Results:
Pouring the sodium silicate solution into the beaker containing the alcohol produced an immediate reaction. The polymer turned a creamy color and crumbled easily. It refused to stick together at first, but when we did get it to stick together, it looked like a snowball. The mixture was translucent a shiny.
While forming the ball, the polymer felt sticky and slimy until we got the polymer dried a little bit. However, the first time we dried the polymer, it crumbled, so the second time we let it air dry.
The rebound of the normal polymer was about 8cm. It also bounced around a lot. When we refrigerated the polymer, it became smaller and harder. This caused it to bounce higher.
Questions:
1. What characteristics are similar between your two types of polymers you have made? Differences?
The two polymers were similar because their solutions joined to create another object. The two polymers are different because the first polymer was more flexible and held shapes better. The second polymer was harder to shape and crumbled quite often.
2. Most commercial polymers are carbon based. What similar properties do carbon and silicon share that may contribute to their abilities to polymerize?
Carbon and silicon both make four chemical bonds which gives the capability to branch out in four directions. This is also how the two are able to make long chains.
3. Plastics are made of organic (carbon based) polymers. What similarities do the silicone polymer share with plastics?
They both use organic materials, however, while silicone is completely made form organic sources, plastic is only half organic. Monomer plastics are mostly made from organic substances, which make plastics and silicone even more similar. Both plastics and silicones are key ingredients to making polymers. Silicones can also make a type of plastic. It is said that silicone is able to replace plastic in toys, which would make them much safer.
4. How did you know that a chemical reaction had taken place when the two liquids were mixed?
We knew that a chemical reaction had taken place between the two liquids because they started to show a physical change.
5. How could you find out what liquid was pressed out of the mass of crumbled solid as you formed the ball?
We could have tested the DNA of the liquid to find out what it was.
6. Compare you ball with those of other members of the class. How many properties can you compare (e.g., diameter of sphere versus height of bounce)?
The group in front of us had made a much larger polymer. It was about a quarter in size, while ours was about a dime. Also, their polymer did not crumble. We think this could be because our group held it too much.
Conclusion
This experiment was much like the other one we did in the form of basic procedures and results. However, both of the polymers would yield different results when used for daily purposes. For example, the glue polymer is more flexible and would be able to withstand much more strain than the sodium silicate polymer. The sodium silicate polymer is much more logical to create however, because it is made from sustainable substances while glue can melt. It is rather interesting to see how substances of the same characteristics can have so many different properties that makes them fell different.
Monday, March 14, 2011
Polymer Investigation
Our group was: Haley Ciccone, Holden Long, and Keara Burke
This is the lab sheet our group put together.
Problem: How does the tacky glue change the physical and chemical properties of the polymer?
Hypothesis: When the white Elmers glue (polyvinyl acetate) is replaced with tacky glue, the resulting polymer will be stretchier.
Background Info: Tacky glue is thicker than normal white glue. It dries faster and is a stronger adhesive. Tacky glue is also a PVA substance, meaning it must be kept from freezing. Otherwise it will become extremely stiff and become hard to move. When dehydrated, it
Title: Tacky Glue Polymer
Problem: How does the tacky glue change the physical and chemical properties of the polymer?
Hypothesis: When the white Elmers glue (polyvinyl acetate) is replaced with tacky glue, the resulting polymer will be stretchier.
Background Info: Tacky glue is thicker than normal white glue. It dries faster and is a stronger adhesive. Tacky glue is also a PVA substance, meaning it must be kept from freezing. Otherwise it will become extremely stiff and become hard to move. When dehydrated, it
will peel off of glass, metal, and plastic.
Materials:
- Tacky glue - polyvinyl acetate
- Plastic spoon
- 200 or 250 mL beaker (Pyrex)
- 500 mL beaker (Pyrex)
- Stirring rod
- Graduated cylinder
- 525 mL of water
- 2 tsp of borax (hydrated sodium borate)
- cm ruler
- Square of paper towels (or any absorbing material used for cleaning)
- Refrigerator (with an average temperature of 1.7- 3.3 degrees Celsius
1. Arrange the materials at the head or front of a flat surface.
2. Add 400 ml of water to the larger beaker.
3. Add 2 tsp. of borax to water and stir until dissolved.
4. Pour 40 mL of tacky glue into small beaker.
5. Add 5 mL of water to the adhesive.
7. Clean the stirring rod.
8. Stir the borax compound.
9. Blend the glue and water for about 30-60 seconds, or until fully integrated.
11. Calculate 25 mL of the Borax solution that was just stirred with the graduated cylinder.
12. Deposit the solvent matter into the small beaker.
13. Coalesce the two elements, both solvent and solute, with the stirring rod.
14. Examine its features and record any results.
15. If needed, test the rebound and flexibility of the polymer just before cleaning the materials.
Stretchy Test Procedures: One ruler and a flat surface (preferably a level table) is needed to perform this experiment. After the polymer has successfully been formed, and is set to a comfortable, pliable room temperature, the trial(s) may commence. Align the ruler with the edge of the table; have the side with the centimeters facing the edge. Mold the sticky substance into an oval shape. Firmly grasp the polymer with both hands, leaving about one to two centimeters of material between fists. Stretch the matter at a controlled pace so to be sure that observations are able to be recorded, as well as allowing the polymer to adjust to the change in physical properties. How do you know when to stop stretching? When the link between the two wedges disperse in thin filaments, or the bridge suddenly splits, then it is a definite sign to halt the operation and record significant data. Depending on the fiber being tested, another ruler may need to be added to the materials in order to document accurate measurements. However, this is just in case the polymer spreads wider than originally expected (30 cm). Also, this test will need to be reiterated two to three more times in order to regulate an average calculation of its break-point. Compare and contrast with previous test results, as well as separate experiments.
Stretchy Test Procedures: One ruler and a flat surface (preferably a level table) is needed to perform this experiment. After the polymer has successfully been formed, and is set to a comfortable, pliable room temperature, the trial(s) may commence. Align the ruler with the edge of the table; have the side with the centimeters facing the edge. Mold the sticky substance into an oval shape. Firmly grasp the polymer with both hands, leaving about one to two centimeters of material between fists. Stretch the matter at a controlled pace so to be sure that observations are able to be recorded, as well as allowing the polymer to adjust to the change in physical properties. How do you know when to stop stretching? When the link between the two wedges disperse in thin filaments, or the bridge suddenly splits, then it is a definite sign to halt the operation and record significant data. Depending on the fiber being tested, another ruler may need to be added to the materials in order to document accurate measurements. However, this is just in case the polymer spreads wider than originally expected (30 cm). Also, this test will need to be reiterated two to three more times in order to regulate an average calculation of its break-point. Compare and contrast with previous test results, as well as separate experiments.
Results:
When we tested the flexibility of the tacky glue polymer, it stretched to 18 cm. We tested the flexibility again after putting the polymer in the fridge. It was able to stretch up to 59 cm. We also tested the rebound. At room temperature, the polymer's rebound was between 8-11. After being cooled, the polymer's rebound was 13.
We found that a different type of glue was enough to change the physical properties of the polymer: for instance, it resulted in much higher flexibility. Our hypothesis was proven correct.
Addiction
The brain is made up of groups of neurons which are responsible for certain tasks. Near the center of the brain is a system called the "reward pathway": its job is to transfer dopamine and create the feeling of pleasure. Recreational drugs work by mimicking the brain's inhibitory and excitatory proteins and abusing this pathway to create a "high" in the user.
These drugs have consequences; they affect the reward pathway's ability to create pleasure and wire other parts of the brain, creating an impulse to continue using a drug (i.e. addiction).
These drugs have consequences; they affect the reward pathway's ability to create pleasure and wire other parts of the brain, creating an impulse to continue using a drug (i.e. addiction).
Sunday, January 9, 2011
Harvest of Fear
Should we Grow GM Crops?
Instructions: Read the page and click YES or NO, reach the next...click YES or NO...etc until you’ve read all the arguments -- You will need to do this 12 times in order for your votes to be tallied. Navigate the site, each of the bold headings below are links within the site
1. What is a GM Crop?
GM stands for genetically modified (although that's a very misleading acronym, and one that probably shouldn't be used). Genetically modified crops have had genes added, removed or modified.
2. List 2 arguments FOR the growing of GM crops
Instructions: Read the page and click YES or NO, reach the next...click YES or NO...etc until you’ve read all the arguments -- You will need to do this 12 times in order for your votes to be tallied. Navigate the site, each of the bold headings below are links within the site
1. What is a GM Crop?
GM stands for genetically modified (although that's a very misleading acronym, and one that probably shouldn't be used). Genetically modified crops have had genes added, removed or modified.
2. List 2 arguments FOR the growing of GM crops
- Genetically modified food potentially means less pesticide and herbicide.
- Genetically modified food is one of the best hopes for feeding a rapidly expanding world population.
3. List 2 arguments AGAINST the growing of GM crops.
- Genetically modified food is believed to present a potential health risk.
- Genetically modified food may have small farmers be indentured to large farms.
*Read some of the reader’s responses.
Engineer a Crop
4. Practice this simulation until you get the largest ears of corn. How many times did it take you?
Fourteen.
What’s for Dinner?
*Click on the foods on the table to see what research is being done to bioenginner the foods.
5. List two foods and desribe how they are being modified.
What’s for Dinner?
*Click on the foods on the table to see what research is being done to bioenginner the foods.
5. List two foods and desribe how they are being modified.
Corn is being modified to have "altered oil profiles, amino-acid compositions, seed color, starch content, and ability to tolerate drought."
Cotton is being modified to have altered fiber quality that is also moth resistant and drought tolerant.
Viewpoints
*Read the article titled “Is GM Food Sufficiently Regulated in the US?”
Do you think food should be labeled if it has been genetically modified? Why or Why not?
Cotton is being modified to have altered fiber quality that is also moth resistant and drought tolerant.
Viewpoints
*Read the article titled “Is GM Food Sufficiently Regulated in the US?”
Do you think food should be labeled if it has been genetically modified? Why or Why not?
There doesn't seem to be any serious reason to not label genetically modified food, besides consumers rejecting the food solely on the basis of being modified, rather than for any known health risks (which is pretty absurd, but apparently this happens often). So, if consumers are responsible enough to not reject a product solely based on being modified, for the sake of "transparent" government and science, genetically modified food should be labeled in the U.S.
Wednesday, January 5, 2011
Cloning in Focus
1. Who is Dolly?
In the context of genetics, Dolly is a cloned sheep, as well as the first mammal to be cloned. Dolly was cloned in Great Britain.
2. When a zygote divides into to separate cells, it is called Artificial Embryo Twinning.
3. Somatic cells are also called: adult cells.
4. In order to clone a gene, a gene is inserted into a strand of DNA, usually a plasmid.
5. In order to create an embryo from a somatic cell, the donor egg cell must have its nucleus removed.
Click and Clone
6. List all the materials needed to clone a mouse.
7. Place the following steps in the correct order.
8. There are two time gaps in the process of cloning. What are they? (ie. what do you have to wait for?) It takes time for the DNA to be reprogrammed and for the chemical to stimulate cell division.
9. What color with (sic) the cloned mouse be? Brown. What is the name of this mouse? Mimi.
Why Clone?
10. Why is cloning extinct animals problematic? Locating the DNA of an extinct species is very difficult.
11. What are some reasons a person might want to clone a human? To allow infertile couples to have "children" and to replace deceased children (although the latter seems awfully questionable).
The Clone Zone
12. What animal was cloned in 1885? The sea urchin.
13. How did Spemann separate the two cells of the embryo of a salamander in 1902? The embryo was split with a baby's hair.
14. The process of removing a nucleus is called enucleation.
15. In 1952, the nucleus of a frog embryo cell was placed into a donor cell. Did it work to clone the animal? No.
16. Can the nucleus of an adult cell be injected into an egg cell and produce a clone? Yes.
17. Why are mammals hard to clone? Their DNA is complex, and their development is largely based on their environment.
18. What were the names of the first two cloned cows? Fusion and Copy.
19. In what year was the National Bioethics Advisory Council formed? 1995
20. The first mammal clone to be produced from an adult (somatic) cell? (sic) Dolly.
21. What do scientists do to adult cells to make them "behave" like embryos? The electric shock technique simulates fertilization by sperm, causing the cell to divide.
22. Transgenic, cloned sheep were used to produce what medical protein? Factor IX
23. What is a stem cell? An undifferentiated cell whose daughter cells may differentiate into other types of cells.
Cloning Myths
24. Briefly describe in your own words, (sic) why CC the cat was not identical in color to Rainbow, even though she was a clone?
Very early in her development, each of Rainbow's cells "turned off" one entire X chromosome - thus turning off either the black color gene or the orange one. In short, the genes are identical, but they are expressed differently.
25. What is "nature vs nurture"?
Nature vs. nurture is the supposed conflict between genetics and parenting: a continuing and stagnant argument over whether or not parenting has a significant influence on the child.
Is it Cloning or Not?
26. For each of the following scenarios, indicate YES (it is cloning) or NO (it is not cloning)
(NO)Sperm taken from a mole goat is combined with a female's egg in a petri dish. The resulting embryo is implanted into the female's uterus to develop
(YES)A sheep embryo, composed of 16 cells, is removed from the mother's uterus and separated into individual cells. Each cell is allowed to multiply, creating 16 separate embryos, which are then implanted in different female sheep to develop to maturity.
(NO)A cow with many desirable traits is stimulated with hormones to produce a number of egg cells. Each of these eggs is fertilized and implanted into a surrogate mother.
(NO) In vitro fertilization
(YES) Cell nuclei from an extinct wolly mammoth are placed into enucleated cow cells.
27. Define or describe each of the following processes (you may need to reset the Cloning or Not Screen)
In vitro fertilization
Fertilization of an embryo by sperm cells within a test tube.
Embryo splitting
An embryo splitting evenly, causing the development of two identical organisms.
Somatic Cell Nuclear Transfer
Creating a clonal embryo using an ovum with a donor nucleus.
Multiple Ovulation Embryo Transfer
A process to produce multiple copies of an animal.
Artificial Insemination
Sperm is placed into a female reproductive track in an attempt to cause fertilization.
What Are the Risks of Cloning?
28. What is one reason why cloning animals has such a high failure rate?
Pregnancy frequently fails.
29. What is a telomere and how does it affect cloned animals?
A telomere is "junk DNA" at the beginning and end of each chromosome.
30. Pick one of the questions to ponder and ....ponder it. Write a brief essay on your thoughts and opinions.
If a clone originates from an existing person, who is the parent?
The term "parent" is a pretty meaningless when applied to artificially produced organisms. After referring to a number of different dictionaries, there appears to be two definitions of "parent": the more common one is "the person who raises a child," which seems pretty self explanatory. The second definition is "one of the two organisms from whom one is immediately biologically descended," but in this case there would only be one person: the organism which is cloned is, by definition, a clone of itself. Obviously refutable paradoxes in the English language are such fun!
In other words, there are two different kinds of parents: biological and social. Biological parents are the entities from which an organism descends. Most organisms only have biological parents; they are not raised, and learn to survive on their own (i.e. spawning salmon). Social parents are organisms which raise a child (not necessarily their own, but usually). Some species reproduce asexually, which is, by definition, cloning. Obvious examples of asexual reproduction are amoebas and pea plants.
In the context of genetics, Dolly is a cloned sheep, as well as the first mammal to be cloned. Dolly was cloned in Great Britain.
2. When a zygote divides into to separate cells, it is called Artificial Embryo Twinning.
3. Somatic cells are also called: adult cells.
4. In order to clone a gene, a gene is inserted into a strand of DNA, usually a plasmid.
5. In order to create an embryo from a somatic cell, the donor egg cell must have its nucleus removed.
Click and Clone
6. List all the materials needed to clone a mouse.
- DNA from the mouse to be cloned
- A surrogate mother mouse
- Sharp pipette
- Blunt pipette
- A chemical to stimulate cell division
- Petri dishes
- Microscope
7. Place the following steps in the correct order.
a) Isolate all of the donor cells
b) Remove and discard the nucleus from the egg cell
c) Transfer the somatic cell nucleus into the egg cell
d) Stimulate cell division
e) Implant embryo into a surrogate mother
f) Deliver baby
9. What color with (sic) the cloned mouse be? Brown. What is the name of this mouse? Mimi.
Why Clone?
10. Why is cloning extinct animals problematic? Locating the DNA of an extinct species is very difficult.
11. What are some reasons a person might want to clone a human? To allow infertile couples to have "children" and to replace deceased children (although the latter seems awfully questionable).
The Clone Zone
12. What animal was cloned in 1885? The sea urchin.
13. How did Spemann separate the two cells of the embryo of a salamander in 1902? The embryo was split with a baby's hair.
14. The process of removing a nucleus is called enucleation.
15. In 1952, the nucleus of a frog embryo cell was placed into a donor cell. Did it work to clone the animal? No.
16. Can the nucleus of an adult cell be injected into an egg cell and produce a clone? Yes.
17. Why are mammals hard to clone? Their DNA is complex, and their development is largely based on their environment.
18. What were the names of the first two cloned cows? Fusion and Copy.
19. In what year was the National Bioethics Advisory Council formed? 1995
20. The first mammal clone to be produced from an adult (somatic) cell? (sic) Dolly.
21. What do scientists do to adult cells to make them "behave" like embryos? The electric shock technique simulates fertilization by sperm, causing the cell to divide.
22. Transgenic, cloned sheep were used to produce what medical protein? Factor IX
23. What is a stem cell? An undifferentiated cell whose daughter cells may differentiate into other types of cells.
Cloning Myths
24. Briefly describe in your own words, (sic) why CC the cat was not identical in color to Rainbow, even though she was a clone?
Very early in her development, each of Rainbow's cells "turned off" one entire X chromosome - thus turning off either the black color gene or the orange one. In short, the genes are identical, but they are expressed differently.
25. What is "nature vs nurture"?
Nature vs. nurture is the supposed conflict between genetics and parenting: a continuing and stagnant argument over whether or not parenting has a significant influence on the child.
Is it Cloning or Not?
26. For each of the following scenarios, indicate YES (it is cloning) or NO (it is not cloning)
(NO)Sperm taken from a mole goat is combined with a female's egg in a petri dish. The resulting embryo is implanted into the female's uterus to develop
(YES)A sheep embryo, composed of 16 cells, is removed from the mother's uterus and separated into individual cells. Each cell is allowed to multiply, creating 16 separate embryos, which are then implanted in different female sheep to develop to maturity.
(NO)A cow with many desirable traits is stimulated with hormones to produce a number of egg cells. Each of these eggs is fertilized and implanted into a surrogate mother.
(NO) In vitro fertilization
(YES) Cell nuclei from an extinct wolly mammoth are placed into enucleated cow cells.
27. Define or describe each of the following processes (you may need to reset the Cloning or Not Screen)
In vitro fertilization
Fertilization of an embryo by sperm cells within a test tube.
Embryo splitting
An embryo splitting evenly, causing the development of two identical organisms.
Somatic Cell Nuclear Transfer
Creating a clonal embryo using an ovum with a donor nucleus.
Multiple Ovulation Embryo Transfer
A process to produce multiple copies of an animal.
Artificial Insemination
Sperm is placed into a female reproductive track in an attempt to cause fertilization.
What Are the Risks of Cloning?
28. What is one reason why cloning animals has such a high failure rate?
Pregnancy frequently fails.
29. What is a telomere and how does it affect cloned animals?
A telomere is "junk DNA" at the beginning and end of each chromosome.
30. Pick one of the questions to ponder and ....ponder it. Write a brief essay on your thoughts and opinions.
If a clone originates from an existing person, who is the parent?
The term "parent" is a pretty meaningless when applied to artificially produced organisms. After referring to a number of different dictionaries, there appears to be two definitions of "parent": the more common one is "the person who raises a child," which seems pretty self explanatory. The second definition is "one of the two organisms from whom one is immediately biologically descended," but in this case there would only be one person: the organism which is cloned is, by definition, a clone of itself. Obviously refutable paradoxes in the English language are such fun!
In other words, there are two different kinds of parents: biological and social. Biological parents are the entities from which an organism descends. Most organisms only have biological parents; they are not raised, and learn to survive on their own (i.e. spawning salmon). Social parents are organisms which raise a child (not necessarily their own, but usually). Some species reproduce asexually, which is, by definition, cloning. Obvious examples of asexual reproduction are amoebas and pea plants.
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