11/19/10 P8

Today, we finished off the grass lab and started the onion lab. For the grass lab, we got some grass from outside and we put it on the slide, and then we put one drop of water on it. Then we put the cover slip on it and looked at it through the microscope. The cells were green and quite opaque, are light can't go through it much. The cells were also circular. It was also harder to see the parts.

For the onion lab, we took a paper thin piece of onion and put it on the slide. Then we put one drop of iodine and put the cover slip on it. Then we looked at it throught the microscope. The onion cells were more colorless. Also, ther were no chloroplasts in it. This is because the onion is under-ground. Since it is under-ground, the sun can't reach it, which means it can't do photosynthesis. If it can't do photosynthesis, there is no need for chloroplasts.

After we looked at the plants, we had to answer some questions. Here are the questions.

• What is a cell? Why are they considered building blocks?



• Why did our grass have to be very thin?



• Why didn't we see any chloroplasts in the onion?



• Make a table of the differences between a animal cell and a plant cell.

It is confusing to know that there are different kinds of cells. It is also hard to memorize it. But, once you start to learn more about it, you get the hang.

Here is a video on the inside of a cell. It is hard to understand in some cases, but it is visually helpful, and names most of the parts we learned about, although it goes into more detail and there are things we never learned about. Here's the link:

http://www.youtube.com/watch?v=dCHre3-_KjA&feature=related

By Rohan Mallya