Onion Root Tips Mitosis WebQuest

ONION ROOT TIPS AND THE CELL CYCLE


In this activity, you will calculate the lengths of the various phases of the cell cycle in an onion root tip. First you will view some slides and graphics of onion root tips provided by the Molecular Expressions Photo Gallery. Then you will complete the online activity provided by the Biology Project at the University of Arizona.

Part 1.

Use your browser to go to Molecular Expressions Photo Gallery: Mitosis

http://www.microscopy.fsu.edu/micro/gallery/mitosis/mitosis.html

Notice in the micrograph at the top of the page that there are cells in a variety of stages. View the onion slides in this section, then click on "mitosis" in the sentence "Learn the steps in mitosis ... " This will take you to a Java tutorial.  Keep in mind what you have learned here as you proceed to the second part of the activity.

Part 2.

Use your browser to go to Online Onion Root Tips at

http://www.biology.arizona.edu/cell_bio/activities/cell_cycle/assignment.html
Begin by reading the description of the five major cell phases. You will need to keep this information in mind during the activity.

Make a copy of the data sheet that appears on the second page. You will need it to answer the questions.

Proceed through the activity, identifying the phase for each cell you are shown. Pay attention to the hints if you misidentify a cell at first.

When you have completed the activity, answer the following questions:

1. What percent of cells were in interphase?
20%2. What percent were in mitosis?
100% All of the cells are in different stages of mitosis.3. Which phase of mitosis takes the longest?
Interphase
4. During which stage is the nucleolus visible as a dark spot?
Prophase5. How can you recognize a cell in metaphase?
It doesn't seem as dark as prophase; It's much lighter and looks like it's beginning to separate.6. How might you figure out how long (in minutes and/or seconds) each phase of the cell cycle takes based on the data from these onion root cells? Explain your logic and show your calculations and results below.

7. Produce a pie chart in Create-a-Graph that shows the relative lengths of each stage of the cell cycle in these cells including interphase and each stage of mitosis. You can embed the graph here.

	Interphase	Prophase	Metaphase	Anaphase	Telophase
Number of Cells	20	10	3	2	1	36
Percentage	55.55%	28%	8.33%	5.56%	2.78%	100%

Cancer Cells

Cells go through a cycle which includes many processes. These are:
1. Interphase
2. Prophase
3. Metaphase
4. Anaphase
5. Telophase

How do cancers...happen??
When cancers develop, it is because proteins don't work the same way because cells don't go from one stage to the next properly in their cycle. The cancer cells reproduce at a far faster rate than normal cells do. But those cells all seem to have a loss of function. This happens because the cell division does not happen properly. In most cases, cancer takes many years to develop.

So...give an example of a cancer and how it happens...
Let's use breast cancer as an example!
So breast cancer is a type of cancer that will form in any part of the breast. It's more commonly seen in women, but men are also at risk of getting this cancer, too. When cancer begins to occur, cells begin to go through a change which rapidly spreads through the body (as previously stated). Women release a hormone, estrogen, which stimulates cell division, but may effect cells and DNA to be damaged or permanently effected. Women who have not been through a first term of pregnancy still have immature cells and can be more easily effected by this because their cells contain carcinogens that are not as strong or able to repair damaged cells as easily.

How can one treat this?
Through cell technology and radiation techniques, scientists have found new ways to practically zap away the bad! Treatment programs can be created to help the side effects of the cancer be reduces and can even eliminate the cancer altogether!

Sources:
Scitable by Nature Education

The Biology of Breast Cancer

Breast Cancer

As it is the new year, I would like to present to you this month's end-of blog-picture topic! The snake! Happy 2013, the year of the snake!

What You'll Wish You'd Known Response

What You'll Wish You'd Known

     In the article, What You'll Wish You'd Known, I read about how the average graduation speech about "never giving up" and "following your dreams"...is all misleading and wrong. I definitely agree with this speech because things are always different in high school than they are in the real world. When we are in high school, we are still fairly new to the world, and learning exactly where our place is. If we follow the dreams that we have while we don't really know ourselves, we're bound to end up somewhere later on that we don't want to be. However, if we do what the article tells us to do and just keep pushing on, believing that we're gonna make it, then we're more fit to get somewhere good. I can see how this speech was denied for graduation, however. At this time in our lives, we've all figured out that the tooth fairy, Santa Claus, and even the Easter bunny are all- yes- fake. But we still believe in some kind of magic. A magic of hope, dreams, and never giving up. We're still children, in this sense. But if we hold on to something forever, we're bound to have so many corpses of dreams that it could potentially lead down a path to self destruction. So basically, we must go with the flow and keep fighting!