Mitotic Stages Essay

     The leptotene. This phase differs only slightly from the early stages of mitosis. Usually are the cells and nuclei of meiotic tissues bigger than that of their neighbouring tissues and often do they seem to be longer and are longitudinally structured. At regular intervals can thickenings be found, like beads on a string: the chromomeres. Their number, size and positioning is constant in each species.

Exercise 3A is a study of mitosis. You will simulate the stages of mitosis by using chromosome models.You will use prepared slides of onion root tips to study plant mitosis and to calculate the relative duration of the phases of mitosis in the meristem of root tissue. Prepared slides of the whitefish blastula will be used to study mitosis in animal cells and to compare animal mitosis and plant mitosis.

In this experiment first the stages of an onion cell undergoing mitosis are going to be observed and every stage is going to be detected and drawn on paper. A brief description to what is going on should be attached to the pictures. This is important to understand the basics of cell division which is necessary growth,repair and asexual reproduction. Second the number of cells undergoing each phase is going to be counted to figure out in which phase the cell remains the most. If interphase is the stage in which the cell grows and prepares for cell division then the

According to Mattias Schleiden and Theodor Schwann the cell is the basic unit of life(Cell Theory- OI). Two common types of cells are the plant and animal cells. Although both kinds of cells share many similar, abundant structures, they also have varying descrepancies from cell to cell. Without a doubt, the nucleus is the most important organelle in the plant cell, even though, the lysosome is the most important structure in the animal cell.

In the onion root tip, regions other than the apical (or at top of) meristem contain cells that are not actively dividing. These cells are in interphase. In this case, they would represent the majority because cells spend most of their time in interphase anyway. They are elongating, differentiating, and performing their functions for the organism. Mitotic stages would not have been found in these areas.

Compare and Contrast Mitosis and Meiosis Meiosis and mitosis describes the process by which cells divide, either by asexual or sexual reproduction to produce a new organism. Meiosis is a form of cell division that produces gametes in humans these are egg cells and sperms, each with reduced or halved number of chromosomes. The number of chromosomes is restored when two gametes fuse together to form a zygote. A cell with two copies of each chromosome is called diploid cell and a cell with one copy of each chromosome is called a haploid cell.

1) Apply the stain to your first unknown slide and examine it under the microscope.

4. Identify the endocrine organ from which a slide is prepared when viewing the slide with a microscope.

Although mitosis is just a fraction of time compared to interphase it can be divided into four distinct subphases. If we start viewing a cell under a brightfield microscope right at the end of interphase subphase G2 we would see that throughout the interphase process (fig 1) the cell has grown considerably in size due to production of extra mitochondria and endoplasmic reticulum. The cell has also gone through the labor of duplicating all of its chromosomes, a process known as DNA synthesis. Now that the cell has made all of these preparations it's time to start prophase (fig 2), the first stage of the mitotic phase. This stage is visibly identified by the chromatin becoming the tightly formed chromosomes. During the lab we were able to view these newly formed chromosomes best on the onion root tip

3. Switch to high power and center your slide in the apical meristem region, so that you have a field of view in which there is a wide selection of cells in various stages of mitosis (including interphase). Be sure to adjust your light for optimum viewing. Refer to Figure 3A, 3B, 3C: Stages of mitosis in onion root tip cells for guidance.

18) Looking into your microscope, you spot an unusual cell. Instead of the typical rounded cell shape, the cell has a very narrow middle separating two bulging ends. It sort of looks like the number 8! Then you realize that this cell is

cell will look just like any other 'normal' cell although this is far from the

angle value of 43.5 degrees on the incline plane (Fig 2). On the molecular level, staining

Making the onion tip root cell slide was successful. Our results supported the hypothesis because we saw cells in the onion root tip in prophase, metaphase, and anaphase. As we went up in power objectives, each phase of the cell became more definitive. The cell root was a great indicator of the structures of the different cycles of the cell. This is important because we will be prepared for future labs working with the microscopes and can now adjust it for the best view of the slide. We practiced working with the compound light microscopes and different phases of the cell cycle. Onion root tips are useful to observe mitosis because the cells are frequently diving as the root grows. So when we stained the cell, we caught many cells in different phases. The significance of this lab was to better understand the process and stages of mitosis and meiosis and compare and contrast the mitotic process in plants and animals. We grasped the concepts of what the chromosomes look like, and what they look like in each step of the processes. Having read much about mitosis and meiosis, seeing these cells was the real application of describing and understanding the stages.

I predicted that the unknown is a human cell because it has a rounder structure. Even Though the shape of the cell rigid and keeps it in a specific shape. it is more likely to be a animal cell than plant cell because it doesn't have a cell wall. Since there’s two different examples of plant cells than there has to be two examples of animal