1. What is your ecological footprint? (That is, if everyone lived like you, how many earths would it take to support the world population?)
My ecological footprint if everyone lived like me would be 5.01 earths.
2. As the world population grows, how will this impact the amount of resources (food, electricity, water, etc.) each person can consume and still remain within the sustainability of our planet? That is, what lifestyle changes will we need to make in order to ensure there is enough food and energy to sustain everyone?
3. What is the IPCC? What does it do?
The IPCC is the worlds leading authority on the science of climate change. They document the causes of global warming, which countries and which ecosystems are most affected. The IPCC also makes sure that policy makers know what they need to do to keep warming at or below the critical two-degree threshold.
4. Which climates require the most energy and the least energy on average to live in? (Give an example of a country for each)
The climates that require the most energy are coller climates such as Siberia because they need lots of heat for lighting and for cooking. The climates that require the least energy are hot and humid climates like Phoenix, Arizona, although there is still energy required for cooling as well as refrigeration it is not as bad as the cooler climates.
5. What is the Climate Action Network? What does it do?
The Climate Action Network is a worldwide network of over 265 non governmental organizations. The CAN works to promote government and individual action to mimit human-induced climate change to ecologically substainable levels. The members of CAN work to achieve this particular goal through the coordination of information exchange and NGO strategy on international, regional and national climate issues.
6. How do energy efficient appliances, line-drying your clothes, and using compact fluorescent light bulbs each help to reduce carbon emissions?
Energy efficient appliances help to reduce carbon emissions by using 2 to 10 times less energy. Line drying clothes instead of using a dryer saves 3 to 4 kilowatt hours per load-which equals out to about 5 pounds of carbon dioxide. Using compact flourescent bulbs instead of incandescent bulbs use four times less energy and last eight times longer.
7. Why are compact urban living and rural living more energy efficient than sprawling suburbs?
Compact urban living and rural living is more energy efficient than sprawling suburbs because carbon emissions are generally highest for households living in newer suburbs and because spread out suburbs require far more energy per person for public infrastructure.
8. What are carbon offsets?
Carbon offsets help consumers reduce their carbon footprint and make you, your car and your entire household carbon neutral.
9. Why does eating meat require more energy than eating plants?
Eating meat requires more energy than eating plants because a plant-based diet is significantly less land and energy intensive than a diet with a high proportion of meat, seafood, and dairy. Meat production also drives deforestation and requires high inputs of energy for processing and transportation.
10. How do food miles and food processing and packaging play a role in a person’s ecological footprint? How do personal and community gardens help alleviate this?
Food miles and food processing and packaging play a role in a person's ecological footprint because if your food comes from far away it requires alot of energy for transportation and refrigeration. If the food is hightly processed and comes in copious paper it puts a strain on forests. Personal and community gardens help relieve the enormous enviornmental impacts associated with industrial agriculture. Also, studies show that home or community gardening can add $500 to $1,200 worth of produce per year to a familys diet which is of great help to low income families.
11. What is a “food footprint?” What is a “housing footprint?”
A "food footprint" is the area needed to grow crops, fish and graze animals as well as carbon emissions from food processing and transport. A "housing footprint" is the area occupied by your home and the area needed to supply resources used in construction and household maintenance.
12. What construction and design features contribute to green buildings?
The type of construction and design features that contribute to green buildings are passive solar heating, water efficient fixtures, and recycled materials.
13. Finish the following statement: Energy is required to _deliver_ and __treat__fresh water. We can reduce our water footprint by ___60%___ and ____more____.
14. Describe two benefits of “green” cleaning products.
One benefit is that they are not harmful to humans another would be that they don't contaminate water supplies.
15. What is planned obsolescence? How can we counter it?
Planned obsolescence is the deliberate manufacturing of products to wear out quickly. We can counter it by trying to repair things as mjuch as possible and oly buying products that are designed to last.
16. What are the five environmental and economic benefits of recycling?
1. Reduced landfill space
2. Fewer demands on raw materials
3. Less energy consumption
4. Less air & water pollution
5. Cheaper goods & lower waste disposal bills
17. Click the “Reduce your footprint” link at the end of the survey and write a one-paragraph plan for how you intend to reduce your footprint. Your plan should include a list of behaviors you are committed to changing. Ideally, I would like you to select at least one behavior from each of the seven categories on the “Reduce your footprint” page that you are going to work on.
I intend to reduce my carbon footprint by walking more instead of driving my car, especially when around my neighborhood. Another way that I want to reduce my footprint is by installing compact flourescent light bulbs around my familys home, and when I own my own house I plan to choose energy efficient appliances. A couple of years ago I used to go to many local farmers markets as well as buy organic fruits and vegetables. I plan on doing this once again and changing my diet to a more fruits and vegetable consumption, rather than meat. Using bio-degradable as well as non-toxic cleaning products instead of harmful ones will also be a new goal of mine. I pledge to take shorter showers and only wash full loads of clothes and air dry my clothes afterwards on a clothes line instead of a dryer. I will recycle everything I can recycle, but waste less and buy less things that I do not need.
Friday, May 14, 2010
Saturday, May 1, 2010
Blog Assignment #8: Part Two Scientific Article Summaries
Scientific Article #2: Why you can read this-and Why the Chimp can't. . .
Research has proved that humans and chimpanzees have many gene similarities but one of the major differences between the two is how often genes switch on and off. It is stated that the two species are about 98.7 percent identical; however after measuring the activity of nearly 18,000 genes shared among the species the number of genes and proteins they expressed differed. The difference was at least five times more apparent between humans than among the other species in the study. Scientists concluded that sometime in the recent evolutionary past, changes in the gene expression must have been accelerated in the human brain. This acceleration it seems, is the key difference between humans and chimpanzees.
Research has proved that humans and chimpanzees have many gene similarities but one of the major differences between the two is how often genes switch on and off. It is stated that the two species are about 98.7 percent identical; however after measuring the activity of nearly 18,000 genes shared among the species the number of genes and proteins they expressed differed. The difference was at least five times more apparent between humans than among the other species in the study. Scientists concluded that sometime in the recent evolutionary past, changes in the gene expression must have been accelerated in the human brain. This acceleration it seems, is the key difference between humans and chimpanzees.
Blog Assignment #8: Part Two Scientific Article Summaries
Scientific Article #1: Human Chimps not as Closely Related as Thought?
In the mid 1970's researchers at the University of Berkley discovered a genetic similarity between humans and chimpanzees, finding out that they were 99% identical. Modern research that uses more sophisticated methods found that the discoveries of the 1970's might not be as accurate as we once thought. Scientists now agree that the two species technically only share 95% of genetic material. Regardless of the now updated data human beings cannot deny the close relation man has to the chimpanzee. This 5% is probably closer to what people thought the difference would ultimately be, and despite the genetic differences between chimpanzees and humans- the chimpanzee does not seem to suffer the same diseases that regularly affect people. For scientists studying the genetic differences between these two species may possibly provide more insight on these diseases and guide us to future cures.
In the mid 1970's researchers at the University of Berkley discovered a genetic similarity between humans and chimpanzees, finding out that they were 99% identical. Modern research that uses more sophisticated methods found that the discoveries of the 1970's might not be as accurate as we once thought. Scientists now agree that the two species technically only share 95% of genetic material. Regardless of the now updated data human beings cannot deny the close relation man has to the chimpanzee. This 5% is probably closer to what people thought the difference would ultimately be, and despite the genetic differences between chimpanzees and humans- the chimpanzee does not seem to suffer the same diseases that regularly affect people. For scientists studying the genetic differences between these two species may possibly provide more insight on these diseases and guide us to future cures.
Blog Assignment #8: (Part 1 of 6 posts) Part 6 Human's: Riddle of the Bones
Human's: Riddle of the Bones
1. What is "Lucy" and how did it get it's name?
"Lucy" is a preserved fossil of female bones found in east Africa that is almost 3.2 million years old. "Lucy" got its name from the Beatles song "Lucy in the Sky with Diamonds" the song that was playing when she was discovered in 1974.
2. Which hominid species does this activity focus on?
The hominid species that this activity focused on was A. afarensis.
3. Why do scientists believe these species all belong to the same family?
The reason that scientists believe that these species could have all belonged to the same family was because of the wide range in body size. This led them to also suspect that they were all from the same "extended family" of 13 individuals which ended up being entomed together in a flash flood disaster. There had most likely been 9 adults and 4 children judging from their teech and jaws, but they were certainly all from the same species. The difference in the size of Lucy's petite bones and the more robust bones found at Hadar puzzled paleoanthropologists but upon further research of thousands of fossils they concluded that the males had most likely been more tall and blukier than the females, similar to present day gorillas.
4. How old is each set of fossils show in this activity?
The First Family fossil set was 3.2 million years old, Lucy was 3.2 million years old as well, the Hadar Skull was 3.0 million years old & the Laetoli Footprints were 3.6 million years old.
5. Based on the description of each set of bones and the footprints, did this species live in trees or on land? Explain and defend your answer by referencing the evidence in your explanation.
Based on the description of each set of bones and footprints I conclude that this species lived on land. The reason behind my conclusion is that the evidence provided states that the first set of heel bones were able to withstand pressure of walking upright. Like the modern heels of a human being they were filled with shock absorbing "spongy" bone rather than the more solid bone found in the heels of apes. Toe bones that were also found among the first family indicate that they don't curve forward towards the heel as do the toes of modern tree climbing primates. Another piece of evidence was Lucy's pelvis which hints that she walked upright on two legs, the pelvis looking much like that of a modern woman's pelvis which helped support her upper body as she moved.
6. How did males and females of this species differ?
Males and females of this species differed because the males were much more robust and taller than the females. Just like modern gorillas the males towered over the females.
7. How did the brains of this species compare to modern humans? What evidence supports this?
The brains of this species were small-brained compared to modern humans because of the cavity at the back of the skull evidence states that they only had chimp sized brains.
1. What is "Lucy" and how did it get it's name?
"Lucy" is a preserved fossil of female bones found in east Africa that is almost 3.2 million years old. "Lucy" got its name from the Beatles song "Lucy in the Sky with Diamonds" the song that was playing when she was discovered in 1974.
2. Which hominid species does this activity focus on?
The hominid species that this activity focused on was A. afarensis.
3. Why do scientists believe these species all belong to the same family?
The reason that scientists believe that these species could have all belonged to the same family was because of the wide range in body size. This led them to also suspect that they were all from the same "extended family" of 13 individuals which ended up being entomed together in a flash flood disaster. There had most likely been 9 adults and 4 children judging from their teech and jaws, but they were certainly all from the same species. The difference in the size of Lucy's petite bones and the more robust bones found at Hadar puzzled paleoanthropologists but upon further research of thousands of fossils they concluded that the males had most likely been more tall and blukier than the females, similar to present day gorillas.
4. How old is each set of fossils show in this activity?
The First Family fossil set was 3.2 million years old, Lucy was 3.2 million years old as well, the Hadar Skull was 3.0 million years old & the Laetoli Footprints were 3.6 million years old.
5. Based on the description of each set of bones and the footprints, did this species live in trees or on land? Explain and defend your answer by referencing the evidence in your explanation.
Based on the description of each set of bones and footprints I conclude that this species lived on land. The reason behind my conclusion is that the evidence provided states that the first set of heel bones were able to withstand pressure of walking upright. Like the modern heels of a human being they were filled with shock absorbing "spongy" bone rather than the more solid bone found in the heels of apes. Toe bones that were also found among the first family indicate that they don't curve forward towards the heel as do the toes of modern tree climbing primates. Another piece of evidence was Lucy's pelvis which hints that she walked upright on two legs, the pelvis looking much like that of a modern woman's pelvis which helped support her upper body as she moved.
6. How did males and females of this species differ?
Males and females of this species differed because the males were much more robust and taller than the females. Just like modern gorillas the males towered over the females.
7. How did the brains of this species compare to modern humans? What evidence supports this?
The brains of this species were small-brained compared to modern humans because of the cavity at the back of the skull evidence states that they only had chimp sized brains.
Wednesday, April 28, 2010
Blog Assignment#8: (Part 1 of 6 posts) Part 5 Humans: Babies by Design
Babies by Design
My belief is that we should be able in the near future create "babies by design", meaning that we would be able to scientifically alter our future childrens genes. The reason behind my choice is due to the fact that there are many babies/human beings born into this world that have genetic diseases or that have terrible disabilities that make it difficult for them to function in our everyday society. If we were to be able to create "babies by design" we would ultimatley be able to eliminate our future generations from having any of these genetic diseases or disabilities. It is already quite difficult to bring another life into this world, but to find out that your baby had a disease that would inevitably lead to death would be devestating to any parent. An example of such a terrible disease would be one such as PKU. PKU is a disease that is caused by the lack of a liver enzyme that is needed to break down the amino acid phenylalanine, there is nothing that can be done to prevent death and the child ends up dying quickly. I believe that in the near future we will be able to prevent such devetating results if we keep researching and opening up our minds to the possibility that we can somehow play god.
My belief is that we should be able in the near future create "babies by design", meaning that we would be able to scientifically alter our future childrens genes. The reason behind my choice is due to the fact that there are many babies/human beings born into this world that have genetic diseases or that have terrible disabilities that make it difficult for them to function in our everyday society. If we were to be able to create "babies by design" we would ultimatley be able to eliminate our future generations from having any of these genetic diseases or disabilities. It is already quite difficult to bring another life into this world, but to find out that your baby had a disease that would inevitably lead to death would be devestating to any parent. An example of such a terrible disease would be one such as PKU. PKU is a disease that is caused by the lack of a liver enzyme that is needed to break down the amino acid phenylalanine, there is nothing that can be done to prevent death and the child ends up dying quickly. I believe that in the near future we will be able to prevent such devetating results if we keep researching and opening up our minds to the possibility that we can somehow play god.
Blog Assignment #8: (Part 1 of 6 posts) Part 4 Humans:Origins of Humankind
Humans: Origins of Humankind
The list of species that lead to humans:
1. Orrorin tugensis
2. Australopithecus anamensis
3. Kenyanthropus platyops
4. Homo habilis
5. Homo erectus
6. Homo sapiens
The list of species that lead to humans:
1. Orrorin tugensis
2. Australopithecus anamensis
3. Kenyanthropus platyops
4. Homo habilis
5. Homo erectus
6. Homo sapiens
Blog Assignment #8: (Part 1 of 6 posts) Part 3 Survival: Microbe Clock
Survival: Microbe Clock
A) Describe in detail how Streptococcus pneumoniae has developed antibiotic resistance over the past century.
Streptococcus pneumonia has developed resistance over the past century by developing strains which have evolved resistance. Streptococcus has become completely resistant to penicillin and the search for alternative antibiotics has been unsucessful. Since the year 1997 Streptococcus has developed resistance to at stockpile of at least 100 drugs. The list of microbes that have developed resistance is growing quickly.
B) Start the clock. The one minute of division here represents 186 days of actual division. How many times did the cells divide in this time? How many total cells resulted at the end of this time? How many mutations occcurred in the population during this time?
The cells that divided were a total of 313,807, the total number of cells were 13,274, the total number of mutations that occurred were 1,314
A) Describe in detail how Streptococcus pneumoniae has developed antibiotic resistance over the past century.
Streptococcus pneumonia has developed resistance over the past century by developing strains which have evolved resistance. Streptococcus has become completely resistant to penicillin and the search for alternative antibiotics has been unsucessful. Since the year 1997 Streptococcus has developed resistance to at stockpile of at least 100 drugs. The list of microbes that have developed resistance is growing quickly.
B) Start the clock. The one minute of division here represents 186 days of actual division. How many times did the cells divide in this time? How many total cells resulted at the end of this time? How many mutations occcurred in the population during this time?
The cells that divided were a total of 313,807, the total number of cells were 13,274, the total number of mutations that occurred were 1,314
Blog Assignment #8: (Part 1 of 6 posts) Part 2 Change: Deep Time
Change: Deep Time
1. Atmosphere forms: Precambrian Eon 4,550-543 mya-Hadean 4,500 mya
2. Earth's core forms: Precambrian Eon 4,550-543 mya-Hadean 4,400 mya
3. First living organisms evolve(prokaryotic cells): Precambrian Eon 4,550-543 mya-Hadean 3,850 mya
4.First eukaryotic cells evolve: Precambrian Eon 4,550-543 mya-Archaean 2,700 mya
5. First multicellular organisms evolve(algae): Precambrian Eon 4,550-543 mya-Proterozoic 1,200 mya
6. Ozone layer forms: Precambrian Eon 4,550-543 mya-Proterozoic 600 mya
7. First Chordates evolve (what's a chordate?): Paleozoic Era 543-248 mya-Cambrian 535 mya
A chordate are any of the numerous animals belonging to the the family Chordata having at some stage of development a dorsal nerve cord.
8. First land plants evolve: Paleozoic Era 543-248 mya-Ordovician 480 mya
9. First land animals (bugs) evolve: Paleozoic Era 543-248 mya-Carboniferons 420 mya
10. First land vertebrates evolve (what's a vertebrate?) Paleozoic Era 543-248 mya-Devonian 375 mya
A vertebrate is an animal having a backbone or spinal column.
11. First flowering plants evolved: Paleozoic Era 543-248 mya-Devonian 360 mya
12. First reptiles evolve: Paleozoic Era 543-248 mya-Permian 275 mya
13. Pangaea forms (what is Pangaea?): Paleozoic Era 543-248 mya-Permian 280 mya
The Pangaea is a theory that states that all present continents were once together and collectively known as a "supercontinent" called Pangaea.
14. First mammals evolve: Mesozoic Era 248-65 mya-Triassic 220 mya
15. First birds evolv: Mesozoic Era 248-65 mya-Jurassic 150 mya
16. First primates evolve: Cenozoic Era 65mya-Present Time-Paleocene 60mya
17. Continents reach their present-day formation: Cenozoic Era 65mya-Present-Eocene 40mya
18. First apes evolve from the primate lineage: Cenozoic Era 65mya-Present-Oligocene 25 mya
19. Hominids evolve from the ape lineage (what is a hominid?): Cenozoic Era 65mya-Present-Pliocene 5.2 mya
A hominid is any member of the biological primate family Hominidae.
20. First early humans evolve from the hominid lineage: Cenozoic Era 65mya-Present-Pleistocene 0.16 mya
21. Modern humans evolve from the human lineage: Cenozoic Era 65mya-Present-Pleistocene 0.1 mya
1. Atmosphere forms: Precambrian Eon 4,550-543 mya-Hadean 4,500 mya
2. Earth's core forms: Precambrian Eon 4,550-543 mya-Hadean 4,400 mya
3. First living organisms evolve(prokaryotic cells): Precambrian Eon 4,550-543 mya-Hadean 3,850 mya
4.First eukaryotic cells evolve: Precambrian Eon 4,550-543 mya-Archaean 2,700 mya
5. First multicellular organisms evolve(algae): Precambrian Eon 4,550-543 mya-Proterozoic 1,200 mya
6. Ozone layer forms: Precambrian Eon 4,550-543 mya-Proterozoic 600 mya
7. First Chordates evolve (what's a chordate?): Paleozoic Era 543-248 mya-Cambrian 535 mya
A chordate are any of the numerous animals belonging to the the family Chordata having at some stage of development a dorsal nerve cord.
8. First land plants evolve: Paleozoic Era 543-248 mya-Ordovician 480 mya
9. First land animals (bugs) evolve: Paleozoic Era 543-248 mya-Carboniferons 420 mya
10. First land vertebrates evolve (what's a vertebrate?) Paleozoic Era 543-248 mya-Devonian 375 mya
A vertebrate is an animal having a backbone or spinal column.
11. First flowering plants evolved: Paleozoic Era 543-248 mya-Devonian 360 mya
12. First reptiles evolve: Paleozoic Era 543-248 mya-Permian 275 mya
13. Pangaea forms (what is Pangaea?): Paleozoic Era 543-248 mya-Permian 280 mya
The Pangaea is a theory that states that all present continents were once together and collectively known as a "supercontinent" called Pangaea.
14. First mammals evolve: Mesozoic Era 248-65 mya-Triassic 220 mya
15. First birds evolv: Mesozoic Era 248-65 mya-Jurassic 150 mya
16. First primates evolve: Cenozoic Era 65mya-Present Time-Paleocene 60mya
17. Continents reach their present-day formation: Cenozoic Era 65mya-Present-Eocene 40mya
18. First apes evolve from the primate lineage: Cenozoic Era 65mya-Present-Oligocene 25 mya
19. Hominids evolve from the ape lineage (what is a hominid?): Cenozoic Era 65mya-Present-Pliocene 5.2 mya
A hominid is any member of the biological primate family Hominidae.
20. First early humans evolve from the hominid lineage: Cenozoic Era 65mya-Present-Pleistocene 0.16 mya
21. Modern humans evolve from the human lineage: Cenozoic Era 65mya-Present-Pleistocene 0.1 mya
Blog Assignment# 8: (Part 1 of 6 posts) Part 1 Darwin: An Origin of Species activity
Darwin: An Origin of Species activity
Enviornmental changes led to the speciation among the Pollenpeeper birds began with a hurrican that struck the Mainland Island in 5mya which reduced the Pollenpeeper's population by 10%. An example of Pollenpeeper's speciation because of enviornment can be taken from the remaining Pollenpeeper's that were left on Mainland Island within the timeline of 5mya to present.
5mya: About 12,000 Pollenpeeper's remain on the Mainland Island while 300 Pollenpeeper's have been scattered troughout the several offshore Islands. These offshore islands are the Nocross Island, Windsor Island & Warwich Archipelago Island.
4mya: The Pollenpeeper's population has fully recovered following the hurrican that hit it in 5mya. The Pollenpeeper's are now expanding their range north & south. The Pollenpeeper population continues to interbreed freely.
3mya: Northern and Southern populations begin to show differences in their appearance due to the interbreeding. Northern birds appear more red in the throat area and the breast area, they also have slightly narrower beaks. This is most likely due to the Northern birds feeding 0n insect larvae.
2mya: The Northern bird population plumage becaomes increasingly red and their beaks have become slightly larger and much more narrow.
1mya: Pollenpeeprs move regularly between the Mainland Island and Windsor Island and the populations between these islands interbreed inhibiting the divergence of the Windsor Island population. This interbreeding results in the offspring having reddish heads of the Windsor birds and the red breasts of the Mainland birds. Feral cats a predator of the Pollenpeeper's are hit hard with an epidemic called "Feline distemper" and decrease in population.
Present Day: Due to the decrease in population of the Feral cats which was a predator to the Pollenpeeper's the population of the birds increases by 15% over several generations. Over the generations a climate change also reduces the availabitlity of grass seeds to the Pollenpeepers which causes the short wide beaks that served well in previous conditions to diminish.
Enviornmental changes led to the speciation among the Pollenpeeper birds began with a hurrican that struck the Mainland Island in 5mya which reduced the Pollenpeeper's population by 10%. An example of Pollenpeeper's speciation because of enviornment can be taken from the remaining Pollenpeeper's that were left on Mainland Island within the timeline of 5mya to present.
5mya: About 12,000 Pollenpeeper's remain on the Mainland Island while 300 Pollenpeeper's have been scattered troughout the several offshore Islands. These offshore islands are the Nocross Island, Windsor Island & Warwich Archipelago Island.
4mya: The Pollenpeeper's population has fully recovered following the hurrican that hit it in 5mya. The Pollenpeeper's are now expanding their range north & south. The Pollenpeeper population continues to interbreed freely.
3mya: Northern and Southern populations begin to show differences in their appearance due to the interbreeding. Northern birds appear more red in the throat area and the breast area, they also have slightly narrower beaks. This is most likely due to the Northern birds feeding 0n insect larvae.
2mya: The Northern bird population plumage becaomes increasingly red and their beaks have become slightly larger and much more narrow.
1mya: Pollenpeeprs move regularly between the Mainland Island and Windsor Island and the populations between these islands interbreed inhibiting the divergence of the Windsor Island population. This interbreeding results in the offspring having reddish heads of the Windsor birds and the red breasts of the Mainland birds. Feral cats a predator of the Pollenpeeper's are hit hard with an epidemic called "Feline distemper" and decrease in population.
Present Day: Due to the decrease in population of the Feral cats which was a predator to the Pollenpeeper's the population of the birds increases by 15% over several generations. Over the generations a climate change also reduces the availabitlity of grass seeds to the Pollenpeepers which causes the short wide beaks that served well in previous conditions to diminish.
Saturday, April 24, 2010
Blog #7: Article Summaries Subjects:Stem Cell & Cloning
http://www.scientificamerican.com/article.cfm?id=cell-induced-pluripotent
Stem Cell: Article ONE
Cell-Off: Induced Pluripotent Stem Cells Fall Short of Potential Found in Embryonic Version
According to scientists Pluripotent stem cells are falling short compared to Embryonic stem cells. It seems that when reprogramming Pluripotent stem cells to attempt to make them as capable as ones from embryos(or, embryonic stem cells) the cells end up resulting aberrant and die abnormally. As a result scientists around the world are currently exploring different techniques for reprogramming mature cells attempting to make them potent.The current progress being made is toward controlled differentiation of the human iPs cell into various tissue types such as 1.heart 2.neuron 3.liver 4. pancreas 5. eye. There is a lot of excitement surrounding iPs cells but noone seems to want to hear the problems surrounding these cells. One issue that scientists discovered was that iPs cells had significantly higher rates of cell death than the embryonic stem cells. IPs cells seem to have a lot of problems but this does not mean that they don't have the potential. All that scientists need is time to work out the issues and they can be very sucessful in the near future. Reading the article I feel that with more extensive research science can advance in the next several years and be able to do proper stem cell research without too many problems.
http://www.scientificamerican.com/blog/post.cfm?id=doctor-attempts-to-clone-people-2009-04-22
Cloning: Article Two
Doctor attempts to clone people
Panayiotis Zavos a doctor who operates a fertility clinic in Kentucky and Cyprus recently told British reporters that he had sucessfully cloned 14 human embryos. Zavos went into further detail claiming that he implanted or transfered 11 of those embryos into the uteruses of four women. None of these embryos resulted in a sucessful pregnancy but Zavos is confident that cloning babies is not far from reach. Scientists are confident that Zavos's claim can become reality because they have been cloning animals using adult cells since the mid 90's. Denny Sakkas says that cloning embryos is one thing but turning those embryos into healthy babies is quite different and more difficult. Sakkas claims that this would mean you would have to wipe the slate clean with respect to "gene expression" in the somatic nucleus, thus reestablishing a new sequence of gene expression. Considerig the many genese involved there is a good chance that a lot could go wrong. After reading this article I have gathered that there is still a lot more that has to be researched as well as tested for cloning to work. There are still many ethical issues that people would also have to deal with and resolve before the cloning of humans would be accepted. The cloning of organs seems to be a good idea because there are not enough people that are willing to donate their body for organ transplants, and this would eliminate much of the wait as well as keep humans living a much longer life.
Stem Cell: Article ONE
Cell-Off: Induced Pluripotent Stem Cells Fall Short of Potential Found in Embryonic Version
According to scientists Pluripotent stem cells are falling short compared to Embryonic stem cells. It seems that when reprogramming Pluripotent stem cells to attempt to make them as capable as ones from embryos(or, embryonic stem cells) the cells end up resulting aberrant and die abnormally. As a result scientists around the world are currently exploring different techniques for reprogramming mature cells attempting to make them potent.The current progress being made is toward controlled differentiation of the human iPs cell into various tissue types such as 1.heart 2.neuron 3.liver 4. pancreas 5. eye. There is a lot of excitement surrounding iPs cells but noone seems to want to hear the problems surrounding these cells. One issue that scientists discovered was that iPs cells had significantly higher rates of cell death than the embryonic stem cells. IPs cells seem to have a lot of problems but this does not mean that they don't have the potential. All that scientists need is time to work out the issues and they can be very sucessful in the near future. Reading the article I feel that with more extensive research science can advance in the next several years and be able to do proper stem cell research without too many problems.
http://www.scientificamerican.com/blog/post.cfm?id=doctor-attempts-to-clone-people-2009-04-22
Cloning: Article Two
Doctor attempts to clone people
Panayiotis Zavos a doctor who operates a fertility clinic in Kentucky and Cyprus recently told British reporters that he had sucessfully cloned 14 human embryos. Zavos went into further detail claiming that he implanted or transfered 11 of those embryos into the uteruses of four women. None of these embryos resulted in a sucessful pregnancy but Zavos is confident that cloning babies is not far from reach. Scientists are confident that Zavos's claim can become reality because they have been cloning animals using adult cells since the mid 90's. Denny Sakkas says that cloning embryos is one thing but turning those embryos into healthy babies is quite different and more difficult. Sakkas claims that this would mean you would have to wipe the slate clean with respect to "gene expression" in the somatic nucleus, thus reestablishing a new sequence of gene expression. Considerig the many genese involved there is a good chance that a lot could go wrong. After reading this article I have gathered that there is still a lot more that has to be researched as well as tested for cloning to work. There are still many ethical issues that people would also have to deal with and resolve before the cloning of humans would be accepted. The cloning of organs seems to be a good idea because there are not enough people that are willing to donate their body for organ transplants, and this would eliminate much of the wait as well as keep humans living a much longer life.
Monday, April 5, 2010
Assignment # 6
Assignment # 6
1.Which regulatory mechanisms occur at the DNA-level, which occur at the protein-level?
Answer: The regulatory mechanisms that occur at the DNA-level are ones that A. prevent mRNA from being transcribed B. involve transcription factors or chromatin remodeling factors.
The regulatory mechanisms that occur at a protein level are ones that A. prevent enzymes from doing their jobs B. involve factors that disable or degrade the enzyme C. are usually controlled by feedback inhibition.
2.How do acetylation, methylation, repressors, activators, and siRNA control gene expression? What role do inducers play?
Answer: Histone "acetylation", DNA "methylation" repressors, activators and siRNA control gene expression through the following: acetylation enable the DNA to be "loose" enough to allow transcription machinery repressors bind to regulatory sites blocking attachment of transcrption factors. Activators bind to regulatory sites associated with a gene. siRNA are "short interfering" RNA that are 20-25 Ribonucleotide-long segments of RNA that bind to mRNA blocking it from being translated into a protein. Inducers function by disabling repressor proteins, thus the repressor proteins bind to the DNA strand and prevent the RNA polymerase from attaching to the DNA and synthesizing mRNA. Inducers bind to repressors which causes them to change shape and prevents them from binding to DNA, therefore allowing transcription followed by gene expression.
3.What is an enhancer and how does it help control how much of a particular protein is made?
Answer: An "enhancer" is a regulatory site from a promoter.
4.How do allosteric inhibition and competitive inhibition differ in the ways they accomplish feedback inhibition?
Answer: To accomplish feedback inhibition allosteric inhibition is very specific and is accomplished only by isoleucine, which binds to a site on the enzyme molecule called the "regulatory", or allosteric site. This site is different from the active site of the enzyme, which is the site of the catalytic action of the enzyme on the substrate. The way that competetive inhibition accomplishes feedback inhibition is that the inhibitor binds ONLY to the free enzyme and CANNOT bind when the substrate is bound.
5.What are the three phases of the cell cycle? What occurs at each phase?
Answer: Interphase, Mitosis, Cytokinesis
Interphase: the phase of the cell cycle in which the cell spends the majority of its time performing the majority of the purposes needed which include: the preperation for cell division.
Mitosis: a process in which a eukaryotic cell seperates the chromosomes in its cell nucleus into two identical sets of nuclei.
Cytokinesis: the process in which the cytoplasm of a single eukaryotic cell divides to form two daughter cells. Cytokinesis is usually initiated during the last stages of Mitosis and sometimes Meiosis.
6.What are the four phases of mitosis? What occurs at each phase?
Answer: prophase, metaphase, anaphase, telophase.
Prophase: the stage of mitosis in which the chromatin is condensed into a highly ordered structure called a chromosome were the chromatin becomes visible. It is when the DNA condensesw and the nuclear envelope dissolves, then the mitotic spindle starts to develop from the centrioles.
Metaphase: when the chromatids line up along the center of the cell, then the centromeres attach to fibers of the mitotic spindle.
Anaphase: occurs when the fibers of the mitotic spindle shorten causing the chromatids to pull apart. The chromatids pull apart so that the identical strands of DNA for each chromosome goes to one side of the cell while the other moves towards the opposite side. All of this results in each new cell having a full set of chromosomes.
Telophase: During telophase, the effects of prophase and prometaphase events are reversed and so two daughter nuclei form in the cell. The nuclear envelopes of the daughter cells are formed from the fragments of the nuclear envelope of the parent cell and then the nuclear envelope forms around each pair of chromatids, making the nucleoli reappear.
7.What are cell cycle checkpoints? Why are they important?
Answer: The cell cycle checkpoints are the G1, G2 and Metaphase checkpoint. Checkpoints are important because enzymes block the cell cycle from progressing until certain conditions are met.
8.What is apoptosis? What role does it play in the cell cycle?
Answer: Apoptosis is the process of programmed cell death
9.What is the difference between chromatin and chromosomes?
Answer: Chromatin has a Nuclear pore and Nucleosomes and Chromosomes have a Telomere and Centromere.
10.What is the role of the centromere? (What would happen without it?)
Answer: Centromeres are proteins that attach sister chromatids together. They are usually located in the center of the chromatids. The two sister chromatids together create a chromosome. The chromatids stay together with the centromeres until anaphase, when they separate into the two new daughter cells.
11.What is the difference between a chromatid and a chromosome?
Answer: When the chromosome is duplicated it's called sister chromatids, and so each one of them is called a chromatid. At times sister chromatids will be called as "chromosomes.
12.What events must happen in order for two sister chromatids to separate from one another and move to opposite sides of the cell? (What happens at the centromere? What happens to the centromere? What is the role of the mitotic spindle?)
Answer: During Anaphase sister chromatids are pulled apart and start moving to opposite sides of the cell. In the third stage of anaphase is when the sister chromatids of each replicated chromosome begin to separate. The fibers pull the centromere apart and the chromatids move away from one another towards the opposite end of the cell.
13.What would happen if two sister chromatids moved to the same side of the cell?
Answer: the fibers would not pull apart.
14.What happens to the mitotic spindle after mitosis?
Answer: The mitotic spindle breaks down after mitosis.
15.What are gametes? Where are they made in the body? How are they made?
Answer: A gamete is a reproductive cell having the haploid number of chromosomes, especially when a mature sperm or egg is capable of fusing with a gamete of the opposite sex to produce a fertilized egg. For gametes to form the gametes require cells to undergo a special type of cell division called meiosis, which is really two cell divisions happening one after the other.
16.What are the eight phases of meiosis? What occurs during each phase? How does meiosis differ from mitosis?
Answer: Prophase 1-->Metaphase1--> Anaphase1--> Telophase1/Cytokinesis-->Prophase 2-->Metaphase2--> Anaphase2--> Telophase2/Cytokinesis
17.How do crossing over and random assortment “mix up” genes so that children are genetically different from their parents?
18.Why are insertion and deletion mutations usually more harmful than substitution mutations?
19.How does nondisjunction affect the genes present in an organism? Specifically, why does it cause deformities?
20.What “super powers” must a cell acquire to become cancerous? How does it acquire these powers?
21.Compare and contrast oncogenes and tumor suppressor genes. What are they? How are they similar? How are they different?
22.Why is cancer primarily a disease of old age?
23.How do mutations cause genetic variation? Is this good or bad for the organism?
24.How do genetic diseases caused by point mutations differ from those caused by chromosomal mutations like nondisjunction?
25.What causes spontaneous mutations? What causes induced mutations?
26.How accurate is DNA replication? (That is, how often do point mutations occur?)
27.What type of mutation is shown here? AGTGCCGTCAC TCACGGCCAGTG
Assignment # 5: DNA Replication and Protein Synthesis.
Assignment # 5: DNA Replication and Proteing Synthesis
1. Why is DNA synthesis said to be "semiconservative"?
Answer: DNA synthesis is said to be "semiconservative" because each new double-stranded DNA contains one old strand and one newly-synthesized complementary strand.
2. What role do DNA polymerase, DNA primase (a type of RNA polymerase), helicase, topoisomerase, RNase H, and ligase play in DNA replication?
Answer: DNA polymerase plays a role in DNA replication because it is an enzyme that catalyzes the covalent bond between the phosphate of one nucleotide and the deoxyribose of the next nucleotide. DNA polymerase also forms the coplementary DNA strand in the 5' to 3' direction. DNA primase plays a role because it is the enzyme that catalyzes the formation of RNA starting segment. Helicase is the enzyme that breaks H-bonds. Topoisomerase unwinds DNA and DNA ligase catalyzes the connection of two Okazaki fragments.
3. What is the difference between how the leading strand and the lagging starand are copied during DNA replication? Why do they have to be synthesized differently in this fashion?
Answer: The difference between the leading strand and the lagging strand are that the leading strand's DNA primase creates a single RNA primer to start the replication while the lagging strand's DNA primase creates RNA primers in spaced intervals. Another difference is that the lagging starand matches the Okazaki fragments in the 5' to 3' direction while the leading strand just synthesizes the matching strand. In the leading strand the DNA ligase connects the fragment at the starts of the new strand to the end of the new strand. With the lagging strand the DNA ligase connects the Okazaki fragments to one another which covalently bonds the phosphate in one nucleotide to the deoxyribose of the ajacent nucleotide. They are synthesized differently because of the okazaki fragment.
4. What would happen if the insuficient RNase H were produced by a cell? What if insufficient ligase were produced by a cell?
5. What are the four key differences between DNA polymerase and RNA polymerase? (they are different molecules doesn't count as one!)
Answer: The four key differences:
6. Compare and contrast codons and anticodons?
Answer: For every three mRNA or codon specify an amino acid. example: GACCUAGCC. tRNA have an anticodon region that specifically binds to its codon.
7. What is alternative splicing? Why is it necessary to eukaryotes?
Answer: Alternative splicing is when Exons are "coding" regions. Introns are removed, the different combinations of exons form different mRNA which result in multiple proteins from the same gene.
8. During translation what amino acid sequence would the following mRNA segment be conversted into: AUG GAC AUU GAA OCG
Answer: Met, Asp, Lle, Glu, Pro
9. How come there are only 20 amino acids when there are 64 different codons?
10. How come prokaryotes can both transcribe and translate a gene at the same time, but eukaryotes cannot?
Answer: Prokaryotes can both transcribe and translate a gene at the same time because they occur simultaneously in the cytoplasm. Eukaryotes cannot because transcription occurs in the nucleus and translation occurs in the cytoplasm.
Saturday, March 13, 2010
Blog Assignment #4: Insulin Review Article Questions
1. In what journal did this article appear? When?
Answer: In the journal "SCIENCE" Volume 208 on April 4, 1980
2. What is the primary purpose of this paper?
Answer: The purpose of this paper is to explain how the recombinant bacterial plasmids that contain DNA which are complimentary to the human preproinsulin messanger RNA work and how they have been constructed.
3. What is the structural difference between insulin and proinsulin?
Answer: The structural differen ce between insulin and proinsulin is that insulin consists of two polypeptide chains, the A and B chains these chains are linked by disulfide bonds. The protein in insulin is synthesized as a single precursor polypeptide, and so in this process the A and B chains join via the C peptide. Proinsulin is different than insulin because it is contained within an even larger polypeptide called preproinsulin. Preproinsulin was first identified by in vitro translation of the messenger RNA derived from pancreatic B cells.
4. What is complimentary DNA (cDNA)?
Answer: Complimentary cDNA is derived from human insulinoma mRNA, this mRNA was isolated from 100mg of human insulinoma tissue and by the guanidinium thiocyanate procedure and also the double-stranded cDNA was prepared and cloned into the Pst site of pBR3222.
5. What is meant by the "polyA tail" or "polyoderylation" of a gene?
Answer: The polyAtail or polyadenylate is a tract of 40 nucleotides which are part of the nucleotide sequence of pH13.
6. What is meant by the statement that "insulin A and B chains are highly conserved"?
Answer: The statement that insulin A and B chains are highly conserved means that they are not variable such as the C peptide chain.
7. Which chain is most highly conserved?
Answer: Not one chain but parts or regions of both the A and B chain.
8. What do the researchers believe is the purpose of the C chain?
Answer: Researchers believe that the C peptide chain helps the proinsulin molecule to assume its correct three-dimensional conformation and that the greater amount of amino acid sequence variablility in the C peptide chain does not interfere with its ability to function in this manner.
9. Why does it make sense that the C chain is more variable(less highly conserved) than the A chain and B chain?
Answer: It makes sense that the C chain is more variable because first and second position codon changes are more prevelent than in the A and B chains.
10. What do the researchers believe is the purpose of the pre-peptide(D chain)?
-I was unsure of the answer so I am going to ask in class on Monday-
11. How does the human preproinsulin gene differ from rat preproinsulin (Rat I and Rat II)?
Answer: The human Preproinsulin gene differs from rat preproinsulin because the human sequence differs by only one nucleotide.
12. What is the first codon in the coding region of the gene(at the start of the pre-peptide) and what is the first amino acid in the polypeptide?
AUG
Answer: In the journal "SCIENCE" Volume 208 on April 4, 1980
2. What is the primary purpose of this paper?
Answer: The purpose of this paper is to explain how the recombinant bacterial plasmids that contain DNA which are complimentary to the human preproinsulin messanger RNA work and how they have been constructed.
3. What is the structural difference between insulin and proinsulin?
Answer: The structural differen ce between insulin and proinsulin is that insulin consists of two polypeptide chains, the A and B chains these chains are linked by disulfide bonds. The protein in insulin is synthesized as a single precursor polypeptide, and so in this process the A and B chains join via the C peptide. Proinsulin is different than insulin because it is contained within an even larger polypeptide called preproinsulin. Preproinsulin was first identified by in vitro translation of the messenger RNA derived from pancreatic B cells.
4. What is complimentary DNA (cDNA)?
Answer: Complimentary cDNA is derived from human insulinoma mRNA, this mRNA was isolated from 100mg of human insulinoma tissue and by the guanidinium thiocyanate procedure and also the double-stranded cDNA was prepared and cloned into the Pst site of pBR3222.
5. What is meant by the "polyA tail" or "polyoderylation" of a gene?
Answer: The polyAtail or polyadenylate is a tract of 40 nucleotides which are part of the nucleotide sequence of pH13.
6. What is meant by the statement that "insulin A and B chains are highly conserved"?
Answer: The statement that insulin A and B chains are highly conserved means that they are not variable such as the C peptide chain.
7. Which chain is most highly conserved?
Answer: Not one chain but parts or regions of both the A and B chain.
8. What do the researchers believe is the purpose of the C chain?
Answer: Researchers believe that the C peptide chain helps the proinsulin molecule to assume its correct three-dimensional conformation and that the greater amount of amino acid sequence variablility in the C peptide chain does not interfere with its ability to function in this manner.
9. Why does it make sense that the C chain is more variable(less highly conserved) than the A chain and B chain?
Answer: It makes sense that the C chain is more variable because first and second position codon changes are more prevelent than in the A and B chains.
10. What do the researchers believe is the purpose of the pre-peptide(D chain)?
-I was unsure of the answer so I am going to ask in class on Monday-
11. How does the human preproinsulin gene differ from rat preproinsulin (Rat I and Rat II)?
Answer: The human Preproinsulin gene differs from rat preproinsulin because the human sequence differs by only one nucleotide.
12. What is the first codon in the coding region of the gene(at the start of the pre-peptide) and what is the first amino acid in the polypeptide?
AUG
Thursday, February 4, 2010
Assignment Two: Diseases Associated with Obesity
Diseases Associated with Obesity
Type Two Diabetes
The disease of Type Two Diabetes is the most common form of Diabetes and can occur at any age but mostly in people who are overweight or over middle age. Type Two Diabetes occurs when the pancreas does not produce enough insulin and so the body is resistant to the insulin that is produced. Insulin is the hormone that helps your body use blood sugar and acts as a key which opens up cells to accept all the glucose that is required for a person to function. A person with Type Two Diabetes does not have the same sensitivity as a person without the disease and in turn the insulin receptors do not work in the same manner. High blood glucose levels can lead to many different diseases such as heart attack, stroke, blindness, kidney failure, and nerve damage. Daily physical activity and a healthy diet will decrease the chances of the complications that come with diabetes as well as the daily intake of medication prescribed by a doctor.
Hypertension
When a person has hypertension their blood pressure is consistently high even when a person is at rest. Blood pressure is essential for blood to move through our bodies bringing needed oxygen to our organs and muscles and carrying away carbon dioxide and waste. Blood travels a quite a long distance starting at the heart and that distance is 60,000 miles long, so 80 times a minute blood is pumped into and out of the heart muscle flowing into arteries branching out from the heart and then into smaller arteries called arterials. Blood makes its trip throughout the body and then into veins and soon after returns to the heart. A person pumps about 2,000 gallons a day throughout the body. If your heart pumps extra hard to move the blood through the body, this can take a horrible toll on the arteries. Normally arteries are rubbery but if the arteries stretch they develop groves on the inner walls of microscopic scar tissue which in turn develop diseases that could further damage the body.
The disease of Type Two Diabetes is the most common form of Diabetes and can occur at any age but mostly in people who are overweight or over middle age. Type Two Diabetes occurs when the pancreas does not produce enough insulin and so the body is resistant to the insulin that is produced. Insulin is the hormone that helps your body use blood sugar and acts as a key which opens up cells to accept all the glucose that is required for a person to function. A person with Type Two Diabetes does not have the same sensitivity as a person without the disease and in turn the insulin receptors do not work in the same manner. High blood glucose levels can lead to many different diseases such as heart attack, stroke, blindness, kidney failure, and nerve damage. Daily physical activity and a healthy diet will decrease the chances of the complications that come with diabetes as well as the daily intake of medication prescribed by a doctor.
Hypertension
When a person has hypertension their blood pressure is consistently high even when a person is at rest. Blood pressure is essential for blood to move through our bodies bringing needed oxygen to our organs and muscles and carrying away carbon dioxide and waste. Blood travels a quite a long distance starting at the heart and that distance is 60,000 miles long, so 80 times a minute blood is pumped into and out of the heart muscle flowing into arteries branching out from the heart and then into smaller arteries called arterials. Blood makes its trip throughout the body and then into veins and soon after returns to the heart. A person pumps about 2,000 gallons a day throughout the body. If your heart pumps extra hard to move the blood through the body, this can take a horrible toll on the arteries. Normally arteries are rubbery but if the arteries stretch they develop groves on the inner walls of microscopic scar tissue which in turn develop diseases that could further damage the body.
Atherosclerosis
Atherosclerosis is the conditions were the build up of waxy plaque builds on the inside of blood vessels, and hardens the arteries. What usually occurs is that the inner layer of the artery wall thickens, secondly the artery's diameter is reduced in size causing the blood flow and oxygen delivery to decrease. This in turn can cause the sudden formation of a blood clot. Atherosclerosis can cause a heart attack if it is completely blocked and the blood cannot flow freely. The plaque that forms is made of fatty substances, cholesterol, and the waste products from cells, calcium as well as fibrin. The causes of this condition are usually aging, high blood pressure or diabetes.
Atherosclerosis is the conditions were the build up of waxy plaque builds on the inside of blood vessels, and hardens the arteries. What usually occurs is that the inner layer of the artery wall thickens, secondly the artery's diameter is reduced in size causing the blood flow and oxygen delivery to decrease. This in turn can cause the sudden formation of a blood clot. Atherosclerosis can cause a heart attack if it is completely blocked and the blood cannot flow freely. The plaque that forms is made of fatty substances, cholesterol, and the waste products from cells, calcium as well as fibrin. The causes of this condition are usually aging, high blood pressure or diabetes.
Stroke
The condition of a stroke is when there is a sudden death of brain cells due to the inadequate flow of blood. Without blood flow the supply of oxygen and nutrients to the cells of the brain quickly begin to die. The cause of a stroke may cause paralysis, a coma, or sudden death. Having a stroke is extremely serious and is the third leading cause of death in the United States. Men have a much greater chance than women do at experiencing a stroke and about two thirds of people over the age of 65 experience strokes. Taking care of your body with good nutrition and proper exercise can decrease the chances of a stroke by keeping the heart healthy.
Heart Attack
A Heart Attack is the death of the heart muscle which is due to the loss of blood supply due to the blockage of an artery. In this case the blocked artery would be the coronary artery which supplies blood to the heart. One of the major symptoms of a heart attack is the instability of the muscle tissue of the heart which in turn causes extreme chest pain. Heart attack deaths are often caused by the patient being unable to reach the hospital on time and only approximately 90-95% of victims of a heart attack survive even after reaching the hospital. One way to treat a heart attack is to administer drugs soon after that dissolve the blood clots and open up an obstructed artery. Patients who have experienced a heart attack are usually hospitalized for several days and are under the close supervision of a physician.
Assignment Two: Enzymes Animation Questions
Enzyme Animation Questions
1. Enzymes are
a)lipids
b)proteins
c)carbohydrates
d)nucleic acids
e) steroids
answer: b)proteins
2. Which of the following binds to the active site of an enzyme?
a)water
b)product
c)substrate
d)any other enzyme
e)none of the above
answer: c)substrate
3. Which of the following correctly represents the mechanism of enzyme function?
a)S+P -> E-P ->E + P
b)E+P -> E-P->E-S-> E + S
c)E+P -> E-S -> E-P ->E + P
d)E+S -> E-S ->E-P -> E + P
e)E+S -> E-P ->E-S -> E+ S
answer: D
4. An enzyme can only bind one reactant at a time.
a)True
b)False
answer: b)False
5. An enzyme speeds up a chemical rection in the cell, but can only be used once.
a)True
b)False
answer: b)False
Assignment Two: Nutrition & Cells Practice Questions
Nutrition & Cells Practice Questions
1. There are many differences between vitamins and minerals. First off vitamins are defined as small organic molecules and most vitamins are co-enzymes. Vitamins are water-soluble as well as fat-soluble. The water soluble vitamins include all B and C vitamins and tend to seep out of boiled vegetables as well as excreted through urine. The fat soluble vitamins are stored in fat and are not as easily released from the body and can be extremely toxic in high concentrations. All the fat soluble vitamins include vitamin A,D.E and K. Minerals are not organic like vitamins but are actually small in-organic molecules that also happen to be simple ions. Minerals are water-soluble and unlike vitamins do not happen to be fat-soluble.
2. Free radicals are highly reactive molecules that are left over from natural metabolic processes or simply come from the eviornment. Free radicals can cause damage to a human beings DNA that can eventually lead to cancer. The body can protect itself from free radicals by the consumption of antioxidants which can intercept and neutralize the radicals.
3. Essential Amino Acids are acids that can be consumed from food intake and most animal meat or animal protein which contains all of the essential amino acids needed for nutrition. Essential fatty acids are acids that cannot be synthesized by cells and belong to two families: Omega-3 and Omega-6. Essential fatty acids are involved mostly just in biological processes and not in energy storage.
4. Hydrogenation is when unsaturated fats plus hydrogen gas with addes pressure equals out to saturated fats. Hydrogenation affects the chemical structure of fats by causing trans-fats to form an unnatural conformation which is synthesized via hydrogenation itself, this in turn creates a clogging of the arteries and raises bad cholesterol.
5. Bacteria when used with a cap;ital 'B' refers to a domain name, thus Bacteria with a lower case 'b' refers to a term used with "Prokaryotes".
6. The organelles that are found in all cells are as follows:
The Plasama membrane, Nucleus(Chromatin-DNA, Nucleolus, Nuclear Envelope), Ribosomes, Rough ER, Smooth ER, Golgi Apparatus, Centrioles, Mitochondria, Cytoskeleton, Vesicles, Peroxisomes, Lysomes and small Vacuoles.
7. A concentration gradient is the action of diffusion that includes passive and active transport.The role that it plays in Osmosis is that it diffuses water through the action of active transport which is the movement of molecules from low concentration to high concentrations. Active transport also requires energy or ATP. Facillitates diffusion is also know as "Passive transport" and brings a net movement of molecules from high concentration to lower concentration until they reach equilibrium.
8. Cellular respiration occurs in Prokaryotes across the plasma membrane and in the mitochondria of eukaryotic cells.
9. The components found in both Prokaryotic cells and Eukaryotic cells that have different structural characteristics are the following:
Plasma Membrane: which in Eukaryotic cells have internal organells composed of lipid bilayer membranes.
Cytoplasm: which consists mostly of water and is fluid that fills the cells and surrounds the organelles.
DNA: DNA in prokaryotic cells happens to be linear or cirular in shape and is contained in the nuclear region. DNA in Eukaryotic cells is much longer and coils around the histone proteins. The DNA is always linear in shape and is contained in the nucleus, DNA in the eukaryotic cell is also known as chromatin when it is "relaxed" and as chromosomes when it is supercoiled.
Ribosomes: float freely in the cytoplasm of both Prokaryotic and Eukaryotic cells.
10. Proteins, Ribosomes and lipids are all manufactured in the Cytoplasm.
11. The three types of Endocytosis are as follows:
1. Phagocytosis: which has a plasma membrane, a phagosome(which is also
knows as a food vacuole) as well as a solid particle.
2. Pinocytosis: which has extracellular fluid, a vesicle and cytoplasm.
3. Receptor Mediated Endocytosis: which has a receptor, a coated pit, a
protein and coated vesicle.
12. Three cellular components that contain microtubules are:
13. The endosymbiotic theory is the theory in which mitochondria and chloroplasts are the results of years of evoution that is initiated by the endocytosis of bacteria which instead of becoming digested became symbiotic.
14. Mitochondria and Chloroplasts have in common that they both contain their own DNA and ribosomes. The ways in which they differ are that Mitochondria breaks down glucose using oxygen to produce energy for a cell, this process is also called: cellular respiration. Chloroplasts use light energy to convert atoms into water as well as CO2 into sugars and starches. Chloroplasts also have a double membrane and conatin Grana, Stroma and Chlorophyll.
15. The difference between lysomes and peroxisomes are that lysomes contain digestive enzymes and fuse with vacuoles that conatain food. Lysomes also cell refuse and capture bacteria. Peroxisomes are found in animal cells, and plant cells. In animal cells they are full of enzymes that oxidize amino acids. In plant cells they are full of enzymes that oxidize fat. In both the animal and plant cells they convert hydrogen peroxide into water.
16. Bacterial DNA differs from Eukaryotic DNA by
17. The two prokaryotic cell components that help bacteria cling to surfaces are the slime layer and the fimbria.
Friday, January 29, 2010
Assignment One: Biochemistry Questions
BIOCHEMESTRY QUESTIONS
1. The difference between an Endergonic reaction and an Extergonic reaction is that an Endergonic reaction is positive and it is were energy is absorbed. An Exergonic reaction is were the change is negative.
2. Na+ is 2 protons, 8 electrons, 3 valence electrons
3. A Covalent bond is when the nuclei of two atoms are strongly attracted to electrons and share those electrons. An Ionic bond is an attraction between two ions that ends up forming a salt. A Hydrogen bond is when hydrogen atoms in a polar compound are attracted to ions or other polar compounds. The strongest would be Hydrogen because the strands of DNA are held together by hydrogen bonds. The weakest would be Ionic bonds which just form salt.
4. The 4 types of organic macromolecules are:
Polysaccaharides, Lipids, Nucleic Acids, Polypeptides
Polysaccaharides are starches and sugars collectively called carbohydrates. Lipids are fatty acids, Nucleic Acids are nucleotides and last Polypeptides are amino acids.
5. Glycosidic bonds link together sugar molecules.
6. Eight types of nucleotides are that each nucleotide is composed of a nitrogenous base, a sugar and a phosphate.
7. The reason that phospholipds for micelles in water are because phosopholipids ar fatty acids that create barriers in water.
8. Saturated Fats have no double bonds between the carbon atoms of the fatty acid chain and are fully saturated with hydrogen atoms.
Unsaturated Fats have one ore more double bonds in the fatty acid chain.
9.
10. The three differences between DNA and RNA are the following: Sugar is in the backbone of both DNA and RNA but DNA has Deoxyribose and RNA has Ribose. Another difference is that RNA contains Uracil and not Thymine, last RNA is single stranded while DNA is double stranded.
11. The five nitrogenous bases that form eight nucleotides are Adenine, Guanine, Cytosine, Uracil, Thymine.
12. 0
\
P --- 0
/
0 --- 0
13. The characteristics of reactive groups are what cause regions of the proteins to attract and repel one another this in turn is what causes the protein to fold into its final shape.
14. Primary Structure: a linear acid sequence
Secondary Structure: folding into helics and beta sheets
Teritiary Structure: folding into final 3D shape but does not always apply to all
proteins.
Quaternary Structure: folding into final 3D shape but does NOT always apply to all
proteins.
15. The cause of the structural shape of receptors to change is because the receptors communicate the information by causing the conformational change that transmits a signal cascade.
16. There would be no chemical reactions that would bring molecules together.
17. The result would be that it would catalyze the reaction over and over.
18. Enzymes are highly specific for their substrate because they substrate binds to the enzyme forming an enzyme-substrate complex.Receptors are highly specific for their ligands because they cause the receptor to undergo conformational change.
19. Proteases break down proteins and are enzymes that conduct proteolysis, proteases also work best in acidic conditions.
Thursday, January 28, 2010
Assignment One: About Me
My name is Imelda Barron and I am 29 years old and was born and raised in Oxnard, California. I have lived here for most of my life but moved to Hollywood, California for 4 years and worked at a Vintage clothing retail store on the Melrose shopping district were we bought and sold clothing to movie studios & overseas vintage buyers. I moved back to Ventura County because I missed my family and I made the decision to go back to college and obtain my degree in Pyschology. Before coming back to college I attended Lu Ross Academy in Ventura, California to study Makeup Artistry, soon after I started my first semester back at school at Ventura Community College. I am an artist and enjoy drawing, painting, makeup artistry, fashion as well as writing & music. I have worked in the retail clothing industry for years and was also a barista at an independent coffee house in downtown Ventura. I am currently employed by Wells Fargo Bank in Camarillo, California and enjoy my job very much but my dream is to work in the field of Psychology as well as continue pursuing my art. I am taking this course because it is a pre -requisite for my major.
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