlet/SciRC?sgsl=bi&locID=winn39111&bi=SU&sgos=%2522Diseases%2522&sgcmd=REL&bt=%2522Bladder+Diseases%2522&c=3&t=1&ste=21&docNum=CV2642413472&sgit=28&st=b&tc=31&sgsditem=27_3_1&tf=0
Year published:2006
People who have an overactive bladder cannot control their urinating habits. Even when they hear water running or drink water or sleep they may leak large amounts of urine. This disease is popular among public, affecting 17 million Americans. Some causes for this unexpected bowl movement may be because of inappropriate bladder contractions, reflex inconsistence, and other diseases and injuries. Such as, Parkinson’s, Alzheimer’s, stroke, and brain tumours. Professionals describe theses symptoms as not only overactive but unstable and spastic. Damage to the nervous system such as the spine also has a large effect on the bladder. This disease can be treated by a family doctor but some people prefer to see a specialist such as an urologist. To treat or control this disease you can either take various antibiotics to strengthen and relax certain muscles that control the bladder (but can become very costly) or, you can change your diet by avoiding spicy and acidic food, alcohol, caffeine, etc. There are different kinds of herbal teas that retain fluid. To avoid constipation do not consume too many whole grains, fruits, or vegetables. There is also different treatments you can try to strengthen your urinary tract and help your bladder sustain your urine for a reasonable amount of time.
other sources:http://www.patient.co.uk/showdoc/27001041/
Title: Kepler's laws of planetary motion
Author: Katharine Dunn
The article is discussing Kepler’s laws of the motion of the planets, and how he came up with them. The first law is that planets travel in elliptical orbits, around the Sun. Kepler’s second law means that a planet moves more quickly (in its orbit) when it is closer to the Sun. The third law Kepler came up with is that the square of a planet's period of orbit around the Sun is directly proportional to the cube of a planet's average distance from the Sun.
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Newton%27s+laws+of+motion%2522&c=4&t=1&ste=21&docNum=CV2434500262&st=b&tc=55&tf=0
Links:
http://www.splung.com/content/sid/2/page/kepler
http://library.thinkquest.org/04apr/00533/Text-Only/kepler's_laws.htm
Title: Endangered Species
Author: Unknown
Date: January 15th, 2009
Source: "Endangered species." World of Biology. Ed. Kimberley A. McGrath. Online. Detroit: Thomson Gale, 2008. Science Resource Center. Gale. 15 January 2009
An endangered species is a species whose numbers have become so small, that it may soon become extinct even regardless of human intervention. There are four different classifications that the World Concervation Union use to rank endangered species. The four categories are Endangered, Critically Endangered, Threatened or Rare. Critically Endangered refers to a species that will not survive without human intervention and protection. A Threatened Species is one that may still be abundant in their own habitat but has a quickly declining population. A Rare Species is one that is considered at risk because of low overall population numbers. Some of the main factors that contribute to endangering a species include; commercial and sport hunting that is not managed properly, competing species overtake the primary food sources, or a species is killed to protect livestock and crops. One of the very first species placed on the United States’ endangered species list was the bald eagle. After the first Endangered Species Act was first passed in 1966 and then later revised in 1973, cooperation from local governments have helped to develop plans and methods to protect and restore endangered and threatened plants and animals. This act has been successful, for since the act was passed, fewer than 1% of the listed species have become extinct.
Other Sources:
http://www.endangeredspecie.com/
http://www.worldwildlife.org/species/
Title: Motion
Motion is the process by which something moves from one position to another. A change of position involving time, velocity, and acceleration. Motions can classified as linear. In circular motion, velocity is always parallel to the direction of motion and perpendicular to the radius of motion. The acceleration required to change the velocity's direction, called centripetal acceleration, is always perpendicular to the velocity and toward the center of motion. To change the velocity's magnitude, acceleration is required in the direction of the velocity. This is applicable to curvilinear motion in general. The position of an object must be given (or implied) relative to a frame of reference, and the object's motion is then described relative to this frame. Within this frame, position, change of position, velocity, and acceleration require a magnitude (how much) and a direction, both being equally important for a complete description.
By: Katie
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Motion%2522&c=4&t=1&ste=21&docNum=CV2434500326&st=b&tc=63&tf=32
Title: Motion
Motion is the process by which something moves from one position to another. A change of position involving time, velocity, and acceleration. Motions can classified as linear. In circular motion, velocity is always parallel to the direction of motion and perpendicular to the radius of motion. The acceleration required to change the velocity's direction, called centripetal acceleration, is always perpendicular to the velocity and toward the center of motion. To change the velocity's magnitude, acceleration is required in the direction of the velocity. This is applicable to curvilinear motion in general. The position of an object must be given (or implied) relative to a frame of reference, and the object's motion is then described relative to this frame. Within this frame, position, change of position, velocity, and acceleration require a magnitude (how much) and a direction, both being equally important for a complete description.
By: Katie
http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Motion%2522&c=4&t=1&ste=21&docNum=CV2434500326&st=b&tc=63&tf=32
Title: Cloning
Author: Marci Bortman and Peter Brimblecombe
Date of article: 2003
Source of article: http://galenet.galegroup.com/servlet/SciRC?locID=winn39111&bi=SU&bt=%2522Cloning%2522&c=4&t=1&ste=21&docNum=CV2644150278&st=b&tc=63&tf=0
Cloning is the ability to make an exact copy of the original source without sexual reproduction. Cloning became news in 1997 in Scotland where scientists cloned a sheep named Dolly. Dolly was the first adult mammal ever cloned. There are two types of cloning Blastomere separation, where the embryo is split after it is fertilized by sperm. The other type is referred to as nuclear transfer where scientists transfer genetic material from an adult female to an egg in which the genetic material had been removed.
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