do the chloroplasts move in same direction, at same speed in an elodea cell? do the onion cells have depth?

Question

in elodea cell tell me the location of nucleus cell.
can u observe any structures for movement? (i dont understand this question) plz answer this.
onion cell: tell me location of nucleus, color of cytoplasm
what happens if u add iodine, tell me about depth how can u determine that the onion cells have depth or not? explain
plz answer these questions.

thank u both, for your answers.
actually i didnt understand what did we have to do and also some questions that were part of the lab 9 didnt make sense) it was the last day before christmas break .

i mean that how many cell layers thick is the onion tissue?

Answer 1

Did you miss this lab, or did you not understand what you were seeing? If you don't understand while you are in the lab, be sure to get help from your lab partners or from your teacher. You will remember so much better if you understand the material on the spot - while you are doing the work.

The next best thing is to view pictures of the results. Here are some sites to help you with what you need to know.

1. See the cytoplasmic streaming in an elodea cell to see if the chloroplasts are moving in the same direction and at the same speed. http://www.altavista.com/video/results?itag=ody&q=streaming+elodea&kgs=1&kls=0 Click on any of the choices.
2. Location of nucleus in elodea cell. http://www.uq.edu.au/_School_Science_Lessons/3.23.10.GIF
3. Do you observe structures for movement in elodea? Did you see any cilia or flagella? The answer is "no".
4. Onion epidermis cell. Without stain the cells look pretty much like this. The cytoplasm is colorless and the other parts don't show up much either. I suspect that this sample is actually faintly stained, but you can get the idea. http://web.grcc.edu/biosci/pictdata/bi103/whiteon.jpg

Adding iodine stains the nucleus and cytoplasm to look like this: http://science.tjc.edu/Course/BIOLOGY/1408/onion_epidermis.jpg The nucleus of each cell is the small round part that has one or more little circles inside. It looks a bit like a fried egg. You can see its location in these cells.

You can tell if cells have depth by turning the fine adjustment knob of the microscope up and down slightly while you watch through the eyepiece. You should be able to see different parts of the cell as you focus up and down.

Answer 2

Chloroplast Streaming

Answer 3

I don't remember where the nuclei are in elodea cells, but the chloroplasts don't move in the same direction or at the same speed. I don't understand the question about movement of structures, but I assume you could, considering that everything in a cell would probably have some kind of movement.

In onion cells, I remember the skin cells' cytoplasm was clear. The nuclei are in the center (I'm pretty sure), and if you add iodine, the nuclei turn orange/red. I don't understand your question about depth.

I hope that helped a little. I only know the stuff that we covered in biology labs, so I don't know the answers to some of the questions.