Meiosis

Meiosis is the process of cell division where sex cells are produced, also when chromosomes split and form sex cells in the end. The male sex cell is called sperm and the female sex cell is called an egg. This division occurs in all eukaryotes. There are three basic steps:
1) the chromosome doubles
2) the 1st division
3) the 2nd division

Here’s an example of meiosis. A human body cell has 46 chromosomes. Female:

46

I

92

/ \

46 46

/ \ / \

23 23 23 23

I \ I /

1 egg & 3 polar bodies

or

\ I I /

4 sperm

Interesting facts that I learned were:

1) There are four stages in a nuclear division: prophase, metaphase, anaphase, and telophase.
2) Meiosis comes from the Greek work meioun, which means “to make smaller.”
3) Some eukaryotes lost the ability to carry out meiosis and got the ability to reproduce by parthenogensis.

In my opinion, I think that meiosis is an important part of life. Without the process of meiosis, any living organism wouldn't be able to reproduce. If our parents didn't reproduce, we all wouldn't be here today.

Here are the links to the articles I got my information from:

http://www.accessexcellence.org/RC/VL/GG/meiosis.html

http://en.wikipedia.org/wiki/Meiosis

Cells

Cells. Such a tiny word can mean so much. A cell is the basic unit of life. Every single living organism has cells. Cells are everywhere, because they are microscopic. There are unicellular and multicellular organisms. Organisms that are unicellular, for example, are bacteria, yeasts, and amoebas. Other multicellular organisms are plants, animals, and humans.

Interesting facts that I learned from these articles are:

1) It takes millions of cells to make up the skin on the palm of your hand.

2) Animals have a skeleton because of a unique structure, the cell wall, which is why plants droop.

3) The human body has over ten trillion cells. (10,000,000,000,000)

In my opinion, I think that cells are the most important subject in science and life. Every living organism has cells, which I think, is extremely interesting. There would be no life if there weren’t any cells. Cells make everything come to life because it is the basic unit of life. If it weren’t for cells, we wouldn’t have most of the supplies we need today.

Here are the links to the article:

http://www.worldbookonline.com/wb/Article?id=ar102240&st=cell
username: xroads
password: vikings

http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htm

Europe's first stegosaurus was discovered.

What dinosaur do you know of that is an herbivore, 20 feet long and is studded with spikes on its tail? If you guessed a stegosaurus, you are correct. After the Jurassic period ended, about 150 million years ago, all dinosaurs became extinct. Because of this, there are fossils from these dinosaurs. Europe found their first stegosaurus fossil. Dinosaur fossils are usually found in North America, but not commonly in other continents. Surprisingly this happened. When the continents were still connected, Pangaea, dinosaurs would cross land bridges to other parts of land, which in this case is now known as Europe.

I think that this extremely fascinating to find fossils in other continents. Before reading this article, I thought that dinosaurs fossils were only found in North America and not in other coninents.

Finding dinosaur fossils can relate to science because when you discover something new you want to research about it and know more about it. By resarching about the fossil it can tell you what kind of dinosaur it cane from and learn more about that dinosaur. This can also relate to life because dinosaurs were once living, just like humans, but then became extinct.

This article can be found at cnn.com. Here's the link
http://www.msnbc.msn.com/id/16926228/

An astronomer without a telescope?

Can you find a planet or star without using a telescope? The answer surprisingly, is yes. Many astronomers do not use a telescope but use a computer. Amateur astronomer, William Bianco, searches for new stars and planets on his computer. Bianco is a political science professor at Indiana University. He isn't the only scientist that uses the computer, but other professional astronomers also prefer the computer over the telescope. Scientists choose the internet than the telescope because they often fight for telescope usage at major research observatories. Also, the information on the internet is up to date and you are able to access more data to help research. One of the first softwares that was used for astronomy was the SETI. The software sorted through information that measures tiny gravitational movements in a star's motions in search of planets that orbit stars other than our sun. Virtual astronomy didn't become popular until the late 1990's.

In my opinion, I would say that professional and amateur astronomers help each other to study the outer space. Researchers post their data and discoveries online and this allows others to use the information to continue their research.

This can relate to science and life because astronomers reasearch the outer space so others can understand it better and they also search for life on other planets.

This article can be found at cnn.com. http://www.cnn.com/2007/TECH/space/01/15/virtual.astronomy.ap/index.html

How did he die?

A 22 foot long whale shark mysteriously died last Thursday at the Georgia Aquarium in Atlanta, Georgia. On Friday, scientists were trying to conclude how the whale shark died. Ralph, the whale shark, was 22 feet long and weighed between 1700 to 2500 pounds. The staff at the aquarium noticed Ralph had stopped swimming and sank to the bottom of his tank. Now, they knew that something was wrong. Ralph died later that evening on Thursday, January 11, 2007 at 9:30 P.M. The aquarium workers still don't know the cause of the death. In November 2006, Ralph had a physical exam that showed he had an unusual swimming behavior and his appetite was on and off.

I hypothesize that Ralph died from a type of cancer or illness because the physical exam stated that he had unusual swimming behavior and his appetite was on and off. If you were sick, you may not feel like doing normal everyday activities. For example, if you had an illness it could keep you from walking. That may be why Ralph had stopped swimming.

This article can relate to science and life because it is about nature and how animals can die from unknown causes, just like humans. For instance, you could be healthy and have a heart attack the next day. The heart attack could have suddenly occured and killed you.

I found this article at cnn.com. Here is the link to the article http://www.cnn.com/2007/TECH/science/01/11/aquarium.death/index.html

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