Mitosis Write-Up

Mitosis (onion roots) Root cells be good for observing mitosis this is because theyre in the tip of the root which is an bea of the establish that grows quickly. This results in more cells going through mitosis all at once, likewise allowing us to examine the different symbolizes of mitosis. Stages1. Interphase deoxyribonucleic acid replicates, but has not organize the condensed structure. They remain as loosely coiled chromatin. The nucleus is still intact.2. Prophase The DNA molecules progressively shorten and condense by coiling, to form chromo roughs. The spindle fibres ar pulled to opposite sides/poles of the cell.3. Metaphase The spindle fibres attach themselves to the centromeres of the chromosomes.4. Anaphase The spindle fibres shorten and the centromere splits, disordered sister chromatids are pulled along behind the centromeres.5. Telophase The chromosomes reach the poles of their respective spindles. thermonuclear envelope reform before the chromosomes uncoil. Th e spindle fibres disintegrate.Method/Procedure1. mooring some premixed 1 molar Hydrochloric acid and Acetic Orcein in the watch glass. uniform essay Why Would We Choose An Embryonic MassBe careful not to bemuse this mixture on your skin or clothing. * Hydrochloric acid (HCL) breaks down the affection lamella and softens the cells tissue and the cell will lose its 3-D shape.2. In to this mixture place the terminal (end) 3 or 4 mm of a garlic root (remove the rest of the root). * The cut end inescapably to be removed in order to avoid haphazard delusions.3. Place on the 40oC heating blocks to warm. In a short time (a few minutes) the root tip will feel soft when touched with a mounted needle (Do not let it dry out completely). heating system it in order to speed up the process of the cell mole breaking down, and also for the dirty word to spread quicker. The stain will confiscate with the DNA, and it will become more visible.4. Now, using forceps or the mounted needle, cle an up the softened root tip and transfer it in to a clean slide.5. Add a few drops of Acetic Orcein6. Using a mounted needle macerate (Squash) the root tip.7. Once this procedure is complete, carry out a clean coer slip to the slide and heat it quietly on the 40oC heating blocks for 10 seconds to intensify the stain.This will spread the stain and allow it to bind with the DNA.8. Then invert the slide on a blotting paper and push down ward firmly, applying pressure with your thumb over the cover glass. This should flatten the cells and disperse them so they can be find under the microscope.This will help flatten it to cell thick.Depending upon how effective your grind has been you may either use this or a pre-prepared slide to surveil the stages of mitosis in the root tip you will use either wizard to identify and record the different stages of mitosis.Variables Independent Variables The slide itself, however, we dont know anything about the slide.Dependent Variable The percent age of cells in each stage of mitosis. Controlled Variables No. of cells counted. The magnification power used. Were my results valid and veritable? Valid To crack my results were valid, I compared my results with the other classes results, who were also undertaking the same experiment. Also, I compared them to other results Ive have online, and made sure they both agree. Reliability My results were reliable because, 20 other different students in my class also did the experiment, and my results are the average of them all.Errors I have identified some systematical errors, such as students consistently looking at the wrong section of the root, as conflicting to the growing section. We do not want this as it will upon our resultsHowever, if one individual does this then it will become a random error along with students confusing stages together. e. g. If you look at the attached info student TW overestimated the telophase cells, and underestimated the prophase cells. This is a p rime instance of a random error in my results. Trends and patterns I have identified several trends and patterns in my results, for example the interphase stage took the longest.I expected this to be the case because interphase has along of stage within itself, so it is understandable for it to take considerable more time than the rest. Also, I have noticed that anaphase took the shortest amount of time, as it is just the centromeres splitting and separating. passage of Mitosis If a group of cells is dividing rapidly, a high proportion of the cells will be undergoing mitosis. A group of cells that is not dividing will have all cells in interphase of the cell cycle. The amount of cell division occurring in a tissue can be quantified using the mitotic major power.The mitotic index is used for studying tumor growth in cancer patients. Using the formula below, calculate the mitotic index for your root tip preparation. If you have time, compare this value with the mitotic index of a n field of operation of cells away from the root tip and comment on your findings. e. g. Mitotic Index = spell of cells containing visible chromosomes total number of cells in the field of view selective information analysis DIV/0 = Mean. // DIV0 Of the phases 13. 126315. Precision To the nearest cell (1dp) Title % of time spent in each phase cycle.