Warm Up 4 is due Wednesday, February 12, 2003 at 9:30 am.

WarmUp1, WarmUp1 Responses, WarmUp2, WarmUp2 Responses, WarmUp3, WarmUp3 Responses, WarmUp4,

QUESTION 1: One of my favorite Biology quotes is listed at the beginning of the lecture notes for photosynthesis: "Life is woven out of air by light". Aside from being a pretty phrase, what does this quote mean in terms of photosynthesis - think about this quote and in your own words, how would you say is life woven out of air by light??

From SL: Q1 = The sun's energy is converted to a chemical energy and it then makes sugar which is converted to cellulose, starch and sucrose. It's like a dance between the sun and water and the gases in the air.
From Mom: Q1 = Plants are able to convert sunlight (light) and oxygen (air) to energy in the form of sugar, via photosynthesis. Thus, energy and carbon have entered into the "web of Life", according to our text. According to our clas notes, Plants, protists and cyanobacteria can make sugar out of water and carbon dioxide, which is then converted to energy for those and other earthly organisms (except those in the Archae domain).
From Enola: Q1 = The quote refers to the process of changing sunlight into energy that allows an organism to live. I would put it in my own words and say, "La vita è tessuta da aria da luce." That's Italian for "Life is woven out of air by light."
From Piggy: Q1 = Oxygen is released and carbs are synthesized by carbon dioxide. Light is used as an energy source.
From Dubbin: Q1 = Well, Plants cant live without sunlight, and the human race cant live without sugar for their coffee.

QUESTION 2: Where within the plant cell does photosynthesis occur? Describe the location of the two main 'acts' of photosynthesis: the Light reactions and the Calvin Cycle reactions. What is the end result of the light reactions? What is the end result of the Calvin Cycle reactions? (you will need your notes to answer these questions!)

From sunshine: Q2 = These reactions take place in the chloroplast. All the energy made in the Light Reactions is used to make sugar and re-form RuBP. The end result of the Calvin Cycle is the cell has made sugar from sunlight.
From kinder: Q2 = Photosynthesis occurs within the chloroplast of a plant cell. In Act I: the light reactions location occurs in the thylakoid membrane stacks. In Act II: the Calvin Cycle the location of reactions that occur are in the chloroplast stroma. The end result of the light reactions is chemical energy (ATP and NADPH). The end result of the Calvin Cycle reactions is the cell has made sugar from sunlight.
From Is it over yet?: Q2 = I am totally lost on this question. I think that chloroplast and chlorophyll have something to do with it.
From Sun-Lover: Q2 = The light reaction occurs in the thylakoid membrane staks, and the Calvin Cycle reactions occur in the chloroplast stroma. At the end of the light reaction, chemical energy is made to move onto the Calvin Cycle reactions. At the end of the Calvin Cycle reactions, all of the energy made in the previous reaction is used to make sugar and re-form RuBP.

QUESTION 3: The sun is a clean, free, limitless (at least for the next 5 billion years or so...) source of energy that photosynthetic organisms have utilized for the last 2 billion years to supply their energy needs. Why do you think humans haven't switched to using the energy of the sun for our external energy needs like transportation, electricity, climate control of our homes?

From Hee-Haw: Q3 = Because we haven't really evaluated the advantages/disadvantages. Most likely when we run out of current sources is when we will decide to switch over. Humans have the tendency to wait till the last minute when there is a problem.
From dawg: Q3 = I think part of the reason is inconsentency of the weather. one day it is bright and you will have plenty of energy but then you might go a week without a clear day. Right now solar energy can't handle a lot of the demands our energy needs require. The power reserve runs out too quick.
From Captain: Q3 = There are tons of solar powered sources around the world, we just havent got our lazy polluting butts in gear.
From Socrates: Q3 = The main reason humans have used the sun as our main source of energy is because before we had the technology for solar power, people realized you could get quite rich from destroying the earth's resources for our energy. Humans will use the sun as the main source of energy when we use up all of our natural resources.
From kid: Q3 = I think in 50 years from now you will see more and more movement toward using the sun as means for transportation, electricity, etc. It's always been human nature to use the most accessible resources and to this point it's been gas/oil. But, as we are finding out those might not always be in our future. You see more energy cars that use electricity and solar powered houses and cars.
From Billy Bob: Q3 = I do not think that we have switched to the sun for means of energy supply, because it was not our first way of providing energy and uour society had grown to be used to the other sources of energy and many companies and business and in whole our economy would suffer if all of a sudden there was no need for all of the other uses of energy.
From grateful student: Q3 = Unfortunately, the internal combustion engine was developed long before people learned to harness the sun's energy. I feel the reason why humanity hasn't made the change to solar power is based upon money, power and politics. Certain people have become very powerful due to oil. These people have enough money now that they can buy the government. Now, these people are in the government. Why would these people pass laws that will eventually lead to a huge loss of money for them? It isn't going to happen. Since a lot of oil comes from the middle east, the terrible events that are taking place just might lead to a change in the way we fuel our country.

QUESTION 4: Well, did you survive the first N100 exam? Questions, comments or suggestions --- good or bad --- on Exam 1?

Q4 = Exam I---Survive, I wouldn't exactly call it survival. If it was a reality show I would have been the first one voted off.
Q4 = I think I survived it but those "all the above" questions are stressful!!!!!!!!!!!
Q4 = I really hate those a/b, a/c, all of the above options! But I know they're there to make sure I really know the material.
Q4 = i wasn't prepared at all. due to my lack of focus, i went in to the test just hoping to score a few points. now i have thqat focus back and i have my work cut out for me.
Q4 = I think I did okay on the exam, I wish I would have prepared a bit better for it. Next time I am going to take advantage of all materials that could help me on the test and I am going to get a bigger head start on studying.
Q4 = Well I showed up and took the test, but I don't think I did as well as I wished. Better luck next time.
Q4 = AHHHHH!!!! i think i bombed the test. i am really concerned about my grade. Is this exam going to kill my grade????
Q4 = I survived, but didn't feel so great about it. I'm gonna work a little harder before this next one!
Q4 = The main problem that I faced was the uncertainty of what was going to asked on the test, and how it was going to be asked. I will do better next time.
Q4 = I didn't study that much...so it was really hard! I'll definitly study more for the next one.
Q4 =For me I need to use flashcards and prepare NOW for exam two. Instead of waiting a week before.
Q4 = The test followed the objectives, just like you said. I felt very prepared after studying the objectives you layed out for us.
Q4 = I had a pretty hard time with the first test but it is common for me to have trouble on the first test in all my classes because you never really know what to expect so its hard to study but now that i know what to expect i shouldnt have such a hard time on the upcoming tests.
Q4 = I hope so...I feel pretty good about it--Can't wait to see the results!!
Q4 = i liked it.

The text of this "What is Biology Good For" exercise is copyrighted under the name of Dr. Kathleen A. Marrs, 1999, 2000, 2001, 2003. There are no restrictions on its use by educators or by non-profit institutions as long as its content not modified, proper copyright acknowledgement is retained, and this statement is not removed.

****************************************************************