1. How many carbon atoms are there in the molecule shown below? What is the shape of the molecule at the carbons nearest to the oxygen?
a. 20 carbon atoms
b. Shape= trans-planar
2. In the example shown, what would happen to the signal if the channel was stuck in the “open” position? What if the channel were unable to open?
a. If the channel were stuck in the “open” position, the signal would be continually sent to the brain. For example, if a message about olfaction was getting continually sent through the membrane channel to the brain, one would continually smell a certain aroma. However, if the channel were unable to open, ions would not be able to pass through, thus not changing the composition of the cell, resulting in no message being sent to the brain. So, the brain would never perceive the aroma.
3. In this analogy, what is the boat? What is the leak? What is the bucket?
a. Boat: cell membrane
b. Leak: continually open ion channel
c. Bucket: pump- which pumps cations out of the cell
In class work on Friday January 7, 2011
Part I: Sight Activities
Optical Illusions:
Checkershadow Illusion:
This was the first illusion that we viewed in class. At first, I did not believe that the squares were the same color. I was very convinced that these were two different shades of grey. However, after cutting out the squares and comparing them side by side, I was amazed to see that they were indeed the same shade! I was surprised at how my own eyes had supposedly played a trick on me.
Simultaneous Contrast Illusion:
When I first looked at this illusion it kind of made my head hurt! I found it difficult to keep up with the video and all that was happening. I was perplexed to see that simply by changing the background shades the boxes can look like two totally different colors. That’s quite the trick!
Vasarely Illusion:
I thought this one was kind of cool! When the diamond shapes were not stacked there was no illusion, it was just shapes laying side by side. However, just by changing the way the shapes were configured, it created a completely different “star” shape. It’s crazy how some different maneuvering and placement of shapes can change the entire illusion.
Craik-Obrien-Cornsweet Effect
This one kind of made my head hurt slightly! Although all the shapes were squares, by turning each shape on its side made them look like each piece was identical in shade. This seemed quite odd to me since in a square all sides are supposed to be equal. It seems that even though these shapes had varying shades, they actually looked identical based on where you configure them.
Koffka Ring
Of this grouping of illusions, this one was the craziest to me. When the ring was normally situated at the start of the view it was a uniform grey color. However when it was split it looked like two totally different shades! Also, when it was shifted it looked like a swirl with multiple different shades comprising it. This shows again, that the change in background of an object can really change one’s entire perception of color/shade.
Curve Ball Illusion
This was another of my favorite illusions. It was amazing how when I looked straight at the ball it appeared to be falling straight down. However, when looking at the ball out of my periphery, it looked as if it was going sideways! This was a completely different perspective than before! It was also interesting to play around with the contrast part of the illusion.
Leaning Tower Illusion
This illusion took a while for my partner and me to figure out. I was shocked to hear that this was the same picture laid side by side. When we read further about the illusion it said that our brain perceives something completely different because of where the images are placed. I am learning that a lot of what I see is based on multiple factors. Simply where an object is placed can greatly change the reality that I see.
Is He Coming or Going?
This was an extremely frustrating illusion for me. When I first looked at the image, I was convinced that the horse and rider were faced away from me. However, after looking away and coming back to the image I was surprised to see that it now looked as if the image was coming toward me! My partner even had difficulty seeing both views right away and we had to point them out to her. It was frustrating because no matter how many times you looked at it, it appeared different every time! Which way was right?! We may never know!
Spinning Cat Illusion
This was my favorite of all of the illusions. We first started by just looking at the spinning cat. It appeared to be spinning in a uniform motion and direction. However, half way through the cat switched. At first we did not buy into the belief that it was our minds making the cat switch. So, my partner and I decided to test it out. We told each other when we each perceived the cat to be switching directions. Much to our shock, we found out that the cat switched at different times for each of us. It wasn’t a trick played on us by the website! Our brains were in fact switching the direction the cat turned! It was a weird feeling, I felt as if I had special powers to control the spinning! It reminded me that my mind really is a more powerful thing than I previously thought.
Monkey Business
This was the final illusion that I looked at. I was very proud of myself at first that I had correctly counted the correct number of passes between the players in the white shirts. However, I realized that I had completely missed the giant gorilla, change on curtain colors, and player leaving the game. It was crazy to think that when we are focused on one thing so intently, we can become completely unaware of other major things going on literally right in front of our noses.
Color Blindness:
This was also a very interesting part of the lesson for me. It was an interesting experience to observe how people with different kinds of color blindness view the world. It really surprised me how much of the world they seem to miss out on! When I first viewed some of the images from the perspective of a color blind person, it did not seem to be that bad. However, as I scrolled through more images I was amazed at how bland their outlook was. A good amount of the images were from the view of a person with Dichromate color blindness. These images were lacking vital parts and looked completely drab. It got me thinking about how things would seem so much less exciting and intriguing if I had to see the world from that point of view. Viewing these images made me very thankful for my sight and the chance to experience God’s creation to the fullest extent possible!
Part II: Lab Activity
Colorful Molecules Found in Food
For this part of the activity, my group was responsible for making a red cabbage solution. After going through the appropriate steps we got a series of 9 test tubes. These tubes each contained a deep bluish-purple colored liquid. We put various buffers into these solutions and watched the colors change. The first tube was bright, hot pink. The tube with solution 3 was a lighter, softer pink. The tube with buffer 5 was light lavender. Tube 6 was a slightly darker lavender. The tube with buffer 7 was a periwinkle blue color. The tube with buffer 8 was a medium blue color, while tube 9 was greenish-blue. Tube 10 was turquoise-green while 11 was a bright green. We soon found out that the tubes created a spectrum of colors. The colors went from pink, to purple, to blue, to green. They made a fabulous rainbow when placed side by side!
Our solution was much “prettier” looking than our classmates with the spinach solution. Their tubes ranged from a dark brown, to a green color. All of their tubes looked about the same and were murky in appearance, as opposed to our clear solutions. For our tubes, when we added bleach the solution turned clear. It appeared as if the bleach had stripped all the color out of the solutions. When hydrogen peroxide was added, the solution began to get lighter and lighter as time passed. However, it took longer to strip away the color than it did with the bleach. When bleach was added to the spinach solution, the color became a light yellow color. When hydrogen peroxide was added, the liquid became a little lighter, but mostly just bubbled.
Fluorescence
These are the results of how each appeared under the black light:
- GFP and any other available fluorescent proteins: This appeared neon green
- Quinine tonic water: This appeared fluorescent blue.
- White towel: This looked bright blue under the light.
- Chlorophyll: This appeared bright red when in a bright light. It apparently looks blood red in UV light. However, under the black light it appeared just a bright green color.
- mTangine: This looked neon, bright pink. This was my favorite color of them all!
Why do white clothes look like they do under a black light?
The reason that white clothes glow under black light is because of the detergents used in white clothing to make them appear extremely white. The shirt thus contains “phosphors” that take the UV light and convert it to white light. Thus, the t-shirt glows. The reason that we want our whites to absorb a color of light we can barely see and emit a brighter one is so that our clothes do not show excess stains or imperfections. That is why we use detergents, so that our whites appear flawless and vibrant.
Website used: http://science.howstuffworks.com/innovation/black-light.htm
What color do you think rods see best?
My guess: I think that rods see neon green the best.
Wikipedia answer: “Rods are most sensitive to wavelengths of light around 498 nm (green-blue).”
Structures of chlorophyll and red cabbage:
What do these colorful molecules have in common?
One similarity between these two molecules is that they both give off intense color when put up to UV light. Also, they are both molecules found in plant substances and thus give the plant its color. Also, these molecules are very complex and consist of a significant amount of double bonds.
Can you make any general statements about the chemical properties that lead to color?
Some general chemical properties that lead to color are having many double bonds. Also, having a more complex structure consisting of double bonds and tetrahedral shapes seems to be a general property.
What can you say about their bonds and molecular shape?
Some similarities are that these molecules both have many double bonds. Also, they contain many ring structures. Many of the bonds are made with hydrogen in each of the molecular shapes.
Bleach and Hydrogen peroxide:
What do you think they remove color from these molecules? How might this help for stain removal?
Since bleach and hydrogen peroxide are eliminating double bonds, this means that they are destroying the structure of these molecules. If these structures are being destroyed, then they will not be able to show their color any longer. So, these chemicals are helpful for stain removal, because breaking up those double bonds destroys the structure and thus the color of those stains on clothes.
How might the molecules in fruits and vegetable function as antioxidants?
These fruits and vegetables may function by destroying those harmful oxidants in the body. These antioxidants may attack those oxidants before they even interact with the body’s proteins and DNA. If those oxidants are not destroying DNA and proteins, are body will be better able to fight off disease, create new cells, maintain organ integrity etc. Our proteins and DNA are the building blocks of all our internal cells and structures. If fruits and vegetables can help to eliminate something that destroys DNA and protein, our bodies will be much more resilient and healthier overall.
Pre-Class Homework for January 10, 2011
Are all salts the same?
After reading through these various salt labels, I found that there are many different kinds of salt. It appears to me that all salt is NOT the same. There are innumerable varieties of salt from all over the world. They all serve very different purposes and are even specific to different dietary restrictions. This powerpoint really attested to the fact that salt is really more than simply a seasoning.
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