At first we discussed our answers for pg.97 in the textbook. This we did in our groups. Mr. Finley gave us until 12:30. Then after that Mr. Finely dicussed what we leard the last couple of days.He could not walk around the all the different groups,because he was teaching his own lesson. We had a discussion of what happens in prophase. The main thing that happens during prophase, is that the nucleus breaks down. Mr. Finley reminded us that there are alot of similar words, for example some are, Chromozone chromatid,chromotin. when a student got confused.

The three main things that happen during prophase is the chromatin turn into chromezones, the nucleus breaks down, and the centrosome become two centreolles and move to opposite parts of the cell. Each centreolle split the chromozone by shooting spindle fibers at the chromozone and pull it apart.When cells messd up in mitosis( this happens rarly) people can get cancer or toumers.

During Telaphase a new nucleus comes back, also chromozones turn back into chromatin. Then the cell membrane starts to strech. the starting of splitting happens in the very end of Telophase. The actual splitting happens during cytokenisis. Y.S

staions

Today we are continuing our stations. My group is at the station where we are looking at an onion root tip on a micriscope on the smartbored. Mr. Finley is talking about a cell reproducing. He is pionting to a cell to point iut the cell wall forming. Now he is showing us a cell that is starting in anaphase. When an amnimal cell divides it pinches and then split apart.
Now we are at a new station where we are on the computers on a website and taking notes. I am drawing a picture of the cell on the website.
Notes:
interphase: cells may appear inactive during this stage but they are quite the opposite. Its the longest period during which the DNA replicates.
Prophase:
During this stage the nucleus fades and cromatin condences into cromosomes.
BB

3/8/11 stations

Today we started class by taking out our lab sheets from yesterday. Mr. finley said then that we were going to be doing station work today. Our group first had to do station 1 which was completing questions in the textbook on page 97. Another group was at the smartboard with Mr. Finley, and the last group was online at cellsalive.com on the mitosis site. At station 1 the group went over some qustions about mitosis based on a graph with the amount of time the cell spends in each section. Some of the questions were like how long is the cell in interphase and how long is mitosis. Our group got done with all the multiple choice questions and then got to some open-ended ones about how to set up an experiment to test for mitosis while changing a ariable. We said that you could do one plant under high power light and another under low and a final one with no light.At the smart board with Mr. Finley we said that in the onion root cell we will see mitosis because the roots need to get water for the onion. We also said that the died parts in the cell are chromosomes that are seperating and that different cells can be in different stages but one cell can be inbetween two different stages. We said that in anaphase spindle fibers pull apart the chromosomes to make a new cell. We did not get to station 3 so check Tomorrows blog to see what happens on cells alive.com in stage 3.
I(n the picture above chromosomes are being seperated to make a new cell.

PH

Cell Division Date 3/ 7/ 11

Today we began the class by working on our cell division worksheet with the onion ring. We are using microscopes in order to answer the questions on this worksheet. Mr. Finley reminded us that the onions we are using are not necessarily going through metaphase. Then, one of our classmates asked a very good question which was, "When we looked at grass cells and onion cells before, why didnt we expect to see mitosis?" Then Mr. Finley explained to us that we are now looking at the root of the onion. And we expect to see mitosis now because the root collects nutrients and water for the onion in order for the onion to grow and develope. This is why we expect to see it go through mitosis. Under low power of the microscope we saw one big circle that had hundereds of other really light circles. Inside each of the little circles we saw a darker circle in the middle and in the middle of that we saw a black dot. When we switched it to high power we saw in greater detail, the lighter circles. And we believed that those were the cell membranes of the cells. Inside that we saw a darker brownish circle that we believed was the nucleus of the cell. Lastly, in the center of that we saw a smaller black circle. And we believe that the black dot could potentially be the DNA (deoxyribo nuclaic acid). Our group also something quite peculiar. We saw that we saw a cell had two black circles and we believed that it was quite interesting. Our group had found several stages in our onion. We found anaphase, telephase, interphase, and prophase. We noticed that some cells were bigger than others. Which are signs of mitosis occuring.

Today was a great day because it really got my group and I thinking and understanding the stages of cell division.

BY,
LB

Today, we started out by talking about chosing group leaders. One person a day in each table has to be the leader of the group meaning that they must keep their table group on task. The 3 responsibilities of the leader are:
1) Make sure everyone is engaged and everyone is participating in the discussions.
2)Make sure everyone is on task (members of the group are not wandering around the room, talking about non-science realted topics, making sure that if the group gets off topic that they get back on topic as quickly as possible)
3) Make sure things get done on time.
If the requirements are not met, the leader will lose their 5 participation points.

Next, we continued going over the questions that we did on 78 and 85 in the science book on March 1st.
4) Q:How does DNA compact before a eukaryotic cell divides?
A:The DNA is wrapped up around proteins in chromosomes.
5) Q:Why do injuries to the skin generally heal faster than injuries to the brain?
A:Because the skin cells have a shorter life cycle. It has more layers underneath that are available in case you lose cells when you get hurt and need more right away.
7)Q: What are the 2 main parts of the cell cycle?
A:The 2 main parts are interphase and mitosis.
9) Describe the steps of mitosis.
1) Prophase- chromosomes condense
2) Metaphase
3) Anaphase- chromosomes seperate
4) Telophase- 2 nucli are formed

Then, we started our lab. For our lab, we are using microscopes to look for tips of onion roots and then we answered questions on the worksheet we got.

vp-3

We are doing some questions in class today.

1. What is an example of a one celled eukaryotic organism?
2. One example is paramicium.
3. What is an example of a multi celled organism?
4. one example is a human.
5. which example above would use mitosis to grow/develop/repair cells? Why?
6. The multi celluar organism needs to grow, so that means humans use mitosis and a paramicium does not.
7. How would the other use mitosis?
8. The other cell does not use any mitosis.
9. What would be true about the 2 resulting cells?
10. Both cells would use the same DNA.
11. Is this true about any 2 cells we compare in a multicelluar organism?
12. Yes, because all eukaryotic multi celled organisms perform mitosis.

CELL REPRODUCTION IS MITOSIS!!

First Mr. Finley checked our homework. So you know since everybody in the class completed both assignments so if you were either absent or not paying attention you got 2 extra credit points. The term for cell reproduction is mitosis, or you may hear cell division. The 5 stages of mitosis are Interphase, then Prophase, Metaphase, Anaphase, and finally telophase. How to tell which fase a cell is in...you would have to look at the arrangement of chromosomes.

In mitosis, for a new cell to be made, a cell has to split in half. In order to split in half it needs new DNA for the new cell. This is how new cells are made. DNA is in its spegetti like strand and then it gets copied or replicated. Then there is new DNA for the new cell.To bond the two DNA strands there is something called a kineticore. Only Eukariotic cells may do this. Prokaryotic cannot do this because they do not have a nucleus. If you don't have a nucleus you can't make chromosomes. Whats the reason we need new cells some on asked? You need new cells because if you get a cut in your skin, you need more cells to to fill the cut. Also you would need more cells because since you grow, you would need more cells to to get bigger. You would have more skin, which would need more skin cells. That is just one example, but there are many. Everything is ready before mitosis occurrs such as proteins, new DNA, and chromosomes. Interphase is like your everyday for a cell except that one day where you do things differently like a holiday. This holiday is just metaphore for mitosis.


Jordan Price