After reading the article, "The 20 big questions in science," I was most interested in the question, about time travel. It interests me because scientist actually have a hypothesis for time travel, when I had always heard that time travel was impossible. Their hypothesis involves them using spaceships and wormholes.
The following are my big 20 questions.
1. Do all people seem the same colors the same way? (Ex: Is my red the same as your blue?)
2. What happens when you die?
3. Is there a limit to how big the universe can get?
4. What was there before the big bang?
5. What is the smallest thing that makes up other things? (Ex: What are protons made of? What are those things made of? Etc.)
6. Why does your voice sound different in a recording?
7. What is the fourth dimension?
8. Why did humans evolve to be the dominant species on the Earth, and not another species, or why not multiple species?
9. How would the Grandfather Paradox affect the world if time travel was possible?
10. Why can nothing go faster than the speed of light?
11. What would happen if electrons didn't repel each other, and we could actually touch things?
12. Is there anything completely random? (Ex: If watched closely enough, and all surrounding conditions are known, then a dice toss could be predicted.)
13. Do animals other than humans have feelings?
14. Is there a maximum limit to how hot something can get?
15. What will happen to something when it reaches 0 kelvin?
16. How much is the Earth worth in the US Dollar, ignoring supply and demand, just counting resources, location, and size?
17. How many protons can an atom have?
18. Could the Banach-Tarski Paradox ever be applied to anything in the real world?
19. At what point during evolution is a species defined as a different species than its predecessors?
20. Is there anything other than matter and energy in the universe?
Monday, September 28, 2015
Identifying Questions and Hypotheses
Scientists in the University of Pittsburgh grew human heart tissue out of human stem cells that contracted in a petri dish. They used induced pluripotent stem cells (iPS) from human skin cells. iPS cells can be made to become any cell in the body. After being placed on a non-living "scaffold" of mouse heart cells. It developed into a heart muscle, and after 20 days of blood supply, it began contracting. The experiment was done to help repair damaged cells in the human body. They hypothesized that iPS cells would work just as well as stem cells from an embryo. Previous knowledge they had was how stem cells work from human embryos.
http://news.discovery.com/tech/biotechnology/stem-cells-grow-beating-heart-130814.htm
Monday, September 21, 2015
Unit 2 Reflection
Unit 2 was titled miniature biology. It was about atoms, water, and the four macro-molecules, lipids, nucleic acid, proteins, and carbohydrates, with extra focus on a type of protein called an enzyme.
Atoms are the smallest unit of matter that can't be divided into smaller pieces. Atoms are made of protons, which have a positive charge, and neutrons, which have a neutral charge, in the nucleus, and electrons, which have a negative charge, circling around the nucleus. The number of protons and electrons are always the same in an atom. The number of neutrons can change, but the element will still have the same chemical properties and be called an isotope. Elements are pure substances made of only one type of atom. Atoms can bond together in several ways. 3 of the bonds are ionic, covalent, and hydrogen. Ionic bonds are when one atom gives an electron to another atom, creating a positive ion (the atom that gave the electron) and a negative ion (the atom that received the electron) which are attracted together. Covalent bonds are when 2 atoms share electrons. The electrons circle around both atoms, but tend to stay more towards the atom with more protons because it has a more positive charge, which attracts the negative electrons. This causes an molecule to be polar, where one part is more negatively charged, and another part of the molecule is more positively charged. An example of this is water, where the oxygen is more negatively charged, and the hydrogen atoms are more positively charged. In water, hydrogen bonds can form where two oppositely charged part of polar molecules have a weak attraction towards each other. When atoms react, they bond to form a new substance which has completely different chemical properties than the original atoms that it came from.
Water, as previously mentioned, is a polar molecule, with a negative oxygen atom, and two positive hydrogen atoms. This makes water cohesive, which causes it to hydrogen bond to itself and stick together, which causes water to bead up in dew. It is also adhesive, which makes it hydrogen bond to other surfaces, like a meniscus on a graduated cylinder. When both adhesion and cohesion are combined in a small enough area, it causes capillary action, which can make water flow up against the pull of gravity. Water is known as the universal solvent, because it can dissolve many things. Substances that dissolve things are called solvents, and the things that are dissolved are called solutes. Everything has a pH, which is its level of acidity. If something has a pH of 7, it is neutral. If it is above 7 to a maximum of 14, it is basic. If it is below seven to a minimum of 1, it is acidic. Acids are sour, corrosive to metal, and have more positive H+ (hydrogen) ions than negative OH- (hydroxide) ions. Bases are bitter, and have more OH- ions than H+ ions. When if either an acid or a base is combine with the opposite, it becomes less basic or less acidic.
The four macro molecules are lipids, proteins, nucleic acid, and carbohydrates. All macro-molecules are made of carbon, which has the ability to bond with itself. Carbohydrates are made up of one or more rings of carbon, hydrogen, and carbon. They are used to store energy in animals, and make up the structure of plants. When a carbohydrate is made of only one ring, it is a monosaccharide, like fructose. When it is made of 2 or more rings, it is a disaccharide, like lactose. When it is made of 3 or more rings, it is a polysaccharide, like starch. Monosaccharides and polysaccharides taste sweet, and polysaccharides don't. Proteins are made of a combination of 20 total amino acids. They have several levels of structure. First in the primary structure, which is the amino acids bonding together. Multiple amino acids bonded together are polypeptides. The next level is the Secondary structure. The bonded amino acids hydrogen bond together to form a helix. Next is the Tertiary structure, where the amino acid bonds cause folding. Then the last level is the Quaternary Structure, where multiple tertiary structures bond to make a large protein.
Atoms are the smallest unit of matter that can't be divided into smaller pieces. Atoms are made of protons, which have a positive charge, and neutrons, which have a neutral charge, in the nucleus, and electrons, which have a negative charge, circling around the nucleus. The number of protons and electrons are always the same in an atom. The number of neutrons can change, but the element will still have the same chemical properties and be called an isotope. Elements are pure substances made of only one type of atom. Atoms can bond together in several ways. 3 of the bonds are ionic, covalent, and hydrogen. Ionic bonds are when one atom gives an electron to another atom, creating a positive ion (the atom that gave the electron) and a negative ion (the atom that received the electron) which are attracted together. Covalent bonds are when 2 atoms share electrons. The electrons circle around both atoms, but tend to stay more towards the atom with more protons because it has a more positive charge, which attracts the negative electrons. This causes an molecule to be polar, where one part is more negatively charged, and another part of the molecule is more positively charged. An example of this is water, where the oxygen is more negatively charged, and the hydrogen atoms are more positively charged. In water, hydrogen bonds can form where two oppositely charged part of polar molecules have a weak attraction towards each other. When atoms react, they bond to form a new substance which has completely different chemical properties than the original atoms that it came from.
Water, as previously mentioned, is a polar molecule, with a negative oxygen atom, and two positive hydrogen atoms. This makes water cohesive, which causes it to hydrogen bond to itself and stick together, which causes water to bead up in dew. It is also adhesive, which makes it hydrogen bond to other surfaces, like a meniscus on a graduated cylinder. When both adhesion and cohesion are combined in a small enough area, it causes capillary action, which can make water flow up against the pull of gravity. Water is known as the universal solvent, because it can dissolve many things. Substances that dissolve things are called solvents, and the things that are dissolved are called solutes. Everything has a pH, which is its level of acidity. If something has a pH of 7, it is neutral. If it is above 7 to a maximum of 14, it is basic. If it is below seven to a minimum of 1, it is acidic. Acids are sour, corrosive to metal, and have more positive H+ (hydrogen) ions than negative OH- (hydroxide) ions. Bases are bitter, and have more OH- ions than H+ ions. When if either an acid or a base is combine with the opposite, it becomes less basic or less acidic.
The four macro molecules are lipids, proteins, nucleic acid, and carbohydrates. All macro-molecules are made of carbon, which has the ability to bond with itself. Carbohydrates are made up of one or more rings of carbon, hydrogen, and carbon. They are used to store energy in animals, and make up the structure of plants. When a carbohydrate is made of only one ring, it is a monosaccharide, like fructose. When it is made of 2 or more rings, it is a disaccharide, like lactose. When it is made of 3 or more rings, it is a polysaccharide, like starch. Monosaccharides and polysaccharides taste sweet, and polysaccharides don't. Proteins are made of a combination of 20 total amino acids. They have several levels of structure. First in the primary structure, which is the amino acids bonding together. Multiple amino acids bonded together are polypeptides. The next level is the Secondary structure. The bonded amino acids hydrogen bond together to form a helix. Next is the Tertiary structure, where the amino acid bonds cause folding. Then the last level is the Quaternary Structure, where multiple tertiary structures bond to make a large protein.
Friday, September 18, 2015
Cheese Lab Conclusion
In this lab we asked what the optimal conditions and curdling agents for making cheese are. Out hypothesis was supported when we found that Chymosin in a hot, acidic, environment was the fastest. We tested Chymosin, Rennin, and buttermilk curdling agents in milk, as well as plain milk as a control, in basic, acidic, neutral, hot, cold, and warm environments separately. The buttermilk and plain milk did not curdle the milk at all. Neither Chymosin nor Rennin curdled the milk in cold or basic temperatures, but curdled it in all other conditions. With an acid, both curdled the milk in about 5 minutes, but when tested in a neutral environment, Rennin curdled the milk in 10 minutes and the Chymosin took 15 minutes. When tested warm environment, they both curdled in about 15 minutes. In the hot environment, it took 5 minutes for the Chymosin to curdle the milk and 10 minutes for the Rennin to curdle it. They both performed equally well in an acidic environment and a warm environment, but the Chymosin performed better in the hot environment, and the Rennin performed better in the neutral pH environment. Because hot, acidic, environments appear to be most favorable for curdling milk, the Chymosin performed better due to its faster time in the hot environment.
Although out hypothesis was supported, there may have been errors. We only checked for curdling every 5 minutes, so some curdling agents may have caused curdling earlier than others, but no one checked it then, leading to imprecise data. Another factor that may have caused error was having the different curdling agents being tested in the hot environment in one place. While checking for curdling, I accidentally checked a different curdling agent once, which led to confusion and basing the data off of a different independent variable. To fix theses errors, we could check the curdling agents more often, perhaps once every minute, and more label the samples with group names in addition to what factor they are testing.
This lab was done to demonstrate the effect of different pH and temperature on enzymes. From this lab I learned that some enzymes perform more effectively with different substrates in different conditions, which helps me understand what causes enzymes to denature and what causes them to work more efficiently. Based on my experience from this lab, I could more easily find optimal conditions for enzymes to speed up other reactions that may have a high activation energy or take a long time to perform naturally.
Although out hypothesis was supported, there may have been errors. We only checked for curdling every 5 minutes, so some curdling agents may have caused curdling earlier than others, but no one checked it then, leading to imprecise data. Another factor that may have caused error was having the different curdling agents being tested in the hot environment in one place. While checking for curdling, I accidentally checked a different curdling agent once, which led to confusion and basing the data off of a different independent variable. To fix theses errors, we could check the curdling agents more often, perhaps once every minute, and more label the samples with group names in addition to what factor they are testing.
This lab was done to demonstrate the effect of different pH and temperature on enzymes. From this lab I learned that some enzymes perform more effectively with different substrates in different conditions, which helps me understand what causes enzymes to denature and what causes them to work more efficiently. Based on my experience from this lab, I could more easily find optimal conditions for enzymes to speed up other reactions that may have a high activation energy or take a long time to perform naturally.
| Curdling Agent | Chymosin | Rennin | Buttermilk | Milk (Control) |
| Acid | 5 | 5 | ||
| Base | ||||
| pH Control | 15 | 10 | ||
| Cold | ||||
| Hot | 5 | 10 | ||
| Temp Control | 15 | 15 |
Monday, September 14, 2015
Carbohydrate Sweetness Lab Analysis
In this lab we asked whether there is a difference in taste with monosaccharides, disaccharides, and polysaccharides. Our hypothesis that Galactose, a monosaccharide, would taste sweet was supported by our evidence. Sucrose, Glucose, Fructose, Galactose, and Maltose all tasted sweet. This is because they are all either monosaccharides or disaccharides, which taste sweeter than polysaccharides. Specifically Galactose is a monosaccharide.
While our hypothesis was supported by our data, there could have been possible errors due to rushed and unequal sampling, the lack of both a positive and negative control, and different perceptions of sweetness. While tasting some of the last samples we tried, Lactose, Starch, and Cellulose, we were hurrying to finish with the rest of the class. This and taking different sized samples could have resulted in some larger samples tasting sweeter than smaller samples, and poor observations for the later carbohydrates we tried. While we had a control, it wasn't positive or negative, it was a rating of 100 to base the other samples off of. This means that we didn't know how sweet something that would be rated 200 would taste, or something rated 0. Different perceptions of sweetness may have also affected our data. People can perceive sweetness differently due to several factors such as age, type of food previously eaten, how hungry you are, if you smoke, if you are obese, if you are pregnant, sickness or disease, and temperature of food. Several of these factors don't apply to this situation, such as age, which isn't a factor until around 45, smoking, because neither of us smoke, pregnancy, because we are both males, sickness, because neither of us were sick, and temperature of food, because the food was the same temperature for both of us. But having just finished lunch, hunger and food previously eaten may have been a factor in affecting out sense of taste. .In future experiments, I recommend moving at a faster pace throughout the entire lab, but not rushing to finish, and also adding a positive and negative control to more accurately rate samples. Unfortunately, nothing can be done about eating before doing this because the class is always after lunch.
This lab was done to demonstrate how monosaccharides, disaccharides, and polysaccharides, while all made of the same elements, have different flavors. From this lab I learned that all carbohydrates have different properties, which helps me understand how they are used differently in plants, animals, and food production. Based on my experience from this lab, I will better understand what is in my food and how healthy it is, for example, fructose tastes very sweet and is also unhealthy.
While our hypothesis was supported by our data, there could have been possible errors due to rushed and unequal sampling, the lack of both a positive and negative control, and different perceptions of sweetness. While tasting some of the last samples we tried, Lactose, Starch, and Cellulose, we were hurrying to finish with the rest of the class. This and taking different sized samples could have resulted in some larger samples tasting sweeter than smaller samples, and poor observations for the later carbohydrates we tried. While we had a control, it wasn't positive or negative, it was a rating of 100 to base the other samples off of. This means that we didn't know how sweet something that would be rated 200 would taste, or something rated 0. Different perceptions of sweetness may have also affected our data. People can perceive sweetness differently due to several factors such as age, type of food previously eaten, how hungry you are, if you smoke, if you are obese, if you are pregnant, sickness or disease, and temperature of food. Several of these factors don't apply to this situation, such as age, which isn't a factor until around 45, smoking, because neither of us smoke, pregnancy, because we are both males, sickness, because neither of us were sick, and temperature of food, because the food was the same temperature for both of us. But having just finished lunch, hunger and food previously eaten may have been a factor in affecting out sense of taste. .In future experiments, I recommend moving at a faster pace throughout the entire lab, but not rushing to finish, and also adding a positive and negative control to more accurately rate samples. Unfortunately, nothing can be done about eating before doing this because the class is always after lunch.
This lab was done to demonstrate how monosaccharides, disaccharides, and polysaccharides, while all made of the same elements, have different flavors. From this lab I learned that all carbohydrates have different properties, which helps me understand how they are used differently in plants, animals, and food production. Based on my experience from this lab, I will better understand what is in my food and how healthy it is, for example, fructose tastes very sweet and is also unhealthy.
Carbohydrate
|
Type of Carbohydrate
|
Degree of Sweetness (0 to 200)
|
Sucrose
|
Disaccharide
|
100
|
Glucose
|
Monosaccharide
|
120
|
Fructose
|
Monosaccharide
|
150
|
Galactose
|
Monosaccharide
|
70
|
Maltose
|
Disaccharide
|
60
|
Lactose
|
Disaccharide
|
20
|
Starch
|
Polysaccharide
|
0
|
Cellulose
|
Polysaccharide
|
0
|
 |
| Galactose, pictured in the center, is a monosaccharide. |
Friday, September 4, 2015
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