Many people today need surgery, for reasons that range from wisdom teeth to serious diseases. Dissection is a big part of surgery. For surgeons to accurately pierce skin without damaging anything more vital, they must be able to have an extreme amount of control. That amount of control takes a lot of practice. Dissecting vertebrates like frogs and other creatures that are basically similar to humans allows that practice, but without it, surgery would be much more dangerous. So, what if dissecting animals was illegal?

With computer technology as it is today, virtual dissection may be the first answer into someone's head. Unfortunately, even though the pictures would provide familiarity, virtual dissections would not properly simulate the necessary amount of force, or even provide practice for the actions. Another answer could be dissecting dead humans who donate their bodies to science. The fact is though, not very many people donate their body, and so there would not be enough to provide every hospital or medical union with adequate practice. The fact remains that animal dissection is an extremely important factor in preparing for sometimes

Let There Be Light

5/29/2013 21:59:02

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Light follows a complex, but not very long path from the cornea to the brain. First, of course, light hits the cornea, or the transparent section of the eye joined with the sclera. The sclera is the hard white section of the eye. Just beneath the cornea are two more sections: the iris and the pupil. The pupil is the hole through which light travels into the eye. The iris is the colored ring around it. The iris and other ligaments, or muscles, expand or contract the iris, varying the amount of light that enters. The light has now passed through all of the visible sectors of the eye and is now inside.

After the pupil is the lens. The lens is what focuses the light. Lenses are found everywhere and there are two main types: convex and concave. Convex lenses refract the beams closer to each other so each one eventually crosses in a focal point. Concave lenses refract the beams away from each other and never create a focal point. The lens in our eye is a convex lens. After the beams pass through the lens, they hit the retina, a section of light-sensitive cells. The image is then reflected along the optic nerve to the brain. Unfortunately, the image is upside down, because of the crossing, so the brain has to flip the image to make everything look right.

Fresno Chaffee zOO

5/29/2013 21:55:50

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Seeing at my Chaffee Zoo was a very interesting experience. After the snack after the bird show, we all went to find our animals. There were three different animals in out group, and two were at the reptile house, so we went there first. My animal is a blue duiker; kind of like a small antelope, so it obviously was not at the reptile house. Unfortunately, after we went to the reptile house, the blue duiker enclosure was on the opposite end of the zoo. We walked across the zoo, using stations as our reference points. 

When we got to the corner, saw a duck exhibit. Looking at the map, we realized we needed to walk across a small footbridge. At the blue duiker enclosure, all we apparently saw were the tortoises it was supposed to share the exhibit with. Then one of our group members saw it behind a bush. That makes sense, because blue duikers' main defense against predators is their ability to quickly disappear into the bushes when frightened. Seeing the duiker was a shock. All of the images we worked with gave an impression 3 or 4 times too large! The blue duiker is supposed to be the world's smallest antelope, and now my group and I understand why.
 
To understand how rainbows form, it is first necessary to understand the concept of color. Visible light is a small part of a huge scale of electromagnetic waves. Waves of visible light that have different wavelengths are different colors. The longer the wavelength, the closer to red. The shorter the wavelength, the closer to violet. White light is made up of all of the different wavelengths. Black is formed when none of them are present. White light can be refracted into the 7 main wavelengths that made it up: red, orange, yellow, green, blue, indigo, and violet.

There are a few things that can separate light in that way. One is a prism, a specially shaped object of glass. The other is water droplets. When it rains, and the sun emits white light, the droplets refract the light into the main colors of visible light. This creates a rainbow. The most commonly used definition for the criteria for a rainbow is for the sun to shine while it rains, but any combination of water and light has the potential to create one.
 
The sky is blue because of the process of scattering. Scattering is where a material or group of materials diffuses the light and transmits it differently. The higher a wave's frequency, the more it is scattered. Frequency is the amount of time it takes for a wave to pass the same point twice. The shorter the wavelength, or distance between two identical points on a wave, the higher the frequency. Light is radiated from the sun and across space to Earth. When on Earth, it reaches the atmosphere. The atmosphere is very different from the vacuum that is space, and the gasses have a curious effect on the light rays. 

Blue is one of the waves of visible light with the highest frequency. Visible light is a small sector on the electromagnetic spectrum, but the different wavelengths inside of it create all different types of colors. The seven main ones are red, orange, yellow, green, blue, indigo, and violet; in order of increasing frequency. Since blue has a high frequency, it is scattered throughout the sky and creates the layer of light blue.
 
I don't know why the sky is blue, but I have a few ideas. I know that the oceans are relatively bluish, even though water is naturally clear, because they reflect some of the blue from the sky. I know that the gas giants Neptune and Uranus look blue and/or green because of the concentration of methane in our atmosphere. Our atmosphere is 78% nitrogen, 21% oxygen, and 1% other gasses. It could be possible that the mixture of gasses in the atmosphere creates a light-bluish layer of gas when combined with the lighter, higher-up pressures. Even so, that is probably incorrect, because the clouds on Uranus and Neptune are... clouds. The color of our sky is something different.

The sky could be blue because the oceans are blue. Earlier I said that the oceans reflect the skies, but it could be the other way around. The oceans could be darkened by sediment in the water, or the lighter water could transmit the darkness from the deep. The blue of the oceans could reflect against the particles in the sky and create a canopy of blue. That is also probably incorrect. The different concentration of particles in the sky would create an uneven canopy of blue, with other colors poking through. Also, without like to broadcast the ocean's blue, the 
 
Many tropical plant fossils have been found in Antarctica, which is definitely not a tropical place. There is a widely accepted theory that explains all of this: plate tectonics. Plate tectonics is the theory that the earth's crust is made up of tectonic plates. These plates "float" on the mantle, which moves due to convection currents. The plates each contain a different amount of ocean and land. When the plates move, it drastically changes the landscape. Many years ago, the plate that contains Antarctica was in a very different place.

Pangaea was the second known supercontinent on the face of the Earth. During the time of Pangaea, all of the land was a central mass surrounded by a global ocean. This mass was near the equator and had many tropical regions. When the movement of the plates broke up Pangaea, the bits of land took their fossils with them. Some of the fossils were tropical ones, and some of the plates went to very nontropical regions. This led to scientists theorizing that some landmasses were once in different places.

Other pieces of evidence helped with that theory, too. The fossils of numerous non-aquatic dinosaurs were found around the coasts South America and Africa. This also suggests that the continents were once joined. There are also broken up rock deposits and glacier paths that can be connected to re-piece the continents.
 
The blue duiker is a very important animal in Africa. It is used as food for many people and is also used in making traditional karosses. There is even a myth that ends with Tortoise turning Duiker's horns into a musical instrument. Because the blue duiker is so important, many people have hunted it, to a point where the population was in danger. Fortunately, the population is now strong, except in areas with a large amount of human activity. However, there is still concern about the blue duiker, and so it is on Article II of CITES, which means that any international import or export of blue duikers should be extensively monitored, but is classified as Least Concern (LC) on the Red List. 

Because blue duikers are favored in many parts of Africa, husbandry, or breeding of the animals, has been attempted. It has not continued very far, but blue duikers of the fourth generation of human raising are nearly as domestic as goats, if nurtured by humans. Blue duikers are in many safari grounds, but otherwise are not much of a show/circus type of animal. There are some in captivity, however, they sometimes develop rumen hypomotility syndrome, or RHS. This is where lack of mobility causes a fatal build-up of the rumen. Blue duikers are very interesting and important animals, and are currently housed at the Fresno Chaffee Zoo.


Continental Drift

3/24/2013 09:46:45

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Many fossils from the past are found in completely different environments. This can be explained by tectonic plate movement or continental drift. The Earth is made up of tectonic plates that float on the semi-liquid magma below. The plates are moving very slowly, but over millions of years, made changes have occurred. Earth used to be a single humongous landmass, known as Pangaea. The fossils were most likely formed around Pangaea's time.

Pangaea was made up of different tectonic plates, and as they drifted away from each other, Pangaea broke up. Eventually, the plates settled in their present homes, although they still carried the remains of organisms from their home. The current Antarctic plate no doubt used to be in South Pangaea. The tectonic plates are still moving, however, and eventually Pangaea will reform on the opposite side of the Earth.
 
Throughout the course of the year, my science class has made a series of Quizlet sets, one for each new topic. These sets help us remember the terms through us typing in the definitions, and we have an easily accessible study guide with many different options. The options include Scatter, where terms and definitions must be matched; Space Race, where definitions can be eliminated by having their term typed before they reach the edge of the page; Speller, which is an audio fueled spelling test; Learn, like Space Race but not in a game mode; and Test, where Quizlet generates a test using a few of your own terms.

These options have helped me study for many tests, and I think that Quizlet is a very useful tool. I do not have an alternate study tool to suggest over Quizlet and recommend that its use is continued.